Project acronym A-BINGOS
Project Accreting binary populations in Nearby Galaxies: Observations and Simulations
Researcher (PI) Andreas Zezas
Host Institution (HI) IDRYMA TECHNOLOGIAS KAI EREVNAS
Country Greece
Call Details Consolidator Grant (CoG), PE9, ERC-2013-CoG
Summary "High-energy observations of our Galaxy offer a good, albeit not complete, picture of the X-ray source populations, in particular the accreting binary sources. Recent ability to study accreting binaries in nearby galaxies has shown that we would be short-sighted if we restricted ourselves to our Galaxy or to a few nearby ones. I propose an ambitious project that involves a comprehensive study of all the galaxies within 10 Mpc for which we can study in detail their X-ray sources and stellar populations. The study will combine data from a unique suite of observatories (Chandra, XMM-Newton, HST, Spitzer) with state-of-the-art theoretical modelling of binary systems. I propose a novel approach that links the accreting binary populations to their parent stellar populations and surpasses any current studies of X-ray binary populations, both in scale and in scope, by: (a) combining methods and results from several different areas of astrophysics (compact objects, binary systems, stellar populations, galaxy evolution); (b) using data from almost the whole electromagnetic spectrum (infrared to X-ray bands); (c) identifying and studying the different sub-populations of accreting binaries; and (d) performing direct comparison between observations and theoretical predictions, over a broad parameter space. The project: (a) will answer the long-standing question of the formation efficiency of accreting binaries in different environments; and (b) will constrain their evolutionary paths. As by-products the project will provide eagerly awaited input to the fields of gravitational-wave sources, γ-ray bursts, and X-ray emitting galaxies at cosmological distances and it will produce a heritage multi-wavelength dataset and library of models for future studies of galaxies and accreting binaries."
Summary
"High-energy observations of our Galaxy offer a good, albeit not complete, picture of the X-ray source populations, in particular the accreting binary sources. Recent ability to study accreting binaries in nearby galaxies has shown that we would be short-sighted if we restricted ourselves to our Galaxy or to a few nearby ones. I propose an ambitious project that involves a comprehensive study of all the galaxies within 10 Mpc for which we can study in detail their X-ray sources and stellar populations. The study will combine data from a unique suite of observatories (Chandra, XMM-Newton, HST, Spitzer) with state-of-the-art theoretical modelling of binary systems. I propose a novel approach that links the accreting binary populations to their parent stellar populations and surpasses any current studies of X-ray binary populations, both in scale and in scope, by: (a) combining methods and results from several different areas of astrophysics (compact objects, binary systems, stellar populations, galaxy evolution); (b) using data from almost the whole electromagnetic spectrum (infrared to X-ray bands); (c) identifying and studying the different sub-populations of accreting binaries; and (d) performing direct comparison between observations and theoretical predictions, over a broad parameter space. The project: (a) will answer the long-standing question of the formation efficiency of accreting binaries in different environments; and (b) will constrain their evolutionary paths. As by-products the project will provide eagerly awaited input to the fields of gravitational-wave sources, γ-ray bursts, and X-ray emitting galaxies at cosmological distances and it will produce a heritage multi-wavelength dataset and library of models for future studies of galaxies and accreting binaries."
Max ERC Funding
1 242 000 €
Duration
Start date: 2014-04-01, End date: 2019-03-31
Project acronym AEONS
Project Advancing the Equation of state of Neutron Stars
Researcher (PI) Anna WATTS
Host Institution (HI) UNIVERSITEIT VAN AMSTERDAM
Country Netherlands
Call Details Consolidator Grant (CoG), PE9, ERC-2019-COG
Summary Densities in neutron star (NS) cores can reach up to ten times the density of a normal atomic nucleus, and the stabilising effect of gravitational confinement permits long-timescale weak interactions. This generates nucleonic matter that is extremely neutron-rich, and the exciting possibility of stable states of strange matter (hyperons or deconfined quarks). Our uncertainty about the nature of cold ultradense matter is encoded in the Equation of State (EOS), which can be mapped via the stellar structure equations to quantities like mass M and radius R that determine the exterior space-time.
