Periodic Reporting for period 1 - DUSTBUSTERS (Dust and gas in planet forming discs)
Berichtszeitraum: 2019-01-01 bis 2022-09-30
Since the dawn of mankind, people have asked fundamental questions such as how did our home, the Earth, come into place and whether we are or not alone in the Universe. Now, science is able to start addressing such questions, by observing planets around stars different than our Sun and by directly observing the process of planet formation as it happens. Such studies are able to deeply affect the perception of our place in the Universe.
Planet formation is a widespread by-product of the process of star formation itself and occurs within relatively thin and dense protostellar discs made of gas and dust that orbit the newborn star. Such discs can now be probed with unprecedented detail thanks to high-resolution telescopes and instruments, such as the Atacama Large Millimeter Array (ALMA) at sub-millimeter wavelengths or the SPHERE instrument at the Very large telescope (VLT) in the near-infrared, which are both capable of probing nearby star formation regions with a spatial resolution of a few astronomical units. Such new observations are literally revolutionizing our understanding of such discs. We now know that their geometry can be quite complex, characterized by substructures such as rings and gaps, spirals, crescent-like features, mysterious shadows. All such features require a proper understanding from a physical and dynamic point of view. In addition, the long-term processes that lead to the evolution of the disc: viscous accretion, planet formation, photoevaporation, are now being all reconsidered in terms of timescales and their effects on disc properties.
The overall aim of this project is to strengthen the collaboration of groups located in Europe, USA, Chile and Australia - many of them already collaborating actively - in order to (1) develop and use suitable numerical algorithms and techniques to address key unsolved issues related to the interaction of newborn planets with the gas and dust environment in which they are born and (2) to compare such models with the most advanced observations of protostellar discs, obtained with high-resolution telescopes in the IR and sub-mm.
Planet formation is a widespread by-product of the process of star formation itself and occurs within relatively thin and dense protostellar discs made of gas and dust that orbit the newborn star. Such discs can now be probed with unprecedented detail thanks to high-resolution telescopes and instruments, such as the Atacama Large Millimeter Array (ALMA) at sub-millimeter wavelengths or the SPHERE instrument at the Very large telescope (VLT) in the near-infrared, which are both capable of probing nearby star formation regions with a spatial resolution of a few astronomical units. Such new observations are literally revolutionizing our understanding of such discs. We now know that their geometry can be quite complex, characterized by substructures such as rings and gaps, spirals, crescent-like features, mysterious shadows. All such features require a proper understanding from a physical and dynamic point of view. In addition, the long-term processes that lead to the evolution of the disc: viscous accretion, planet formation, photoevaporation, are now being all reconsidered in terms of timescales and their effects on disc properties.
The overall aim of this project is to strengthen the collaboration of groups located in Europe, USA, Chile and Australia - many of them already collaborating actively - in order to (1) develop and use suitable numerical algorithms and techniques to address key unsolved issues related to the interaction of newborn planets with the gas and dust environment in which they are born and (2) to compare such models with the most advanced observations of protostellar discs, obtained with high-resolution telescopes in the IR and sub-mm.
During the first effective 33 months of the project (12 months of suspension due to covid 19 pandemic have been subtracted), 27 researchers, both early-stage and experienced, had the opportunity to travel across the Dustbusters’ nodes to collaborate trough 33 secondments, with a total duration of 52, 69 person months, sharing their knowledge and experiences. Once back in their Sending Institutions they actively continued interacting, producing more than 170 of published papers, deepening thus our understanding of protoplanetary discs and their evolution.
In particular, new observational data have been acquired using the most advanced facilities such as ALMA, X-Shooter and SPHERE. These data have been analyzed and new methods for the post process of images have been developed. From a theoretical point of view, many codes have been tested, compared and then used to produce new simulations of real astronomical sources.
The main outcome of the first Dustbusters reportig period has therefore been the strengthening of the collaboration of theorists and observers from all over the world, in order to address key unresolved issues related to the formation of planets in protoplanetary discs and their interaction with the host star.
In particular, new observational data have been acquired using the most advanced facilities such as ALMA, X-Shooter and SPHERE. These data have been analyzed and new methods for the post process of images have been developed. From a theoretical point of view, many codes have been tested, compared and then used to produce new simulations of real astronomical sources.
The main outcome of the first Dustbusters reportig period has therefore been the strengthening of the collaboration of theorists and observers from all over the world, in order to address key unresolved issues related to the formation of planets in protoplanetary discs and their interaction with the host star.
The advent of ALMA and other facilities has marked a revolution in our understanding of protostellar disc dynamics. For decades, models of protostellar discs were very simple, mostly axisymmetric models, and often assumed that gas and dust were perfectly mixed. We now know that these discs are very often characterized by prominent substructures such as gaps, spirals, rings and many more.
Such structures can be caused by many different physical processes, either related to instabilities in the disc or (perhaps more interestingly) to the presence of newly born planets.
Thanks to the state of the art telescopes we will obtain exceptionally high-resolution observations of individual discs and large surveys of star-forming regions, to compare with simulations performed with the most advanced numerical codes to simulate planet-disc interaction in protostellar discs. This interplay between theory and observations will provide a significant step forward in our understanding of the dynamics of protostellar discs and in particular on the processes that lead to the formation of planets.
Such structures can be caused by many different physical processes, either related to instabilities in the disc or (perhaps more interestingly) to the presence of newly born planets.
Thanks to the state of the art telescopes we will obtain exceptionally high-resolution observations of individual discs and large surveys of star-forming regions, to compare with simulations performed with the most advanced numerical codes to simulate planet-disc interaction in protostellar discs. This interplay between theory and observations will provide a significant step forward in our understanding of the dynamics of protostellar discs and in particular on the processes that lead to the formation of planets.