Final Report Summary - HELCATS (Heliospheric Cataloguing, Analysis and Techniques Service)
Executive Summary:
The advent of wide-angle imaging of the inner heliosphere has revolutionised the study of the solar wind and, in particular, transient solar wind structures such as Coronal Mass Ejections (CMEs) and Co-rotating Interaction Regions (CIRs). CMEs comprise enormous plasma and magnetic field structures that are ejected from the Sun and propagate at what can be immense speeds through interplanetary space, whilst CIRs are characterised by extensive swathes of compressed plasma/magnetic field that form along flow discontinuities of solar origin that permeate the inner heliosphere. With Heliospheric Imaging (HI) came the unique ability to track the evolution of these features as they propagate through the inner heliosphere. Prior to the development of wide-angle imaging of the inner heliosphere, signatures of such solar wind transients could only be observed within a few solar radii of the Sun, and in the vicinity of a few near-Earth and interplanetary in-situ probes. HI has, for the first time, filled that vast and crucial observational gap. Recognising that a number of lines of research have addressed the deceleration and deflection of CMEs and interaction between CMEs and between CMEs and CIRs, and that considerable evolution of a CME can be witnessed in the HI images during its passage through the heliosphere, exploiting the HI images in studying the propagation of CMEs through the heliosphere must become an essential element of future space weather application; it is not acceptable to simply rely on knowledge of the passage of a CME through the corona and await its arrival at 1 AU.
The HELCATS project provides an unprecedented focus for world-leading European expertise in the novel and revolutionary, European-led field of HI, in terms of instrumentation, data analysis, modelling and science. HELCATS is a strategic project that empowers the wider scientific community, in Europe and beyond, by providing access to advanced catalogues - validated and augmented through the use of techniques and models - for the analysis of solar wind transients, based on observations from European-led space instrumentation. All of the beneficiaries are at the forefront of heliospheric research and bring distinct, yet highly complementary, skills to the project. HELCATS adds significant value to the exploitation of existing European space instrumentation, providing a strong foundation for enhanced exploitation and advancement of European heliospheric research.
HELCATS recognises the synergy between solar and heliospheric physics research (both of which are European strengths) and their applied space weather aspect, currently a topic of vigorous debate in many political and scientific arenas. With the current development of a European space weather capability, within ESA’s Space Situational Awareness programme, HELCATS has real, practical relevance. Certainly the HI concept is high on the priority lists for the payloads of missions that are being defined at this time, and the exploitation of those instruments, for the detection and analysis of potentially Earth-impacting events, will be significantly enhanced by the outcome of the HELCATS project studies, in defining methods and models for adoption.
The HELCATS consortium is led by STFC’s Rutherford Appleton Laboratory. The Coordinator is Professor Richard A Harrison, the Scientific Manager is Dr Jackie A Davies, and the Technical Manager is Dr Chris Perry. The fundamental aim of the HELCATS project is to start with heliospheric imaging observations and, from that, build up facilities, methods and assessment studies in a logical programme of activities. The work is managed by STFC, involving a total of eight European research groups, or beneficiaries. The activities of the beneficiaries are tailored to their scientific and technical strengths, maximizing the potential scientific return for the project.
The list of beneficiaries includes the Science and Technology Facilities Council (STFC), United Kingdom, the University of Graz (UNIGRAZ), Austria, the University of Paul Sabatier (UPS), France, the University of Goettingen, (UGOE), Germany, the Royal Observatory Belgium (ROB), Belgium, Imperial College London (IMPERIAL), United Kingdom, University of Helsinki (UH), Finland and Trinity College Dublin (TCD), Ireland. Key to the success of HELCATS has been the combination of space-hardware, observations, data, theory, modelling, across a critical range of solar and heliospheric disciplines, that the beneficiary group provides. In addition, the HELCATS project includes two third parties, not shown in the table; this includes George Mason University (USA), to enable close modelling ties between UPS and the developer of the Enlil model that is used extensively in some aspects of the project. The second is CNRS, which is the employer of the key staff at UPS; CNRS is included as a formal third party for managerial reasons rather than direct input to the project.
Project Context and Objectives:
The concept for this project comes out of the recognition that there is potential for adding considerable value - for scientific exploitation and space weather studies alike - by pooling the considerable and world-leading European expertise in this field (in terms of science, instrumentation, modelling, etc). A programme of cataloguing, modelling validation and information provision would clearly bolster community-wide research into the physics of the heliosphere – the volume of space in which we live. Our aim is to enhance considerably the European lead in this key area of science research by applying a coordinated approach to the provision of techniques, tools, and data access. This goes beyond providing post-launch support for the STEREO instruments alone and beyond the individual research interests of groups around Europe.
The following headline activities form the basic set of objectives for the HELCATS project. The relevant Work Packages (WPs), tasks and deliverables are listed below. We note the relevant WPs here:
• Production of the first comprehensive catalogue of CMEs in the heliosphere for the period from 2007, using manual recognition of CMEs in STEREO/HI data but also assessing the potential for automatic CME recognition. (WP2).
• The generation (and inclusion in the catalogue), for those CMEs, of parameters such as radial speed, 3-dimensional (3-D) trajectory, orientation, projected launch time, and projected arrival times at various locations in the heliosphere, in particular Earth and other planets. This would be achieved through the application of a range of models (geometric and forward). The net result of these activities would be the provision of a unique and comprehensive facility for characterising transient activity in the heliosphere and, in particular, Earth-impacting CMEs. (WP3).
• Production of the first comprehensive catalogue of CIRs, including their modelled kinematic and spatial properties, from STEREO/HI data using manual recognition (over the same period). (WP5).
• Comparison with solar ‘source’ and in-situ data in order to correlate the white-light imagery with activity on the Sun and at various locations in the heliosphere (such as Earth and other planets), thereby providing validation of the models. (WP4, WP5).
• The application of global numerical modelling, that also allows an assessment of the potential for driving such models (widely used for space weather applications) based on HI data. (WP6).
• The assessment of the potential for combining white-light imaging of the inner heliosphere with ground- and space-based radio data, in particular Interplanetary Scintillation (IPS) and Type II radio bursts; catalogues of such radio events will be produced as required. (WP7).
• The dissemination of the aforementioned results, not only through publications emanating from the consortium but also from members of the broader scientific community through providing them with easy access to the catalogues/methodologies; the latter will enable a much wider exploitation and understanding of the HELCATS results. (WP8).
In terms of the practical application of the project, the work was managed through eight well-defined workpackages as listed below:
WP1: Management - The HELCATS consortium includes 8 European groups from 7 EU countries and two third parties. The project coordinates work involving observations, cataloguing, modelling, and studies in validation and assessment. WP1 covers the formal management roles of the HELCATS project. This includes administrative tasks, maintaining project infrastructure, coordinating inputs and reporting as required and handling a range of project issues. WP1 oversees the website production and management.
WP2: Producing a definitive catalogue of CMEs imaged by STEREO/HI - This WP provides the foundation for this project (including scientific coordination), namely the production of a catalogue of CMEs in the heliosphere. The catalogue is produced from manual inspection of STEREO/HI data but use of automated techniques has been investigated, allowing the manual and automated methods to be compared. Comparisons with coronal (coronagraph) CME catalogues have also been made, to compare the detection and analysis of CMEs in the corona with those detected in the solar wind.
WP3: Deriving/cataloguing the kinematic properties of STEREO/HI CMEs based on geometrical and forward modelling - Here we apply recently established geometrical, forward and (prototype) inverse modelling methods to derive CME parameters, which are added to the catalogue (including back- and forward-projections to ‘predict’ CME launch and arrivals at various Solar System locations). Comparisons have been made between the parameters yielded by the different models.
WP4: Verifying the kinematic properties of STEREO/HI CMEs against in-situ CME observations and coronal sources - This WP catalogues in-situ CME information (at Earth and elsewhere) for comparison to the projected data from WP3 in order to assess the performance of the aforementioned models. Similarly, comparisons are made with solar ‘surface’ phenomena. These allow a thorough validation of the models.
WP5: Producing a definitive catalogue of CIRs imaged by STEREO/HI that includes verified model-derived kinematic properties - In parallel with the CME cataloguing, modelling and model assessment in WP2-4, this WP performs an analogous activity for CIRs, again with cataloguing, geometrical modelling and the validation of results through comparisons to in-situ/solar data.
WP6: Initialising advanced numerical models based on the kinematic properties of STEREO/HI CMEs and CIRs - This WP recognises the potential for using HI data as input to numerical MHD models of the heliosphere (in terms of both CME and CIR phenomena) by considering the use of HI images for initialisation/driving of the ENLIL model. The results are compared to traditional methods for running such models, based on coronal and photospheric inputs, to assess their potential.
WP7: Assessing the complementary nature of radio measurements of solar wind transients - WP7 explores the value of incorporating radio observations, to augment the HI data. It assesses the value of using interplanetary scintillation (IPS) observations and Type II radio burst data in conjunction with HI data, both of which can provide additional information.
WP8: Dissemination - WP8 brings the results to the community through (1) the publication of results in the open, refereed literature, (2) the running of annual open meetings, (3) the installation of all relevant documentation, catalogues and reports on the website and (4) the dissemination of information to the public and policy makers. This includes ingestion of the products into the AMDA data-mining tool the IRAP (UPS) propagation tool, and integration with projects such as HELIO. This WP coordinates the exploitation of the project outputs, such that they feed into numerous research activities and future space weather applications.