One very promising technique for measuring the EOS exploits hotspots that form on the NS surface due to the pulsar mechanism, accretion streams, or during thermonuclear explosions in the stellar ocean. As the NS rotates, the hotspot gives rise to a pulsation and relativistic effects encode information about the EOS into the pulse profile. Pulse Profile Modelling (PPM), which employs relativistic ray-tracing and Bayesian inference codes to measure M-R and the EOS, is being pioneered by NASA’s NICER telescope, which is poised to deliver its first results in 2019.
Complexities, that have only become apparent with exposure to real data, mean that there is work to be done if we are to have confidence in the nominal 5-10% accuracy of NICER’s M-R results. AEONS will deliver this. The project will also look ahead to the next generation of large-area X-ray timing telescopes, since it is only then that PPM will place tight constraints on dense matter models. The sources these missions target, accreting neutron stars, pose challenges for PPM such as variability, surface pattern uncertainty, and polarimetric signatures. AEONS will develop a robust pipeline for accreting NS PPM and embed it in a multi-messenger EOS inference framework with radio and gravitational wave constraints. This will ensure that PPM delivers major advances in our understanding of the nature of matter.
Summary
Densities in neutron star (NS) cores can reach up to ten times the density of a normal atomic nucleus, and the stabilising effect of gravitational confinement permits long-timescale weak interactions. This generates nucleonic matter that is extremely neutron-rich, and the exciting possibility of stable states of strange matter (hyperons or deconfined quarks). Our uncertainty about the nature of cold ultradense matter is encoded in the Equation of State (EOS), which can be mapped via the stellar structure equations to quantities like mass M and radius R that determine the exterior space-time.
One very promising technique for measuring the EOS exploits hotspots that form on the NS surface due to the pulsar mechanism, accretion streams, or during thermonuclear explosions in the stellar ocean. As the NS rotates, the hotspot gives rise to a pulsation and relativistic effects encode information about the EOS into the pulse profile. Pulse Profile Modelling (PPM), which employs relativistic ray-tracing and Bayesian inference codes to measure M-R and the EOS, is being pioneered by NASA’s NICER telescope, which is poised to deliver its first results in 2019.
Complexities, that have only become apparent with exposure to real data, mean that there is work to be done if we are to have confidence in the nominal 5-10% accuracy of NICER’s M-R results. AEONS will deliver this. The project will also look ahead to the next generation of large-area X-ray timing telescopes, since it is only then that PPM will place tight constraints on dense matter models. The sources these missions target, accreting neutron stars, pose challenges for PPM such as variability, surface pattern uncertainty, and polarimetric signatures. AEONS will develop a robust pipeline for accreting NS PPM and embed it in a multi-messenger EOS inference framework with radio and gravitational wave constraints. This will ensure that PPM delivers major advances in our understanding of the nature of matter.
Max ERC Funding
2 425 000 €
Duration
Start date: 2020-06-01, End date: 2025-05-31
Project acronym AEROSOL
Project Astrochemistry of old stars: direct probing of unique chemical laboratories
Researcher (PI) Leen Katrien Els Decin
Host Institution (HI) KATHOLIEKE UNIVERSITEIT LEUVEN
Country Belgium
Call Details Consolidator Grant (CoG), PE9, ERC-2014-CoG
Summary The gas and dust in the interstellar medium (ISM) drive the chemical evolution of galaxies, the formation of stars and planets, and the synthesis of complex prebiotic molecules. The prime birth places for this interstellar material are the winds of evolved (super)giant stars. These winds are unique chemical laboratories, in which a large variety of gas and dust species radially expand away from the star.
Recent progress on the observations of these winds has been impressive thanks to Herschel and ALMA. The next challenge is to unravel the wealth of chemical information contained in these data. This is an ambitious task since (1) a plethora of physical and chemical processes interact in a complex way, (2) laboratory data to interpret these interactions are lacking, and (3) theoretical tools to analyse the data do not meet current needs.
To boost the knowledge of the physics and chemistry characterizing these winds, I propose a world-leading multi-disciplinary project combining (1) high-quality data, (2) novel theoretical wind models, and (3) targeted laboratory experiments. The aim is to pinpoint the dominant chemical pathways, unravel the transition from gas-phase to dust species, elucidate the role of clumps on the overall wind structure, and study the reciprocal effect between various dynamical and chemical phenomena.
Now is the right time for this ambitious project thanks to the availability of (1) high-quality multi-wavelength data, including ALMA and Herschel data of the PI, (2) supercomputers enabling a homogeneous analysis of the data using sophisticated theoretical wind models, and (3) novel laboratory equipment to measure the gas-phase reaction rates of key species.
This project will have far-reaching impact on (1) the field of evolved stars, (2) the understanding of the chemical lifecycle of the ISM, (3) chemical studies of dynamically more complex systems, such as exoplanets, protostars, supernovae etc., and (4) it will guide new instrument development.
Summary
The gas and dust in the interstellar medium (ISM) drive the chemical evolution of galaxies, the formation of stars and planets, and the synthesis of complex prebiotic molecules. The prime birth places for this interstellar material are the winds of evolved (super)giant stars. These winds are unique chemical laboratories, in which a large variety of gas and dust species radially expand away from the star.
Recent progress on the observations of these winds has been impressive thanks to Herschel and ALMA. The next challenge is to unravel the wealth of chemical information contained in these data. This is an ambitious task since (1) a plethora of physical and chemical processes interact in a complex way, (2) laboratory data to interpret these interactions are lacking, and (3) theoretical tools to analyse the data do not meet current needs.
To boost the knowledge of the physics and chemistry characterizing these winds, I propose a world-leading multi-disciplinary project combining (1) high-quality data, (2) novel theoretical wind models, and (3) targeted laboratory experiments. The aim is to pinpoint the dominant chemical pathways, unravel the transition from gas-phase to dust species, elucidate the role of clumps on the overall wind structure, and study the reciprocal effect between various dynamical and chemical phenomena.
Now is the right time for this ambitious project thanks to the availability of (1) high-quality multi-wavelength data, including ALMA and Herschel data of the PI, (2) supercomputers enabling a homogeneous analysis of the data using sophisticated theoretical wind models, and (3) novel laboratory equipment to measure the gas-phase reaction rates of key species.
This project will have far-reaching impact on (1) the field of evolved stars, (2) the understanding of the chemical lifecycle of the ISM, (3) chemical studies of dynamically more complex systems, such as exoplanets, protostars, supernovae etc., and (4) it will guide new instrument development.
Max ERC Funding
2 605 897 €
Duration
Start date: 2016-01-01, End date: 2021-12-31
Project acronym ALERT
Project ALERT - The Apertif-LOFAR Exploration of the Radio Transient Sky
Researcher (PI) Albert Van Leeuwen
Host Institution (HI) STICHTING ASTRON, NETHERLANDS INSTITUTE FOR RADIO ASTRONOMY
Country Netherlands
Call Details Consolidator Grant (CoG), PE9, ERC-2013-CoG
Summary "In our largely unchanging radio Universe, a highly dynamic component was recently discovered: flashes of bright radio emission that last only milliseconds but appear all over the sky. Some of these radio bursts can be traced to intermittently pulsating neutron stars. Other bursts however, apparently originate far outside our Galaxy. Due to great observational challenges, the evolution of the neutron stars is not understood, while more importantly, the nature of the extragalactic bursts remains an outright mystery.
My overall aim is to understand the physics that drives both kinds of brief and luminous bursts.
My primary goal is to identify the highly compact astrophysical explosions powering the extragalactic bursts. My previous surveys are the state of the art in fast-transient detection; I will now increase by a factor of 10 this exploration volume. In real-time I will provide arcsec positions, 10,000-fold more accurate than currently possible, to localize such extragalactic bursts for the first time and understand their origin.
My secondary goal is to unravel the unexplained evolution of intermittently pulsating neutron stars (building on e.g., my recent papers in Science, 2013), by doubling their number and modeling their population.
To achieve these goals, I will carry out a highly innovative survey: the Apertif-LOFAR Exploration of the Radio Transient Sky. ALERT is over an order of magnitude more sensitive than all current state-of-the art fast-transient surveys.
Through its novel, extremely wide field-of-view, Westerbork/Apertif will detect many tens of extragalactic bursts. Through real-time triggers to LOFAR I will next provide the precise localisation that is essential for radio, optical and high-energy follow-up to, for the first time, shed light on the physics and objects driving these bursts – evaporating primordial black holes; explosions in host galaxies; or, the unknown?"