Overall, the HELCATS strategy is to coordinate a range of observational and modelling studies of heliospheric phenomena to provide a foundation for enhancing the scientific discipline and the exploitation of European investment in the hardware involved. It is also a benchmark in the provision of facilities to understand the nature and development of solar transients in the heliosphere.
Full details of the HELCATS project can be seen in the description of work documents (606692_DOW_PART_A.pdf and 606692_DOW_PARTB.pdf) agreed with the European Commission in early 2014. Those documents also outline the resources per beneficiary, and by WP, in terms of finance and staff time. In terms of the productivity of HELCATS we do stress that the project was designed to provide a unique, timely facility for the research community, to drive a significantly better understanding of solar-generated transients and their passage through the heliosphere, as well as their sources and impacts. Thus, in keeping with the spirit of many EU projects, the aim is to provide the legacy of a thorough, global catalogue of heliospheric transients, that has previously not been available, and, in doing so, assess and validate a range of available models. The project is not a portal allowing use of a number of space-related data-bases; it is built on a specific instrumental and observational strength in heliospheric imaging, with the analysis and modelling activities that provide a global view of solar transients in the heliosphere that has not existed before. The project has added significant value to existing facilities and is clearly of direct interest to space weather applications in the near future. However, in providing the facilities (catalogues) and the assessment and exploitation of different models and methods, the project clearly provides a facility that is valuable to the wider research community and is not per se, a research project in itself. The basic aim was to deliver a legacy that can enable major scientific steps. Nevertheless, many of the results are published in the scientific literature and these are noted in the text and included in the publication list.
Project Results:
One of the international benchmarks for CME research is the CDAW (Coordinated Data Analysis Workshops) catalogue of events identified in the SOHO/LASCO coronagraph data (see https://cdaw.gsfc.nasa.gov/CME_list/). This facility has provided the gold standard in event identification and in enabling a wide range of investigations that have advanced the field of CME research considerably over the past 20 years. It does not replace the research; it enables the research by providing access to the event listings and the data, as well as basic analysis of the kinematics. The CDAW/LASCO event list is referenced directly in a large number of research papers. All of this relates to the passage of solar ejecta through the corona.
With the advent of the STEREO/HI instruments (Eyles et al., 2009), following on from the Coriolis/SMEI instrument, we are now observing CMEs in the heliosphere on a regular basis, well beyond the limits of LASCO’s field of view, and through interplanetary space to beyond 1 AU. The STEREO/HI instruments are led by RAL Space (STFC). Whilst recognising the value of heliospheric CME investigations to fundamental research, we also note the requirements of the space weather community, and these both stress the need for a similar benchmark facility for heliospheric CMEs. Hence, the concept behind HELCATS was born.
In many ways, the HI instrumentation and the HELCATS project work focus on the fact that prior to the advent of heliospheric imaging, CMEs could be observed in the corona but were then not detected until and unless they passed over spacecraft with in-situ instrumentation. As mentioned above, we recognise a 200 Rs ‘gap’ in observational capability that has now been closed. Tracking CMEs and studying their structure and evolution in the inner heliosphere enables studies of a wide range of issues such as CME onset and Earth arrival studies, CME-CME interaction, CME deceleration and deflection, the shock-CME relationship, and studies of other transients such as SIRs/CIRs. The value of such work for space weather impacts is clear, as is the opening of this vast new region for fundamental research into heliospheric physics. Thus, the value of HI observations is clearly of great importance for heliophysics research as well as space weather interests.
The HELCATS project work-plan outlined a set of clear elements and results, defined very much through the unique set of catalogues that have been subsequently developed, as detailed in the bullets, below. All of the catalogues mentioned are accessible through the HELCATS website, using the PRODUCTS tab. We group the catalogues for clarity:
(i) Heliospheric Imaging of CMEs (HICAT, HIGeoCAT and CACTusCAT)
• HICAT – The first definitive catalogue of CMEs in the heliosphere from outside the Sun-Earth line (WP2). The foundation of the project is the manual inspection and analysis of the STEREO/HI data to identify and catalogue all CMEs in the heliosphere from April 2007 to February 2017 (Version 4, released 2017-04-06). This is the HICAT catalogue, currently with 1,601 entries. Once identified, events are labelled with a unique ID, and the date, time, spacecraft, CME position angles and event quality are listed. HICAT has become the official and definitive event list of the STEREO/HI instruments and, as such, the lists will be maintained and updated by the STEREO project after the completion of the HELCATS project. Events will continue to be included as the STEREO mission continues, and inclusion of HICAT as the official event list through the STEREO project ensures wide community use of the catalogue. Clicking on a listed event opens up an event data page for the selected CME. (Catalogue doi 10.6084/m9.figshare.1492351).
• HIJoinCAT – Identifying CMEs in HICAT detected by STEREO-A and STEREO-B (WP2). HIJoinCAT comes from manual inspection of the STEREO-A and STEREO-B events in the HICAT database, and through the comparison of locations and timing, identifies events that are seen from both spacecraft. This identifies CMEs that can be analysed by stereoscopic means, i.e. from widely separated platforms. Version 1 was released o n 2017-04-20 and it contains 546 entries.
• HIGeoCAT - Extends the HICAT catalogue through the addition of kinematic parameters from geometrical modelling (WP3). HIGeoCAT takes all of the HICAT CMEs for which geomagnetic modelling can be employed, to derive and list kinematic parameters, such as speed and 3D direction, and projected onset times. Later work, using the in-situ observations of CME arrivals at Earth, is used to validate the models. The HIGeoCAT catalogue is also in version 4, released on 2017-04-06, and it contains 1,414 CMEs. Clicking on a listed event opens up an event data page for the selected CME. The production of the HIGeoCAT catalogue provides for the heliospheric community what the CDAW catalogue has provided for the coronal community; this is a resource that will be used extensively and is endorsed by the STEREO team. (Catalogue doi applied for).
• CACTusCAT – Provides a list of automated CME detections for comparison with the manual HICAT and HIGeoCAT catalogues (WP2). Exploiting and developing the CACTus method that has long been employed on the SOHO/LASCO coronal CME data for automated CME detection, HELCATS has demonstrated a capability for automated CME detection in HI data and favourable comparisons made with the manual methods. The current release runs from January 2007 to August 2014. A real-time version of CACTusCAT is being run by ROB at www.sidc.be/cactus/hi/.
(ii) Solar coronal and ‘surface’ events: CMEs in the corona and solaractivity (KINCAT, LOWCAT)
• KINCAT – Catalogue of coronagraph observations using the GCS model (WP3). This catalogue aims to allow a comparison of the HI-derived CME parameters of the HICAT and HIGeoCAT catalogues with an associated catalogue of coronal CME parameters. Events are identified using the STEREO/COR2 observations (1071 events in all) and the CME parameters (speed, direction, mass) derived from the application of a Graduated Cylindrical Shell model (that assumes a flux-rope topology). Some 122 events are catalogued May 2007 to December 2011 for which the GCS model could be employed. This event-set is used to make a thorough assessment of the relationship between events seen in the corona and in the heliosphere. (Catalogue doi applied for).
• LOWCAT – Catalogue of low coronal events (WP3). LOWCAT identifies events in the low corona that are associated in space and time with the projected onsets of the HI CMEs. This includes COR2 (STEREO) CMEs, along with flare, active region and filament listings. This includes entries for 1673 events.
(iii) In-situ predictions and observations of CMEs (ARRCAT, ICMECAT)
• ARRCAT – A catalogue of CME predicted arrivals (WP4). This catalogue uses the Self Similar Expansion model (see WP3 and 4 sections of the report) on the HIGeoCAT events to list the predicted arrival times of CMEs at Earth/L1, STEREO-A, STEREO-B, Venus, MESSENGER, Mars, Saturn, Ulysses, Mars Science Laboratory (MSL), MAVEN and Rosetta. ARRCAT lists some 1995 possible impacts on these targets. It is these impacts and their timings that are used later to compare with and validate the heliospheric CME models. The current version (version 1) covers the perios January 2007 to December 2015, and was released 2017-02-28. (Catalogue doi 10.6084/m9.figshare.4588324.v1).
• ICMECAT – A catalogue of in-situ CME observations (WP4). Following on from the HIGeoCAT and subsequent ARRCAT catalogues, the actual in-situ identification of CMEs at Earth/L1, STEREO-A, STEREO-B, Venus, MESSENGER, Mars, Saturn, Ulysses, Mars Science Laboratory (MSL), MAVEN and Rosetta is given in the ICMECAT catalogue. ICMECAT includes 668 events (note that many CMEs observed with HI will not impact any of the spacecraft), and was released on 2017-02-28. Parameters such as the mean magnetic field and minimum Bz component have been derived, to aid comparisons to the predicted CME arrivals. (Catalogue doi 10.6084/m9.figshare.4588315.v1).
• CORHITCAT – Catalogue of STEREO COR2 coronal CMEs with predicted arrival times at spacecraft (WP4). Complementary to the HI-related data, CORHITCAT takes the STEREO COR2 coronagraph observations to produce predictions of arrivals at different spacecraft, and compares to the in-situ events identified. This allows a comiparison of both HI and coronagraph analyses. (Catalogue doi 10.6084/m9.figshare.4903241.v1).
(iv) Linking coronal, heliospheric and in-situ catalogues (LINKCAT)
• LINKCAT – Linking the solar, heliospheric and in-situ events (WP4). LINKCAT is the glue between the coronal, heliospheric and in-situ catalogues, connecting the events that are spatially and temporally consistent. LINKCAT v1 (released 2016-07-11) includes some 143 entries, identifying the potential solar source associated activity and the parameters of the potentially associated event arrivals with each HIGeoCAT event for which such associations could be found (remembering that many of the HIGeoCAT events do not impact the spacecraft being used (near-Earth or at Mars, Venus or elsewhere). With LINKCAT, we have the first catalogue of CMEs linking from in-situ observations, through the heliosphere, the corona, and to the solar source regions. Again, linking these datasets allows a thorough test of the modelling employed in the analyses, projected to 1 AU and back-projected to the Sun. (Catalogue doi 10.6084/m9.figshare.4588330.v2).
(v) Co-rotating/Stream interaction regions (CIR/SIR) catalogue (CIRCAT)
• CIRCAT – Catalogue of co-rotating/stream interaction regions (WP5). CIRs/SIRs can be detected in the HI data through the passage of blob-like structures entrained in the interface regions. Given the experience with the CME observations within the HELCATS project, it was logical to perform a parallel study of CIR/SIRs. CIRCAT (version 2, released in 2017-03-27) provides a catalogue of the parameters of 212 events from April 2007 to August 2014. This is the first such analysis and catalogue of its kind and, as with the HI CME catalogue (HICAT/HIGeoCAT) is providing the first benchmark for studies of the phenomenon. (Catalogue doi applied for).
(vi) Solar wind background simulation database (SIMCAT)
• SIMCAT – Simulating the background solar wind (WP6). Recognising the extensive use of background solar wind simulations for space weather application, especially through the Enlil-WSA model, the HELCATS project, through WP6, attempts to simulate the background solar wind structure for advanced numerical modelling based on the kinetic properties of the CMEs and CIRs/SIRs observed and analysed through the use of HI data, rather than projected from solar magnetogram data using the so-called WSA empirical model. The simulated maps appear in the SIMCAT catalogue and it is through that catalogue that their value is assessed in comparison to the established methods.
(vii) Radio catalogues (RADCAT, IPSCAT)
• RADCAT – Cataloguing radio Type II signatures associated with CMEs (WP7). The RADCAT listing, provides a set of Type II radio events in the period March 2008 to August 2014 (March 2008 was the first event recorded; the analysis extended to earlier dates). These are Type II data recorded by the S/WAVES instrument on STEREO, in the frequency range 100 to 2000 kHz, which means that they are both coronal and heliospheric in nature and could, thus be readily associated with the HI CMEs (ground based Type II observatories cannot extend to such wavelengths and are generally only able to detect CMEs in the outer corona). RADCAT v3 (released 2016-10-19) lists parameters for 156 entries. (Catalogue doi applied for).
• IPSCAT – Catalogue of IPS events (WP7). This catalogue exploits the interplanetary scintillation (IPS) radio observations of the European EISCAT and LOFAR facilities in the detection of signatures of CMEs. It is a speculative pilot study aimed at identifying potential IPS events and comparing these to the HICAT/HIGeoCAT events to assess how well IPS techniques might work. Version 1 of the IPSCAT was released on 2017-04026. (Catalogue doi applied for).
It is the catalogue structure given here that describes the backbone of the HELCATS project; it provides facilities for future research by the community, as a clear legacy, and the published results from the project itself will spearhead the exploitation of these. The work also provides many pointers for future development, the radio studies being a good example.
Details of the work relating to the development of the catalogues and the modelling activities pertaining to each are given in the final report, which describes the Work Packages and their results in turn.
Potential Impact:
The HELCATS project has delivered what it set out to deliver. The core effort, related to the setting up and development of the catalogues, the employment of appropriate models, and the formal reporting of the activities through the defined deliverables, has been completed. The project telecons, meetings and open meetings were held as defined at the start of the project. Those deliverables that were to be delivered on completion of the project have now been completed. No aspect of the formal statement of work has not been completed.
The STFC management team and the Steering Committee take pride in the fact that the products that have been developed are unique; there is no other unified, extensive, global catalogue and analysis facility of heliospheric CMEs and CIRs/SIRs and, thus, we believe that we have delivered something that will provide a step-change in the study of solar transients in the heliosphere, enabling many lines of research for the wider community.
So, our efforts at the end of the project and into the future are to ensure that the ground-breaking facilities for research into solar transients in the heliosphere, provided by HELCATS, is well advertised and well exploited. Our strategy for this is outlined below.
1. IMPACT
From the comments, above, it is clear that we envisage a clear and significant scientific impact from the HELCATS project. In particular, the new access to extensive statistical studies, to mechanisms to link phenomena from Sun to Earth, as well as readily available access to data and to catalogued information will undoubtedly enhance many aspects of heliospheric research. The number of publications already in the open literature is testament to this. In terms of the applied side of that research, specifically for space weather, not only will the catalogues enable space-weather related research, the techniques and models applied to the HELCATS project, in particular, when making comparisons and validation, can be applied directly to space weather activities. The details of these are given in the WP descriptions but, to ensure that this has been considered fully, we defined the UK Met Office as a formal ‘interested third party’ to the HELCATS project. We believe that the project has provided assessments and tools that will be central to the development of space weather application in Europe.
Another impact of the project is the training and development of the young scientists (detailed below) and the influence that the HELCATS project has on the research they take forward. The uniqueness of the project plus its applicability to the emerging space weather programme in Europe (in particular the ESA SSA space weather programme) has provided excellent training for that emerging field. In parallel, the collaborations that have developed in the conceptual phase of HELCATS and in the running of the project have cemented new cross-disciplinary collaborations in heliospheric research.
2. LEGACY
The HELCATS team have always been fully aware of the need for a legacy plan, to ensure that the successful delivery of HELCATS includes a strategy to ensure that the products and findings are exploited fully into the future. We have been well aware of past EU projects that have not been particularly well set-up to deliver benefits for the wider community into the future, and this is something that we have taken great pains to avoid. Our plan has always included a number of elements that amount to a legacy policy with regard to the continuation of the catalogues and access to them, to the post-project state of the website, to publications – especially what we regard to be key project publications, to the development of people, in particular young scientists, and to the public. These are detailed below, and are consistent with our original proposal.
(i) Catalogues and the HELCATS website
The catalogues produced by the HELCATS project will continue to be available through the HELCATS website. The website will be maintained under the auspices of the UK Solar System Data Centre (UKSSDC) at RAL (STFC). The NASA STEREO project continues and the HI PI team at RAL will maintain and continue to expand the HICAT and HIGeoCAT catalogues as the official event lists of the HI project, adding new events as the mission progresses. Benefiting from the development work of HELCATS, the HI Post Launch Support operation at RAL will ensure that this is done. On completion of the mission these catalogues will be a formal facility within the UKSSDC for public use. However, we do not anticipate termination of STEREO in the foreseeable future, especially in the light of its value for space weather application. It is important to note that, as the Principal Investigator team for the STEREO/HI instruments, the RAL group has defined HICAT and HIGeoCAT as the definitive event lists to the wider heliospheric physics research community; they are the benchmark catalogues that the community will now use.
The website has been a working website for the project and, on completion of the project will be transitioned to a legacy portal for the HELCATS project information, as well as access to the catalogues and publications. The web address with remain as www.helcats-fp7.eu and it will be hosted at RAL.
Formal ownership or responsibility for maintaining these facilities and access to them will be taken up by the RAL STEREO/HI team within the RAL Space Physics and Operations Division.
(ii) Publications and presentations
The HELCATS website will provide access to the project publication list, containing all publications that related to the development of the project and to exploitation of the results of the project during its lifetime.
In terms of publication strategy, the project team regard the publication, on completion of the project, of key papers as being of critical importance for advertising the results of HELCATS, the facilities available and the future legacy. The final production of these will follow on immediately from completion of this report, though these papers are in a near-final in-preparation stage at this time. Submission prior to the completion of the project would have been counter-productive; our aim was to ensure that the catalogues were complete and final links accurate. These papers will be submitted to relevant professional journals, and made available on the website. This includes a definitive HELCATS project publication, and two publications that describe and detail the HICAT and HIGeoCAT catalogues and their results, especially with the presentation of the statistical analysis of CMEs in the heliosphere. Other papers will be included, and the intention has been to draft these as the project is completed so they include the important and up to date information on the data-sets themselves, access to data and final results. Whereas the HELCATS website is the shop-window or ‘one stop shop’ for the study of CMEs and CIRs/SIRs in the heliosphere, those key papers will provide the public advertisement of the facility and its exploitation. Those key papers will be widely distributed and they will be highly visible on the website.
The exploitation of the HELCATS catalogues will be intimately associated with the continued research relating, in particular, to the STEREO project. As a result, HELCATS will feature widely in the future analysis and exploitation of STEREO and the publications listed on the STEREO webpages. We anticipate extensive use of the HELCATS facilities in much the same way that the CDAW catalogues are associated with the SOHO mission research activities.
HELCATS publications are given in section 5 of the final report and summarised in Table 4.1. In section 5, the key papers are shown in italics and, if they include definitive work on particular catalogues, these are indicated.