Summary
"In our largely unchanging radio Universe, a highly dynamic component was recently discovered: flashes of bright radio emission that last only milliseconds but appear all over the sky. Some of these radio bursts can be traced to intermittently pulsating neutron stars. Other bursts however, apparently originate far outside our Galaxy. Due to great observational challenges, the evolution of the neutron stars is not understood, while more importantly, the nature of the extragalactic bursts remains an outright mystery.
My overall aim is to understand the physics that drives both kinds of brief and luminous bursts.
My primary goal is to identify the highly compact astrophysical explosions powering the extragalactic bursts. My previous surveys are the state of the art in fast-transient detection; I will now increase by a factor of 10 this exploration volume. In real-time I will provide arcsec positions, 10,000-fold more accurate than currently possible, to localize such extragalactic bursts for the first time and understand their origin.
My secondary goal is to unravel the unexplained evolution of intermittently pulsating neutron stars (building on e.g., my recent papers in Science, 2013), by doubling their number and modeling their population.
To achieve these goals, I will carry out a highly innovative survey: the Apertif-LOFAR Exploration of the Radio Transient Sky. ALERT is over an order of magnitude more sensitive than all current state-of-the art fast-transient surveys.
Through its novel, extremely wide field-of-view, Westerbork/Apertif will detect many tens of extragalactic bursts. Through real-time triggers to LOFAR I will next provide the precise localisation that is essential for radio, optical and high-energy follow-up to, for the first time, shed light on the physics and objects driving these bursts – evaporating primordial black holes; explosions in host galaxies; or, the unknown?"
Max ERC Funding
1 999 823 €
Duration
Start date: 2014-12-01, End date: 2020-11-30
Project acronym ArcheoDyn
Project Globular clusters as living fossils of the past of galaxies
Researcher (PI) Petrus VAN DE VEN
Host Institution (HI) UNIVERSITAT WIEN
Country Austria
Call Details Consolidator Grant (CoG), PE9, ERC-2016-COG
Summary Globular clusters (GCs) are enigmatic objects that hide a wealth of information. They are the living fossils of the history of their native galaxies and the record keepers of the violent events that made them change their domicile. This proposal aims to mine GCs as living fossils of galaxy evolution to address fundamental questions in astrophysics: (1) Do satellite galaxies merge as predicted by the hierarchical build-up of galaxies? (2) Which are the seeds of supermassive black holes in the centres of galaxies? (3) How did star formation originate in the earliest phases of galaxy formation? To answer these questions, novel population-dependent dynamical modelling techniques are required, whose development the PI has led over the past years. This uniquely positions him to take full advantage of the emerging wealth of chemical and kinematical data on GCs.
Following the tidal disruption of satellite galaxies, their dense GCs, and maybe even their nuclei, are left as the most visible remnants in the main galaxy. The hierarchical build-up of their new host galaxy can thus be unearthed by recovering the GCs’ orbits. However, currently it is unclear which of the GCs are accretion survivors. Actually, the existence of a central intermediate mass black hole (IMBH) or of multiple stellar populations in GCs might tell which ones are accreted. At the same time, detection of IMBHs is important as they are predicted seeds for supermassive black holes in galaxies; while the multiple stellar populations in GCs are vital witnesses to the extreme modes of star formation in the early Universe. However, for every putative dynamical IMBH detection so far there is a corresponding non-detection; also the origin of multiple stellar populations in GCs still lacks any uncontrived explanation. The synergy of novel techniques and exquisite data proposed here promises a breakthrough in this emerging field of dynamical archeology with GCs as living fossils of the past of galaxies.
Summary
Globular clusters (GCs) are enigmatic objects that hide a wealth of information. They are the living fossils of the history of their native galaxies and the record keepers of the violent events that made them change their domicile. This proposal aims to mine GCs as living fossils of galaxy evolution to address fundamental questions in astrophysics: (1) Do satellite galaxies merge as predicted by the hierarchical build-up of galaxies? (2) Which are the seeds of supermassive black holes in the centres of galaxies? (3) How did star formation originate in the earliest phases of galaxy formation? To answer these questions, novel population-dependent dynamical modelling techniques are required, whose development the PI has led over the past years. This uniquely positions him to take full advantage of the emerging wealth of chemical and kinematical data on GCs.