HELCATS-related publications (see section 5 for details)(status as of 1 June 2017)
Year Number of papers*
2014 3
2015 7
2016 16
2017 (up to June 1st) 5
In preparation and submitted 16
Total 47
[* Only full papers included, not published abstracts]
The HELCATS project, progress and results have been presented at a wide range of national and international meetings. These include oral and poster presentations, as listed in section 5 of the report. As an illustration, the team gave 19 oral presentations in international conferences in seven different countries. In the same period, 40 HELCATS posters were presented. It was the active engagement and interest of the community at such meetings that stressed to the Steering Committee that holding the final Open Workshop in Vienna at the EGU meeting would be beneficial from a community point of view.
(iii) People
The HELCATS project is a collaboration of eight European groups that are front-runners in heliospheric research. The STFC management team and the Steering Committee are made up of individuals with a wide-ranging expertise in solar, heliospheric and space environment sciences, including space weather, along with instrumentation and modelling interests. That collaboration has spawned research activities that are crossing traditional disciplinary boundaries. Thus, the spirit of the HELCATS concept has been to develop a strategic approach for the field by opening new multi-disciplinary approaches. The legacy of this will live on as the scientific collaborations develop between the groups and beyond. This is well illustrated by the publications that have been produced to date.
In particular, we have recognised that HELCATS is valuable for the training of the next generation and have been particularly sensitive to the employment of young scientists who, it is hoped, will continue to develop the field or will move into related areas. In this respect we feel that HELCATS has been particularly successful. Guided by the senior players in the project, a large portion of the work has been undertaken by the younger scientists who were employed on the project, and they have had the opportuinity to present and publish their work. We identify them below. These are all scientists that completed their PhDs within the last few years or are doing their PhD studies at this time. Only a few of them were 100% funded by HELCATS and some of the PhD students were not funded by HELCATS but contributed through their supervisors. Thus, we have a spectrum of involvement, from research through to substantial modelling or cataloguing work:
Julius Achenbach, UGOE – Student at Göttingen, finishing up his masters degree with the HELCATS team, worked on the programming of the CME database.
Dr David Barnes, STFC – Employed at RAL from 2014, working on the HICAT and HIGeoCAT development and analysis. Completed his PhD in 2016 and is now in a permanent position at RAL.
Dr Peter Boakes, UNIGRAZ – Employed as postdoc on the HELCATS project in Graz. He recently moved on to work on the Rosetta/MIDAS project.
Dr Eckart Bosman, UGOE – Worked on forward modelling (GCS), finishing in January 2017 to take up a position in Graz.
Anthony Bourdelle, UPS – A SUPAERO/Master student, did an internship at UPS and then at RAL, working on the HELCATS project. He is now doing a PhD at ONERA, the French aerospace lab in Toulouse.
Bram Bourgoignie, ROB – Early career IT position working on the CACTus software.
Dr Jason Byrne, STFC - Came as a postdoc to RAL from the University of Hawaii (also formally from Trinity College Dublin), to work on HELCATS, as a young, established solar physicist. Worked on the catalogue development and analysis. Left in 2016 to work at the UK Post Office.
Dr Eoin Carley, TCD – Worked as postdoc on TCD solar associations. Left to take up Marie-Curie Fellowship and now a Postdoc at TCD.
Dr Andy Davos, ROB – Employed on project as postdoc until June 2016. Left science afterwards.
Dr Simon Good, IMPERIAL – Taken up short term contract to replace Vratislav Krupar to the end of the project, from February to April 2017.
Skralan Hosteaux, ROB – First year PhD student working on HELCATS project at ROB.
Dr Alexey Isavnin, UH - Obtained his PhD at Helsinki in 2014 and worked as a postdoc directly on the HELCATS project on issues related to the in-situ analysis and modelling.
Dr Vratislav Krupar, IMPERIAL – Employed as a postdoc to work on the radio analysis work at Imperial College, from 2015-2016. Has taken up a position at the NASA Goddard Space Flight Center, USA.
Michael Lavarra, UPS - Did a six-month internship and is now doing his Masters project after graduating from SUPAERO. He will begin a CNES-funded PhD under Alexis Rouillard’s supervision starting in September on modelling the solar wind.
Niclas Mrotzek, UGOE – PhD student working at Göttingen, working on GCS modelling. Nearing submission.
Dr Sophie Murray, TCD – Worked at TCD and the UK Met Office before returning to TCD to work on the HELCATS project and the H2020 FLARECAST project.
Erika Palmerio, UH – Has worked extensively on the HELCATS catalogues within the UH group, now working towards her PhD. Also visiting ROB for one month during Spring 2017.
Dr Rui Pinto, UPS - Did his third postdoc with UPS and will continue on a 1-year space-weather project funded by CNES with Alexis Rouillard in the coming months.
Dr Illya Plotnikov, UPS - Was hired after his PhD (in astrophysics) to work on the HELCATS project. He learnt about heliophysics with UPS, obtained French nationality last year, and will start a 3-year postdoc at Princeton in September 2017.
Adam Pluta, UGOE – PhD student working at Göttingen, nearing submission.
Dr Martin Reiss, UNIGRAZ – Worked on HELCATS during the last two months, specifically on the WP4 publication and is applying to work at the NASA Goddard Space Flight Center, USA.
Eduardo Sanchez-Diaz, UPS - Completing his PhD thesis, involving HELCATS exploitation, that he will submit in July and defend in November. He has two HELCATS papers published, one will soon be submitted and one is in preparation.
Dr Pietro Zucca, TCD – Worked as a postdoc on the TCD solar association and inverse modelling activities. Now employed as a Postdoc at the Observatoire de Paris.
(iv) The public
HELCATS is a project that is geared towards enabling extensive exploitation of heliospheric phenomena such as CMEs and CIRs/SIRs. So, its prime aim is to deliver to the scientific research community and, in turn, to provide a valuable resource for space weather application. However, we have always been aware of the need to deliver to the public that ultimately funded the project and, we are aware, has an interest in matters relating to space.
The HELCATS website is publically available and includes basic descriptions of the project, aimed at the general reader, as well as a gallery and links to associated material (e.g. the STEREO project). We have also released occasional press releases (see the website for details) and HELCATS has been included in many public talks given by the team. However, the principal public deliverable is a final report on the project, to be delivered on completion of the project. This public report contains basic information on the project, detailing links to the website and other relevant sites, and including images (and links to movies). The public report is a formal deliverable of the project; it will be distributed widely. Despite completion of the project at the end of April (at the EGU meeting), the release of this public report and any associated press material has been delayed by the call, in the UK, of a General Election. As a Government laboratory RAL/STFC is formally ‘in purdah’, meaning that the staff cannot communicate with the media (to avoid any implication of matters that might relate to the political parties in the UK). Thus, the formal release to the media will take place after the June election. This was reported at the HELCATS Final Review in April.
The final report will be made available (with any sensitive information removed) for the public and scientific community, through the website.
It is anticipated that shorter versions of the report will be used to report on completion of the project through, for example, the RAS Astronomy and Geophysics magazine and similar journals.
3. LESSONS LEARNT
The HELCATS project has been an extremely rewarding activity with the principal lessons learnt being associated with the ability to accelerate the advancing of the field through the active collaboration of a wide range of disciplines. Whilst the HELCATS concept was being developed, prior to the FP7 submission, the team were of the view that whereas many space-related FP7 projects were providing portals for access to data from a range of space instruments, the aims were often not particularly focused and a number of projects were providing very similar products. We always felt that HELCATS provided a particular focus, on the identification, cataloguing and modelling of transients in the heliosphere and that this focus not only made the project unique, it gave it a clear scientific aim that was both manageable and valuable.
With hindsight, a number of activities on the administrative side could have been improved. For example, we defined the 18 month milestone and the end of the project as the two financial reporting periods. Thus, for each we required a financial report associated with a report on progress of the project. Noting that we also had full project annual reports at 12 and 24 months, this called for rather more, full, formal reports on the project than was anticipated. We tackled this by requesting that one of the annual reports could be converted to the production of the definitive HELCATS paper (which is in effect a full report but for publication purposes). Noting also that the financial reports, by necessity were generated after the milestones, it might have been better to disconnect the annual project reports and the financial reports, to be delivered as separate documents a few months apart.
Having said that, the communication structure of monthly telecons, bi-annual and annual meetings ensured that the groups were well integrated and that the project ran smoothly. With the number of deliverables and actions, it was essential to maintain good minutes of meetings and lodge them on the Wiki area of the website.
A particular lesson for us relates to the activity at the completion of the project. Many deliverables, such as the final catalogues were formally to be delivered in month 36, and a number of reports at about the same time. This does mean that our desire to publish the definitive HELCATS paper plus a few key project papers on the catalogues could really only be finalised right at the end of the project or the weeks after. Early publication could easily result in incomplete information. The decision was made early to not finalise those publications until month 36.
We believe that our approach to the legacy of the project is critical, having witnessed past projects pass into obscurity. We feel that the formal links to the UKSSDC and the STEREO project, ensuring that the catalogues and website are maintained into the foreseeable future, will enable the benefits of HELCATS to be widely exploited. In this respect, we would be happy to provide a legacy report to the EU some six months after the completion of the project, to demonatrate that the legacy strategy is working, and would suggest that such a legacy report some time after the completion of any such project would be valuable.
List of Websites:
https://www.helcats-fp7.eu/
Main contact: Professor Richard A Harrison, RAL Space, STFC Rutherford Appleton Laboratory, Harwell, Oxfordshire OX11 0QX, UK [01235446884)
e-mail: Richard.harrison@stfc.ac.uk
The advent of wide-angle imaging of the inner heliosphere has revolutionised the study of the solar wind and, in particular, transient solar wind structures such as Coronal Mass Ejections (CMEs) and Co-rotating Interaction Regions (CIRs). CMEs comprise enormous plasma and magnetic field structures that are ejected from the Sun and propagate at what can be immense speeds through interplanetary space, whilst CIRs are characterised by extensive swathes of compressed plasma/magnetic field that form along flow discontinuities of solar origin that permeate the inner heliosphere. With Heliospheric Imaging (HI) came the unique ability to track the evolution of these features as they propagate through the inner heliosphere. Prior to the development of wide-angle imaging of the inner heliosphere, signatures of such solar wind transients could only be observed within a few solar radii of the Sun, and in the vicinity of a few near-Earth and interplanetary in-situ probes. HI has, for the first time, filled that vast and crucial observational gap. Recognising that a number of lines of research have addressed the deceleration and deflection of CMEs and interaction between CMEs and between CMEs and CIRs, and that considerable evolution of a CME can be witnessed in the HI images during its passage through the heliosphere, exploiting the HI images in studying the propagation of CMEs through the heliosphere must become an essential element of future space weather application; it is not acceptable to simply rely on knowledge of the passage of a CME through the corona and await its arrival at 1 AU.
The HELCATS project provides an unprecedented focus for world-leading European expertise in the novel and revolutionary, European-led field of HI, in terms of instrumentation, data analysis, modelling and science. HELCATS is a strategic project that empowers the wider scientific community, in Europe and beyond, by providing access to advanced catalogues - validated and augmented through the use of techniques and models - for the analysis of solar wind transients, based on observations from European-led space instrumentation. All of the beneficiaries are at the forefront of heliospheric research and bring distinct, yet highly complementary, skills to the project. HELCATS adds significant value to the exploitation of existing European space instrumentation, providing a strong foundation for enhanced exploitation and advancement of European heliospheric research.
HELCATS recognises the synergy between solar and heliospheric physics research (both of which are European strengths) and their applied space weather aspect, currently a topic of vigorous debate in many political and scientific arenas. With the current development of a European space weather capability, within ESA’s Space Situational Awareness programme, HELCATS has real, practical relevance. Certainly the HI concept is high on the priority lists for the payloads of missions that are being defined at this time, and the exploitation of those instruments, for the detection and analysis of potentially Earth-impacting events, will be significantly enhanced by the outcome of the HELCATS project studies, in defining methods and models for adoption.
The HELCATS consortium is led by STFC’s Rutherford Appleton Laboratory. The Coordinator is Professor Richard A Harrison, the Scientific Manager is Dr Jackie A Davies, and the Technical Manager is Dr Chris Perry. The fundamental aim of the HELCATS project is to start with heliospheric imaging observations and, from that, build up facilities, methods and assessment studies in a logical programme of activities. The work is managed by STFC, involving a total of eight European research groups, or beneficiaries. The activities of the beneficiaries are tailored to their scientific and technical strengths, maximizing the potential scientific return for the project.
The list of beneficiaries includes the Science and Technology Facilities Council (STFC), United Kingdom, the University of Graz (UNIGRAZ), Austria, the University of Paul Sabatier (UPS), France, the University of Goettingen, (UGOE), Germany, the Royal Observatory Belgium (ROB), Belgium, Imperial College London (IMPERIAL), United Kingdom, University of Helsinki (UH), Finland and Trinity College Dublin (TCD), Ireland. Key to the success of HELCATS has been the combination of space-hardware, observations, data, theory, modelling, across a critical range of solar and heliospheric disciplines, that the beneficiary group provides. In addition, the HELCATS project includes two third parties, not shown in the table; this includes George Mason University (USA), to enable close modelling ties between UPS and the developer of the Enlil model that is used extensively in some aspects of the project. The second is CNRS, which is the employer of the key staff at UPS; CNRS is included as a formal third party for managerial reasons rather than direct input to the project.
Project Context and Objectives:
The concept for this project comes out of the recognition that there is potential for adding considerable value - for scientific exploitation and space weather studies alike - by pooling the considerable and world-leading European expertise in this field (in terms of science, instrumentation, modelling, etc). A programme of cataloguing, modelling validation and information provision would clearly bolster community-wide research into the physics of the heliosphere – the volume of space in which we live. Our aim is to enhance considerably the European lead in this key area of science research by applying a coordinated approach to the provision of techniques, tools, and data access. This goes beyond providing post-launch support for the STEREO instruments alone and beyond the individual research interests of groups around Europe.
The following headline activities form the basic set of objectives for the HELCATS project. The relevant Work Packages (WPs), tasks and deliverables are listed below. We note the relevant WPs here:
• Production of the first comprehensive catalogue of CMEs in the heliosphere for the period from 2007, using manual recognition of CMEs in STEREO/HI data but also assessing the potential for automatic CME recognition. (WP2).
• The generation (and inclusion in the catalogue), for those CMEs, of parameters such as radial speed, 3-dimensional (3-D) trajectory, orientation, projected launch time, and projected arrival times at various locations in the heliosphere, in particular Earth and other planets. This would be achieved through the application of a range of models (geometric and forward). The net result of these activities would be the provision of a unique and comprehensive facility for characterising transient activity in the heliosphere and, in particular, Earth-impacting CMEs. (WP3).
• Production of the first comprehensive catalogue of CIRs, including their modelled kinematic and spatial properties, from STEREO/HI data using manual recognition (over the same period). (WP5).
• Comparison with solar ‘source’ and in-situ data in order to correlate the white-light imagery with activity on the Sun and at various locations in the heliosphere (such as Earth and other planets), thereby providing validation of the models. (WP4, WP5).
• The application of global numerical modelling, that also allows an assessment of the potential for driving such models (widely used for space weather applications) based on HI data. (WP6).
• The assessment of the potential for combining white-light imaging of the inner heliosphere with ground- and space-based radio data, in particular Interplanetary Scintillation (IPS) and Type II radio bursts; catalogues of such radio events will be produced as required. (WP7).
• The dissemination of the aforementioned results, not only through publications emanating from the consortium but also from members of the broader scientific community through providing them with easy access to the catalogues/methodologies; the latter will enable a much wider exploitation and understanding of the HELCATS results. (WP8).
In terms of the practical application of the project, the work was managed through eight well-defined workpackages as listed below:
WP1: Management - The HELCATS consortium includes 8 European groups from 7 EU countries and two third parties. The project coordinates work involving observations, cataloguing, modelling, and studies in validation and assessment. WP1 covers the formal management roles of the HELCATS project. This includes administrative tasks, maintaining project infrastructure, coordinating inputs and reporting as required and handling a range of project issues. WP1 oversees the website production and management.
WP2: Producing a definitive catalogue of CMEs imaged by STEREO/HI - This WP provides the foundation for this project (including scientific coordination), namely the production of a catalogue of CMEs in the heliosphere. The catalogue is produced from manual inspection of STEREO/HI data but use of automated techniques has been investigated, allowing the manual and automated methods to be compared. Comparisons with coronal (coronagraph) CME catalogues have also been made, to compare the detection and analysis of CMEs in the corona with those detected in the solar wind.
WP3: Deriving/cataloguing the kinematic properties of STEREO/HI CMEs based on geometrical and forward modelling - Here we apply recently established geometrical, forward and (prototype) inverse modelling methods to derive CME parameters, which are added to the catalogue (including back- and forward-projections to ‘predict’ CME launch and arrivals at various Solar System locations). Comparisons have been made between the parameters yielded by the different models.
WP4: Verifying the kinematic properties of STEREO/HI CMEs against in-situ CME observations and coronal sources - This WP catalogues in-situ CME information (at Earth and elsewhere) for comparison to the projected data from WP3 in order to assess the performance of the aforementioned models. Similarly, comparisons are made with solar ‘surface’ phenomena. These allow a thorough validation of the models.
WP5: Producing a definitive catalogue of CIRs imaged by STEREO/HI that includes verified model-derived kinematic properties - In parallel with the CME cataloguing, modelling and model assessment in WP2-4, this WP performs an analogous activity for CIRs, again with cataloguing, geometrical modelling and the validation of results through comparisons to in-situ/solar data.
WP6: Initialising advanced numerical models based on the kinematic properties of STEREO/HI CMEs and CIRs - This WP recognises the potential for using HI data as input to numerical MHD models of the heliosphere (in terms of both CME and CIR phenomena) by considering the use of HI images for initialisation/driving of the ENLIL model. The results are compared to traditional methods for running such models, based on coronal and photospheric inputs, to assess their potential.
WP7: Assessing the complementary nature of radio measurements of solar wind transients - WP7 explores the value of incorporating radio observations, to augment the HI data. It assesses the value of using interplanetary scintillation (IPS) observations and Type II radio burst data in conjunction with HI data, both of which can provide additional information.
WP8: Dissemination - WP8 brings the results to the community through (1) the publication of results in the open, refereed literature, (2) the running of annual open meetings, (3) the installation of all relevant documentation, catalogues and reports on the website and (4) the dissemination of information to the public and policy makers. This includes ingestion of the products into the AMDA data-mining tool the IRAP (UPS) propagation tool, and integration with projects such as HELIO. This WP coordinates the exploitation of the project outputs, such that they feed into numerous research activities and future space weather applications.