Following the tidal disruption of satellite galaxies, their dense GCs, and maybe even their nuclei, are left as the most visible remnants in the main galaxy. The hierarchical build-up of their new host galaxy can thus be unearthed by recovering the GCs’ orbits. However, currently it is unclear which of the GCs are accretion survivors. Actually, the existence of a central intermediate mass black hole (IMBH) or of multiple stellar populations in GCs might tell which ones are accreted. At the same time, detection of IMBHs is important as they are predicted seeds for supermassive black holes in galaxies; while the multiple stellar populations in GCs are vital witnesses to the extreme modes of star formation in the early Universe. However, for every putative dynamical IMBH detection so far there is a corresponding non-detection; also the origin of multiple stellar populations in GCs still lacks any uncontrived explanation. The synergy of novel techniques and exquisite data proposed here promises a breakthrough in this emerging field of dynamical archeology with GCs as living fossils of the past of galaxies.
Max ERC Funding
1 999 250 €
Duration
Start date: 2017-09-01, End date: 2022-08-31
Project acronym ASSESS
Project Episodic Mass Loss in the Most Massive Stars: Key to Understanding the Explosive Early Universe
Researcher (PI) Alceste BONANOS
Host Institution (HI) ETHNIKO ASTEROSKOPEIO ATHINON
Country Greece
Call Details Consolidator Grant (CoG), PE9, ERC-2017-COG
Summary Massive stars dominate their surroundings during their short lifetimes, while their explosive deaths impact the chemical evolution and spatial cohesion of their hosts. After birth, their evolution is largely dictated by their ability to remove layers of hydrogen from their envelopes. Multiple lines of evidence are pointing to violent, episodic mass-loss events being responsible for removing a large part of the massive stellar envelope, especially in low-metallicity galaxies. Episodic mass loss, however, is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We aim to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We plan to (i) derive physical parameters of a large sample of dusty, evolved targets and estimate the amount of ejected mass, (ii) constrain evolutionary models, (iii) quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to existing multi-band and time-series photometry of luminous sources in ~25 nearby galaxies. Dusty, luminous evolved massive stars will thus be automatically classified and follow-up spectroscopy will be obtained for selected targets. Atmospheric and SED modeling will yield parameters and estimates of time-dependent mass loss for ~1000 luminous stars. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.
Summary
Massive stars dominate their surroundings during their short lifetimes, while their explosive deaths impact the chemical evolution and spatial cohesion of their hosts. After birth, their evolution is largely dictated by their ability to remove layers of hydrogen from their envelopes. Multiple lines of evidence are pointing to violent, episodic mass-loss events being responsible for removing a large part of the massive stellar envelope, especially in low-metallicity galaxies. Episodic mass loss, however, is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We aim to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We plan to (i) derive physical parameters of a large sample of dusty, evolved targets and estimate the amount of ejected mass, (ii) constrain evolutionary models, (iii) quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to existing multi-band and time-series photometry of luminous sources in ~25 nearby galaxies. Dusty, luminous evolved massive stars will thus be automatically classified and follow-up spectroscopy will be obtained for selected targets. Atmospheric and SED modeling will yield parameters and estimates of time-dependent mass loss for ~1000 luminous stars. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.
Max ERC Funding
1 128 750 €
Duration
Start date: 2018-09-01, End date: 2023-08-31
Project acronym Asterochronometry
Project Galactic archeology with high temporal resolution
Researcher (PI) Andrea MIGLIO
Host Institution (HI) ALMA MATER STUDIORUM - UNIVERSITA DI BOLOGNA
Country Italy
Call Details Consolidator Grant (CoG), PE9, ERC-2017-COG
Summary The Milky Way is a complex system, with dynamical and chemical substructures, where several competing processes such as mergers, internal secular evolution, gas accretion and gas flows take place. To study in detail how such a giant spiral galaxy was formed and evolved, we need to reconstruct the sequence of its main formation events with high (~10%) temporal resolution.
Asterochronometry will determine accurate, precise ages for tens of thousands of stars in the Galaxy. We will take an approach distinguished by a number of key aspects including, developing novel star-dating methods that fully utilise the potential of individual pulsation modes, coupled with a careful appraisal of systematic uncertainties on age deriving from our limited understanding of stellar physics.