Overall, the HELCATS strategy is to coordinate a range of observational and modelling studies of heliospheric phenomena to provide a foundation for enhancing the scientific discipline and the exploitation of European investment in the hardware involved. It is also a benchmark in the provision of facilities to understand the nature and development of solar transients in the heliosphere.
Full details of the HELCATS project can be seen in the description of work documents (606692_DOW_PART_A.pdf and 606692_DOW_PARTB.pdf) agreed with the European Commission in early 2014. Those documents also outline the resources per beneficiary, and by WP, in terms of finance and staff time. In terms of the productivity of HELCATS we do stress that the project was designed to provide a unique, timely facility for the research community, to drive a significantly better understanding of solar-generated transients and their passage through the heliosphere, as well as their sources and impacts. Thus, in keeping with the spirit of many EU projects, the aim is to provide the legacy of a thorough, global catalogue of heliospheric transients, that has previously not been available, and, in doing so, assess and validate a range of available models. The project is not a portal allowing use of a number of space-related data-bases; it is built on a specific instrumental and observational strength in heliospheric imaging, with the analysis and modelling activities that provide a global view of solar transients in the heliosphere that has not existed before. The project has added significant value to existing facilities and is clearly of direct interest to space weather applications in the near future. However, in providing the facilities (catalogues) and the assessment and exploitation of different models and methods, the project clearly provides a facility that is valuable to the wider research community and is not per se, a research project in itself. The basic aim was to deliver a legacy that can enable major scientific steps. Nevertheless, many of the results are published in the scientific literature and these are noted in the text and included in the publication list.
Project Results:
One of the international benchmarks for CME research is the CDAW (Coordinated Data Analysis Workshops) catalogue of events identified in the SOHO/LASCO coronagraph data (see https://cdaw.gsfc.nasa.gov/CME_list/). This facility has provided the gold standard in event identification and in enabling a wide range of investigations that have advanced the field of CME research considerably over the past 20 years. It does not replace the research; it enables the research by providing access to the event listings and the data, as well as basic analysis of the kinematics. The CDAW/LASCO event list is referenced directly in a large number of research papers. All of this relates to the passage of solar ejecta through the corona.
With the advent of the STEREO/HI instruments (Eyles et al., 2009), following on from the Coriolis/SMEI instrument, we are now observing CMEs in the heliosphere on a regular basis, well beyond the limits of LASCO’s field of view, and through interplanetary space to beyond 1 AU. The STEREO/HI instruments are led by RAL Space (STFC). Whilst recognising the value of heliospheric CME investigations to fundamental research, we also note the requirements of the space weather community, and these both stress the need for a similar benchmark facility for heliospheric CMEs. Hence, the concept behind HELCATS was born.
In many ways, the HI instrumentation and the HELCATS project work focus on the fact that prior to the advent of heliospheric imaging, CMEs could be observed in the corona but were then not detected until and unless they passed over spacecraft with in-situ instrumentation. As mentioned above, we recognise a 200 Rs ‘gap’ in observational capability that has now been closed. Tracking CMEs and studying their structure and evolution in the inner heliosphere enables studies of a wide range of issues such as CME onset and Earth arrival studies, CME-CME interaction, CME deceleration and deflection, the shock-CME relationship, and studies of other transients such as SIRs/CIRs. The value of such work for space weather impacts is clear, as is the opening of this vast new region for fundamental research into heliospheric physics. Thus, the value of HI observations is clearly of great importance for heliophysics research as well as space weather interests.
The HELCATS project work-plan outlined a set of clear elements and results, defined very much through the unique set of catalogues that have been subsequently developed, as detailed in the bullets, below. All of the catalogues mentioned are accessible through the HELCATS website, using the PRODUCTS tab. We group the catalogues for clarity:
(i) Heliospheric Imaging of CMEs (HICAT, HIGeoCAT and CACTusCAT)
• HICAT – The first definitive catalogue of CMEs in the heliosphere from outside the Sun-Earth line (WP2). The foundation of the project is the manual inspection and analysis of the STEREO/HI data to identify and catalogue all CMEs in the heliosphere from April 2007 to February 2017 (Version 4, released 2017-04-06). This is the HICAT catalogue, currently with 1,601 entries. Once identified, events are labelled with a unique ID, and the date, time, spacecraft, CME position angles and event quality are listed. HICAT has become the official and definitive event list of the STEREO/HI instruments and, as such, the lists will be maintained and updated by the STEREO project after the completion of the HELCATS project. Events will continue to be included as the STEREO mission continues, and inclusion of HICAT as the official event list through the STEREO project ensures wide community use of the catalogue. Clicking on a listed event opens up an event data page for the selected CME. (Catalogue doi 10.6084/m9.figshare.1492351).
• HIJoinCAT – Identifying CMEs in HICAT detected by STEREO-A and STEREO-B (WP2). HIJoinCAT comes from manual inspection of the STEREO-A and STEREO-B events in the HICAT database, and through the comparison of locations and timing, identifies events that are seen from both spacecraft. This identifies CMEs that can be analysed by stereoscopic means, i.e. from widely separated platforms. Version 1 was released o n 2017-04-20 and it contains 546 entries.
• HIGeoCAT - Extends the HICAT catalogue through the addition of kinematic parameters from geometrical modelling (WP3). HIGeoCAT takes all of the HICAT CMEs for which geomagnetic modelling can be employed, to derive and list kinematic parameters, such as speed and 3D direction, and projected onset times. Later work, using the in-situ observations of CME arrivals at Earth, is used to validate the models. The HIGeoCAT catalogue is also in version 4, released on 2017-04-06, and it contains 1,414 CMEs. Clicking on a listed event opens up an event data page for the selected CME. The production of the HIGeoCAT catalogue provides for the heliospheric community what the CDAW catalogue has provided for the coronal community; this is a resource that will be used extensively and is endorsed by the STEREO team. (Catalogue doi applied for).
• CACTusCAT – Provides a list of automated CME detections for comparison with the manual HICAT and HIGeoCAT catalogues (WP2). Exploiting and developing the CACTus method that has long been employed on the SOHO/LASCO coronal CME data for automated CME detection, HELCATS has demonstrated a capability for automated CME detection in HI data and favourable comparisons made with the manual methods. The current release runs from January 2007 to August 2014. A real-time version of CACTusCAT is being run by ROB at www.sidc.be/cactus/hi/.
(ii) Solar coronal and ‘surface’ events: CMEs in the corona and solaractivity (KINCAT, LOWCAT)
• KINCAT – Catalogue of coronagraph observations using the GCS model (WP3). This catalogue aims to allow a comparison of the HI-derived CME parameters of the HICAT and HIGeoCAT catalogues with an associated catalogue of coronal CME parameters. Events are identified using the STEREO/COR2 observations (1071 events in all) and the CME parameters (speed, direction, mass) derived from the application of a Graduated Cylindrical Shell model (that assumes a flux-rope topology). Some 122 events are catalogued May 2007 to December 2011 for which the GCS model could be employed. This event-set is used to make a thorough assessment of the relationship between events seen in the corona and in the heliosphere. (Catalogue doi applied for).
• LOWCAT – Catalogue of low coronal events (WP3). LOWCAT identifies events in the low corona that are associated in space and time with the projected onsets of the HI CMEs. This includes COR2 (STEREO) CMEs, along with flare, active region and filament listings. This includes entries for 1673 events.
(iii) In-situ predictions and observations of CMEs (ARRCAT, ICMECAT)
• ARRCAT – A catalogue of CME predicted arrivals (WP4). This catalogue uses the Self Similar Expansion model (see WP3 and 4 sections of the report) on the HIGeoCAT events to list the predicted arrival times of CMEs at Earth/L1, STEREO-A, STEREO-B, Venus, MESSENGER, Mars, Saturn, Ulysses, Mars Science Laboratory (MSL), MAVEN and Rosetta. ARRCAT lists some 1995 possible impacts on these targets. It is these impacts and their timings that are used later to compare with and validate the heliospheric CME models. The current version (version 1) covers the perios January 2007 to December 2015, and was released 2017-02-28. (Catalogue doi 10.6084/m9.figshare.4588324.v1).
• ICMECAT – A catalogue of in-situ CME observations (WP4). Following on from the HIGeoCAT and subsequent ARRCAT catalogues, the actual in-situ identification of CMEs at Earth/L1, STEREO-A, STEREO-B, Venus, MESSENGER, Mars, Saturn, Ulysses, Mars Science Laboratory (MSL), MAVEN and Rosetta is given in the ICMECAT catalogue. ICMECAT includes 668 events (note that many CMEs observed with HI will not impact any of the spacecraft), and was released on 2017-02-28. Parameters such as the mean magnetic field and minimum Bz component have been derived, to aid comparisons to the predicted CME arrivals. (Catalogue doi 10.6084/m9.figshare.4588315.v1).
• CORHITCAT – Catalogue of STEREO COR2 coronal CMEs with predicted arrival times at spacecraft (WP4). Complementary to the HI-related data, CORHITCAT takes the STEREO COR2 coronagraph observations to produce predictions of arrivals at different spacecraft, and compares to the in-situ events identified. This allows a comiparison of both HI and coronagraph analyses. (Catalogue doi 10.6084/m9.figshare.4903241.v1).
(iv) Linking coronal, heliospheric and in-situ catalogues (LINKCAT)
• LINKCAT – Linking the solar, heliospheric and in-situ events (WP4). LINKCAT is the glue between the coronal, heliospheric and in-situ catalogues, connecting the events that are spatially and temporally consistent. LINKCAT v1 (released 2016-07-11) includes some 143 entries, identifying the potential solar source associated activity and the parameters of the potentially associated event arrivals with each HIGeoCAT event for which such associations could be found (remembering that many of the HIGeoCAT events do not impact the spacecraft being used (near-Earth or at Mars, Venus or elsewhere). With LINKCAT, we have the first catalogue of CMEs linking from in-situ observations, through the heliosphere, the corona, and to the solar source regions. Again, linking these datasets allows a thorough test of the modelling employed in the analyses, projected to 1 AU and back-projected to the Sun. (Catalogue doi 10.6084/m9.figshare.4588330.v2).
(v) Co-rotating/Stream interaction regions (CIR/SIR) catalogue (CIRCAT)
• CIRCAT – Catalogue of co-rotating/stream interaction regions (WP5). CIRs/SIRs can be detected in the HI data through the passage of blob-like structures entrained in the interface regions. Given the experience with the CME observations within the HELCATS project, it was logical to perform a parallel study of CIR/SIRs. CIRCAT (version 2, released in 2017-03-27) provides a catalogue of the parameters of 212 events from April 2007 to August 2014. This is the first such analysis and catalogue of its kind and, as with the HI CME catalogue (HICAT/HIGeoCAT) is providing the first benchmark for studies of the phenomenon. (Catalogue doi applied for).
(vi) Solar wind background simulation database (SIMCAT)
• SIMCAT – Simulating the background solar wind (WP6). Recognising the extensive use of background solar wind simulations for space weather application, especially through the Enlil-WSA model, the HELCATS project, through WP6, attempts to simulate the background solar wind structure for advanced numerical modelling based on the kinetic properties of the CMEs and CIRs/SIRs observed and analysed through the use of HI data, rather than projected from solar magnetogram data using the so-called WSA empirical model. The simulated maps appear in the SIMCAT catalogue and it is through that catalogue that their value is assessed in comparison to the established methods.
(vii) Radio catalogues (RADCAT, IPSCAT)
• RADCAT – Cataloguing radio Type II signatures associated with CMEs (WP7). The RADCAT listing, provides a set of Type II radio events in the period March 2008 to August 2014 (March 2008 was the first event recorded; the analysis extended to earlier dates). These are Type II data recorded by the S/WAVES instrument on STEREO, in the frequency range 100 to 2000 kHz, which means that they are both coronal and heliospheric in nature and could, thus be readily associated with the HI CMEs (ground based Type II observatories cannot extend to such wavelengths and are generally only able to detect CMEs in the outer corona). RADCAT v3 (released 2016-10-19) lists parameters for 156 entries. (Catalogue doi applied for).
• IPSCAT – Catalogue of IPS events (WP7). This catalogue exploits the interplanetary scintillation (IPS) radio observations of the European EISCAT and LOFAR facilities in the detection of signatures of CMEs. It is a speculative pilot study aimed at identifying potential IPS events and comparing these to the HICAT/HIGeoCAT events to assess how well IPS techniques might work. Version 1 of the IPSCAT was released on 2017-04026. (Catalogue doi applied for).
It is the catalogue structure given here that describes the backbone of the HELCATS project; it provides facilities for future research by the community, as a clear legacy, and the published results from the project itself will spearhead the exploitation of these. The work also provides many pointers for future development, the radio studies being a good example.
Details of the work relating to the development of the catalogues and the modelling activities pertaining to each are given in the final report, which describes the Work Packages and their results in turn.
Potential Impact:
The HELCATS project has delivered what it set out to deliver. The core effort, related to the setting up and development of the catalogues, the employment of appropriate models, and the formal reporting of the activities through the defined deliverables, has been completed. The project telecons, meetings and open meetings were held as defined at the start of the project. Those deliverables that were to be delivered on completion of the project have now been completed. No aspect of the formal statement of work has not been completed.
The STFC management team and the Steering Committee take pride in the fact that the products that have been developed are unique; there is no other unified, extensive, global catalogue and analysis facility of heliospheric CMEs and CIRs/SIRs and, thus, we believe that we have delivered something that will provide a step-change in the study of solar transients in the heliosphere, enabling many lines of research for the wider community.
So, our efforts at the end of the project and into the future are to ensure that the ground-breaking facilities for research into solar transients in the heliosphere, provided by HELCATS, is well advertised and well exploited. Our strategy for this is outlined below.
1. IMPACT
From the comments, above, it is clear that we envisage a clear and significant scientific impact from the HELCATS project. In particular, the new access to extensive statistical studies, to mechanisms to link phenomena from Sun to Earth, as well as readily available access to data and to catalogued information will undoubtedly enhance many aspects of heliospheric research. The number of publications already in the open literature is testament to this. In terms of the applied side of that research, specifically for space weather, not only will the catalogues enable space-weather related research, the techniques and models applied to the HELCATS project, in particular, when making comparisons and validation, can be applied directly to space weather activities. The details of these are given in the WP descriptions but, to ensure that this has been considered fully, we defined the UK Met Office as a formal ‘interested third party’ to the HELCATS project. We believe that the project has provided assessments and tools that will be central to the development of space weather application in Europe.
Another impact of the project is the training and development of the young scientists (detailed below) and the influence that the HELCATS project has on the research they take forward. The uniqueness of the project plus its applicability to the emerging space weather programme in Europe (in particular the ESA SSA space weather programme) has provided excellent training for that emerging field. In parallel, the collaborations that have developed in the conceptual phase of HELCATS and in the running of the project have cemented new cross-disciplinary collaborations in heliospheric research.
2. LEGACY
The HELCATS team have always been fully aware of the need for a legacy plan, to ensure that the successful delivery of HELCATS includes a strategy to ensure that the products and findings are exploited fully into the future. We have been well aware of past EU projects that have not been particularly well set-up to deliver benefits for the wider community into the future, and this is something that we have taken great pains to avoid. Our plan has always included a number of elements that amount to a legacy policy with regard to the continuation of the catalogues and access to them, to the post-project state of the website, to publications – especially what we regard to be key project publications, to the development of people, in particular young scientists, and to the public. These are detailed below, and are consistent with our original proposal.
(i) Catalogues and the HELCATS website
The catalogues produced by the HELCATS project will continue to be available through the HELCATS website. The website will be maintained under the auspices of the UK Solar System Data Centre (UKSSDC) at RAL (STFC). The NASA STEREO project continues and the HI PI team at RAL will maintain and continue to expand the HICAT and HIGeoCAT catalogues as the official event lists of the HI project, adding new events as the mission progresses. Benefiting from the development work of HELCATS, the HI Post Launch Support operation at RAL will ensure that this is done. On completion of the mission these catalogues will be a formal facility within the UKSSDC for public use. However, we do not anticipate termination of STEREO in the foreseeable future, especially in the light of its value for space weather application. It is important to note that, as the Principal Investigator team for the STEREO/HI instruments, the RAL group has defined HICAT and HIGeoCAT as the definitive event lists to the wider heliospheric physics research community; they are the benchmark catalogues that the community will now use.
The website has been a working website for the project and, on completion of the project will be transitioned to a legacy portal for the HELCATS project information, as well as access to the catalogues and publications. The web address with remain as www.helcats-fp7.eu and it will be hosted at RAL.
Formal ownership or responsibility for maintaining these facilities and access to them will be taken up by the RAL STEREO/HI team within the RAL Space Physics and Operations Division.
(ii) Publications and presentations
The HELCATS website will provide access to the project publication list, containing all publications that related to the development of the project and to exploitation of the results of the project during its lifetime.
In terms of publication strategy, the project team regard the publication, on completion of the project, of key papers as being of critical importance for advertising the results of HELCATS, the facilities available and the future legacy. The final production of these will follow on immediately from completion of this report, though these papers are in a near-final in-preparation stage at this time. Submission prior to the completion of the project would have been counter-productive; our aim was to ensure that the catalogues were complete and final links accurate. These papers will be submitted to relevant professional journals, and made available on the website. This includes a definitive HELCATS project publication, and two publications that describe and detail the HICAT and HIGeoCAT catalogues and their results, especially with the presentation of the statistical analysis of CMEs in the heliosphere. Other papers will be included, and the intention has been to draft these as the project is completed so they include the important and up to date information on the data-sets themselves, access to data and final results. Whereas the HELCATS website is the shop-window or ‘one stop shop’ for the study of CMEs and CIRs/SIRs in the heliosphere, those key papers will provide the public advertisement of the facility and its exploitation. Those key papers will be widely distributed and they will be highly visible on the website.
The exploitation of the HELCATS catalogues will be intimately associated with the continued research relating, in particular, to the STEREO project. As a result, HELCATS will feature widely in the future analysis and exploitation of STEREO and the publications listed on the STEREO webpages. We anticipate extensive use of the HELCATS facilities in much the same way that the CDAW catalogues are associated with the SOHO mission research activities.
HELCATS publications are given in section 5 of the final report and summarised in Table 4.1. In section 5, the key papers are shown in italics and, if they include definitive work on particular catalogues, these are indicated.