We will then capitalise on opportunities provided by the timely availability of astrometric, spectroscopic, and asteroseismic data to build and data-mine chrono-chemo-dynamical maps of regions of the Milky Way probed by the space missions CoRoT, Kepler, K2, and TESS. We will quantify, by comparison with predictions of chemodynamical models, the relative importance of various processes which play a role in shaping the Galaxy, for example mergers and dynamical processes. We will use chrono-chemical tagging to look for evidence of aggregates, and precise and accurate ages to reconstruct the early star formation history of the Milky Way’s main constituents.
The Asterochronometry project will also provide stringent observational tests of stellar structure and answer some of the long-standing open questions in stellar modelling (e.g. efficiency of transport processes, mass loss on the giant branch, the occurrence of products of coalescence / mass exchange). These tests will improve our ability to determine stellar ages and chemical yields, with wide impact e.g. on the characterisation and ensemble studies of exoplanets, on evolutionary population synthesis, integrated colours and thus ages of galaxies.
Summary
The Milky Way is a complex system, with dynamical and chemical substructures, where several competing processes such as mergers, internal secular evolution, gas accretion and gas flows take place. To study in detail how such a giant spiral galaxy was formed and evolved, we need to reconstruct the sequence of its main formation events with high (~10%) temporal resolution.
Asterochronometry will determine accurate, precise ages for tens of thousands of stars in the Galaxy. We will take an approach distinguished by a number of key aspects including, developing novel star-dating methods that fully utilise the potential of individual pulsation modes, coupled with a careful appraisal of systematic uncertainties on age deriving from our limited understanding of stellar physics.
We will then capitalise on opportunities provided by the timely availability of astrometric, spectroscopic, and asteroseismic data to build and data-mine chrono-chemo-dynamical maps of regions of the Milky Way probed by the space missions CoRoT, Kepler, K2, and TESS. We will quantify, by comparison with predictions of chemodynamical models, the relative importance of various processes which play a role in shaping the Galaxy, for example mergers and dynamical processes. We will use chrono-chemical tagging to look for evidence of aggregates, and precise and accurate ages to reconstruct the early star formation history of the Milky Way’s main constituents.
The Asterochronometry project will also provide stringent observational tests of stellar structure and answer some of the long-standing open questions in stellar modelling (e.g. efficiency of transport processes, mass loss on the giant branch, the occurrence of products of coalescence / mass exchange). These tests will improve our ability to determine stellar ages and chemical yields, with wide impact e.g. on the characterisation and ensemble studies of exoplanets, on evolutionary population synthesis, integrated colours and thus ages of galaxies.
Max ERC Funding
1 958 863 €
Duration
Start date: 2018-04-01, End date: 2023-09-30
Project acronym ASTROFLOW
Project The influence of stellar outflows on exoplanetary mass loss
Researcher (PI) Aline VIDOTTO
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD, OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Country Ireland
Call Details Consolidator Grant (CoG), PE9, ERC-2018-COG
Summary ASTROFLOW aims to make ground-breaking progress in our physical understanding of exoplanetary mass loss, by quantifying the influence of stellar outflows on atmospheric escape of close-in exoplanets. Escape plays a key role in planetary evolution, population, and potential to develop life. Stellar irradiation and outflows affect planetary mass loss: irradiation heats planetary atmospheres, which inflate and more likely escape; outflows cause pressure confinement around otherwise freely escaping atmospheres. This external pressure can increase, reduce or even suppress escape rates; its effects on exoplanetary mass loss remain largely unexplored due to the complexity of such interactions. I will fill this knowledge gap by developing a novel modelling framework of atmospheric escape that will, for the first time, consider the effects of realistic stellar outflows on exoplanetary mass loss. My expertise in stellar wind theory and 3D magnetohydrodynamic simulations is crucial for producing the next-generation models of planetary escape. My framework will consist of state-of-the-art, time-dependent, 3D simulations of stellar outflows (Method 1), which will be coupled to novel 3D simulations of atmospheric escape (Method 2). My models will account for the major underlying physical processes of mass loss. With this, I will determine the response of planetary mass loss to realistic stellar particle, magnetic and radiation environments and will characterise the physical conditions of the escaping material. I will compute how its extinction varies during transit and compare synthetic line profiles to atmospheric escape observations from, eg, Hubble and our NASA cubesat CUTE. Strong synergy with upcoming observations (JWST, TESS, SPIRou, CARMENES) also exists. Determining the lifetime of planetary atmospheres is essential to understanding populations of exoplanets. ASTROFLOW’s work will be the foundation for future research of how exoplanets evolve under mass-loss processes.
Summary
ASTROFLOW aims to make ground-breaking progress in our physical understanding of exoplanetary mass loss, by quantifying the influence of stellar outflows on atmospheric escape of close-in exoplanets. Escape plays a key role in planetary evolution, population, and potential to develop life. Stellar irradiation and outflows affect planetary mass loss: irradiation heats planetary atmospheres, which inflate and more likely escape; outflows cause pressure confinement around otherwise freely escaping atmospheres. This external pressure can increase, reduce or even suppress escape rates; its effects on exoplanetary mass loss remain largely unexplored due to the complexity of such interactions. I will fill this knowledge gap by developing a novel modelling framework of atmospheric escape that will, for the first time, consider the effects of realistic stellar outflows on exoplanetary mass loss. My expertise in stellar wind theory and 3D magnetohydrodynamic simulations is crucial for producing the next-generation models of planetary escape. My framework will consist of state-of-the-art, time-dependent, 3D simulations of stellar outflows (Method 1), which will be coupled to novel 3D simulations of atmospheric escape (Method 2). My models will account for the major underlying physical processes of mass loss. With this, I will determine the response of planetary mass loss to realistic stellar particle, magnetic and radiation environments and will characterise the physical conditions of the escaping material. I will compute how its extinction varies during transit and compare synthetic line profiles to atmospheric escape observations from, eg, Hubble and our NASA cubesat CUTE. Strong synergy with upcoming observations (JWST, TESS, SPIRou, CARMENES) also exists. Determining the lifetime of planetary atmospheres is essential to understanding populations of exoplanets. ASTROFLOW’s work will be the foundation for future research of how exoplanets evolve under mass-loss processes.
Max ERC Funding
1 999 956 €
Duration
Start date: 2019-09-01, End date: 2024-08-31
Project acronym AWESoMeStars
Project Accretion, Winds, and Evolution of Spins and Magnetism of Stars
Researcher (PI) Sean Patrick Matt
Host Institution (HI) THE UNIVERSITY OF EXETER
Country United Kingdom
Call Details Consolidator Grant (CoG), PE9, ERC-2015-CoG
Summary This project focuses on Sun-like stars, which possess convective envelopes and universally exhibit magnetic activity (in the mass range 0.1 to 1.3 MSun). The rotation of these stars influences their internal structure, energy and chemical transport, and magnetic field generation, as well as their external magnetic activity and environmental interactions. Due to the huge range of timescales, spatial scales, and physics involved, understanding how each of these processes relate to each other and to the long-term evolution remains an enormous challenge in astrophysics. To face this challenge, the AWESoMeStars project will develop a comprehensive, physical picture of the evolution of stellar rotation, magnetic activity, mass loss, and accretion.
In doing so, we will
(1) Discover how stars lose the vast majority of their angular momentum, which happens in the accretion phase
(2) Explain the observed rotation-activity relationship and saturation in terms of the evolution of magnetic properties & coronal physics
(3) Characterize coronal heating and mass loss across the full range of mass & age
(4) Explain the Skumanich (1972) relationship and distributions of spin rates observed in young clusters & old field stars
(5) Develop physics-based gyrochronology as a tool for using rotation rates to constrain stellar ages.
We will accomplish these goals using a fundamentally new and multi-faceted approach, which combines the power of multi-dimensional MHD simulations with long-timescale rotational-evolution models. Specifically, we will develop a next generation of MHD simulations of both star-disk interactions and stellar winds, to model stars over the full range of mass & age, and to characterize how magnetically active stars impact their environments. Simultaneously, we will create a new class of rotational-evolution models that include external torques derived from our simulations, compute the evolution of spin rates of entire star clusters, & compare with observations.