HELCATS-related publications (see section 5 for details)(status as of 1 June 2017)
Year Number of papers*
2014 3
2015 7
2016 16
2017 (up to June 1st) 5
In preparation and submitted 16
Total 47
[* Only full papers included, not published abstracts]
The HELCATS project, progress and results have been presented at a wide range of national and international meetings. These include oral and poster presentations, as listed in section 5 of the report. As an illustration, the team gave 19 oral presentations in international conferences in seven different countries. In the same period, 40 HELCATS posters were presented. It was the active engagement and interest of the community at such meetings that stressed to the Steering Committee that holding the final Open Workshop in Vienna at the EGU meeting would be beneficial from a community point of view.
(iii) People
The HELCATS project is a collaboration of eight European groups that are front-runners in heliospheric research. The STFC management team and the Steering Committee are made up of individuals with a wide-ranging expertise in solar, heliospheric and space environment sciences, including space weather, along with instrumentation and modelling interests. That collaboration has spawned research activities that are crossing traditional disciplinary boundaries. Thus, the spirit of the HELCATS concept has been to develop a strategic approach for the field by opening new multi-disciplinary approaches. The legacy of this will live on as the scientific collaborations develop between the groups and beyond. This is well illustrated by the publications that have been produced to date.
In particular, we have recognised that HELCATS is valuable for the training of the next generation and have been particularly sensitive to the employment of young scientists who, it is hoped, will continue to develop the field or will move into related areas. In this respect we feel that HELCATS has been particularly successful. Guided by the senior players in the project, a large portion of the work has been undertaken by the younger scientists who were employed on the project, and they have had the opportuinity to present and publish their work. We identify them below. These are all scientists that completed their PhDs within the last few years or are doing their PhD studies at this time. Only a few of them were 100% funded by HELCATS and some of the PhD students were not funded by HELCATS but contributed through their supervisors. Thus, we have a spectrum of involvement, from research through to substantial modelling or cataloguing work:
Julius Achenbach, UGOE – Student at Göttingen, finishing up his masters degree with the HELCATS team, worked on the programming of the CME database.
Dr David Barnes, STFC – Employed at RAL from 2014, working on the HICAT and HIGeoCAT development and analysis. Completed his PhD in 2016 and is now in a permanent position at RAL.
Dr Peter Boakes, UNIGRAZ – Employed as postdoc on the HELCATS project in Graz. He recently moved on to work on the Rosetta/MIDAS project.
Dr Eckart Bosman, UGOE – Worked on forward modelling (GCS), finishing in January 2017 to take up a position in Graz.
Anthony Bourdelle, UPS – A SUPAERO/Master student, did an internship at UPS and then at RAL, working on the HELCATS project. He is now doing a PhD at ONERA, the French aerospace lab in Toulouse.
Bram Bourgoignie, ROB – Early career IT position working on the CACTus software.
Dr Jason Byrne, STFC - Came as a postdoc to RAL from the University of Hawaii (also formally from Trinity College Dublin), to work on HELCATS, as a young, established solar physicist. Worked on the catalogue development and analysis. Left in 2016 to work at the UK Post Office.
Dr Eoin Carley, TCD – Worked as postdoc on TCD solar associations. Left to take up Marie-Curie Fellowship and now a Postdoc at TCD.
Dr Andy Davos, ROB – Employed on project as postdoc until June 2016. Left science afterwards.
Dr Simon Good, IMPERIAL – Taken up short term contract to replace Vratislav Krupar to the end of the project, from February to April 2017.
Skralan Hosteaux, ROB – First year PhD student working on HELCATS project at ROB.
Dr Alexey Isavnin, UH - Obtained his PhD at Helsinki in 2014 and worked as a postdoc directly on the HELCATS project on issues related to the in-situ analysis and modelling.
Dr Vratislav Krupar, IMPERIAL – Employed as a postdoc to work on the radio analysis work at Imperial College, from 2015-2016. Has taken up a position at the NASA Goddard Space Flight Center, USA.
Michael Lavarra, UPS - Did a six-month internship and is now doing his Masters project after graduating from SUPAERO. He will begin a CNES-funded PhD under Alexis Rouillard’s supervision starting in September on modelling the solar wind.
Niclas Mrotzek, UGOE – PhD student working at Göttingen, working on GCS modelling. Nearing submission.
Dr Sophie Murray, TCD – Worked at TCD and the UK Met Office before returning to TCD to work on the HELCATS project and the H2020 FLARECAST project.
Erika Palmerio, UH – Has worked extensively on the HELCATS catalogues within the UH group, now working towards her PhD. Also visiting ROB for one month during Spring 2017.
Dr Rui Pinto, UPS - Did his third postdoc with UPS and will continue on a 1-year space-weather project funded by CNES with Alexis Rouillard in the coming months.
Dr Illya Plotnikov, UPS - Was hired after his PhD (in astrophysics) to work on the HELCATS project. He learnt about heliophysics with UPS, obtained French nationality last year, and will start a 3-year postdoc at Princeton in September 2017.
Adam Pluta, UGOE – PhD student working at Göttingen, nearing submission.
Dr Martin Reiss, UNIGRAZ – Worked on HELCATS during the last two months, specifically on the WP4 publication and is applying to work at the NASA Goddard Space Flight Center, USA.
Eduardo Sanchez-Diaz, UPS - Completing his PhD thesis, involving HELCATS exploitation, that he will submit in July and defend in November. He has two HELCATS papers published, one will soon be submitted and one is in preparation.
Dr Pietro Zucca, TCD – Worked as a postdoc on the TCD solar association and inverse modelling activities. Now employed as a Postdoc at the Observatoire de Paris.
(iv) The public
HELCATS is a project that is geared towards enabling extensive exploitation of heliospheric phenomena such as CMEs and CIRs/SIRs. So, its prime aim is to deliver to the scientific research community and, in turn, to provide a valuable resource for space weather application. However, we have always been aware of the need to deliver to the public that ultimately funded the project and, we are aware, has an interest in matters relating to space.
The HELCATS website is publically available and includes basic descriptions of the project, aimed at the general reader, as well as a gallery and links to associated material (e.g. the STEREO project). We have also released occasional press releases (see the website for details) and HELCATS has been included in many public talks given by the team. However, the principal public deliverable is a final report on the project, to be delivered on completion of the project. This public report contains basic information on the project, detailing links to the website and other relevant sites, and including images (and links to movies). The public report is a formal deliverable of the project; it will be distributed widely. Despite completion of the project at the end of April (at the EGU meeting), the release of this public report and any associated press material has been delayed by the call, in the UK, of a General Election. As a Government laboratory RAL/STFC is formally ‘in purdah’, meaning that the staff cannot communicate with the media (to avoid any implication of matters that might relate to the political parties in the UK). Thus, the formal release to the media will take place after the June election. This was reported at the HELCATS Final Review in April.
The final report will be made available (with any sensitive information removed) for the public and scientific community, through the website.
It is anticipated that shorter versions of the report will be used to report on completion of the project through, for example, the RAS Astronomy and Geophysics magazine and similar journals.
3. LESSONS LEARNT
The HELCATS project has been an extremely rewarding activity with the principal lessons learnt being associated with the ability to accelerate the advancing of the field through the active collaboration of a wide range of disciplines. Whilst the HELCATS concept was being developed, prior to the FP7 submission, the team were of the view that whereas many space-related FP7 projects were providing portals for access to data from a range of space instruments, the aims were often not particularly focused and a number of projects were providing very similar products. We always felt that HELCATS provided a particular focus, on the identification, cataloguing and modelling of transients in the heliosphere and that this focus not only made the project unique, it gave it a clear scientific aim that was both manageable and valuable.
With hindsight, a number of activities on the administrative side could have been improved. For example, we defined the 18 month milestone and the end of the project as the two financial reporting periods. Thus, for each we required a financial report associated with a report on progress of the project. Noting that we also had full project annual reports at 12 and 24 months, this called for rather more, full, formal reports on the project than was anticipated. We tackled this by requesting that one of the annual reports could be converted to the production of the definitive HELCATS paper (which is in effect a full report but for publication purposes). Noting also that the financial reports, by necessity were generated after the milestones, it might have been better to disconnect the annual project reports and the financial reports, to be delivered as separate documents a few months apart.
Having said that, the communication structure of monthly telecons, bi-annual and annual meetings ensured that the groups were well integrated and that the project ran smoothly. With the number of deliverables and actions, it was essential to maintain good minutes of meetings and lodge them on the Wiki area of the website.
A particular lesson for us relates to the activity at the completion of the project. Many deliverables, such as the final catalogues were formally to be delivered in month 36, and a number of reports at about the same time. This does mean that our desire to publish the definitive HELCATS paper plus a few key project papers on the catalogues could really only be finalised right at the end of the project or the weeks after. Early publication could easily result in incomplete information. The decision was made early to not finalise those publications until month 36.
We believe that our approach to the legacy of the project is critical, having witnessed past projects pass into obscurity. We feel that the formal links to the UKSSDC and the STEREO project, ensuring that the catalogues and website are maintained into the foreseeable future, will enable the benefits of HELCATS to be widely exploited. In this respect, we would be happy to provide a legacy report to the EU some six months after the completion of the project, to demonatrate that the legacy strategy is working, and would suggest that such a legacy report some time after the completion of any such project would be valuable.
List of Websites:
https://www.helcats-fp7.eu/
Main contact: Professor Richard A Harrison, RAL Space, STFC Rutherford Appleton Laboratory, Harwell, Oxfordshire OX11 0QX, UK [01235446884)
e-mail: Richard.harrison@stfc.ac.uk