Summary
This project focuses on Sun-like stars, which possess convective envelopes and universally exhibit magnetic activity (in the mass range 0.1 to 1.3 MSun). The rotation of these stars influences their internal structure, energy and chemical transport, and magnetic field generation, as well as their external magnetic activity and environmental interactions. Due to the huge range of timescales, spatial scales, and physics involved, understanding how each of these processes relate to each other and to the long-term evolution remains an enormous challenge in astrophysics. To face this challenge, the AWESoMeStars project will develop a comprehensive, physical picture of the evolution of stellar rotation, magnetic activity, mass loss, and accretion.
In doing so, we will
(1) Discover how stars lose the vast majority of their angular momentum, which happens in the accretion phase
(2) Explain the observed rotation-activity relationship and saturation in terms of the evolution of magnetic properties & coronal physics
(3) Characterize coronal heating and mass loss across the full range of mass & age
(4) Explain the Skumanich (1972) relationship and distributions of spin rates observed in young clusters & old field stars
(5) Develop physics-based gyrochronology as a tool for using rotation rates to constrain stellar ages.
We will accomplish these goals using a fundamentally new and multi-faceted approach, which combines the power of multi-dimensional MHD simulations with long-timescale rotational-evolution models. Specifically, we will develop a next generation of MHD simulations of both star-disk interactions and stellar winds, to model stars over the full range of mass & age, and to characterize how magnetically active stars impact their environments. Simultaneously, we will create a new class of rotational-evolution models that include external torques derived from our simulations, compute the evolution of spin rates of entire star clusters, & compare with observations.
Max ERC Funding
2 206 205 €
Duration
Start date: 2016-07-01, End date: 2022-06-30
Project acronym B Massive
Project Binary massive black hole astrophysics
Researcher (PI) Alberto SESANA
Host Institution (HI) UNIVERSITA' DEGLI STUDI DI MILANO-BICOCCA
Country Italy
Call Details Consolidator Grant (CoG), PE9, ERC-2018-COG
Summary Massive black hole binaries (MBHBs) are the most extreme, fascinating yet elusive astrophysical objects in the Universe. Establishing observationally their existence will be a milestone for contemporary astronomy, providing a fundamental missing piece in the puzzle of galaxy formation, piercing through the (hydro)dynamical physical processes shaping dense galactic nuclei from parsec scales down to the event horizon, and probing gravity in extreme conditions.
We can both see and listen to MBHBs. Remarkably, besides arguably being among the brightest variable objects shining in the Cosmos, MBHBs are also the loudest gravitational wave (GW) sources in the Universe. As such, we shall take advantage of both the type of messengers – photons and gravitons – they are sending to us, which can now be probed by all-sky time-domain surveys and radio pulsar timing arrays (PTAs) respectively.
B MASSIVE leverages on a unique comprehensive approach combining theoretical astrophysics, radio and gravitational-wave astronomy and time-domain surveys, with state of the art data analysis techniques to: i) observationally prove the existence of MBHBs, ii) understand and constrain their astrophysics and dynamics, iii) enable and bring closer in time the direct detection of GWs with PTA.
As European PTA (EPTA) executive committee member and former I
International PTA (IPTA) chair, I am a driving force in the development of pulsar timing science world-wide, and the project will build on the profound knowledge, broad vision and wide collaboration network that established me as a world leader in the field of MBHB and GW astrophysics. B MASSIVE is extremely timely; a pulsar timing data set of unprecedented quality is being assembled by EPTA/IPTA, and Time-Domain astronomy surveys are at their dawn. In the long term, B MASSIVE will be a fundamental milestone establishing European leadership in the cutting-edge field of MBHB astrophysics in the era of LSST, SKA and LISA.
Summary
Massive black hole binaries (MBHBs) are the most extreme, fascinating yet elusive astrophysical objects in the Universe. Establishing observationally their existence will be a milestone for contemporary astronomy, providing a fundamental missing piece in the puzzle of galaxy formation, piercing through the (hydro)dynamical physical processes shaping dense galactic nuclei from parsec scales down to the event horizon, and probing gravity in extreme conditions.
We can both see and listen to MBHBs. Remarkably, besides arguably being among the brightest variable objects shining in the Cosmos, MBHBs are also the loudest gravitational wave (GW) sources in the Universe. As such, we shall take advantage of both the type of messengers – photons and gravitons – they are sending to us, which can now be probed by all-sky time-domain surveys and radio pulsar timing arrays (PTAs) respectively.
B MASSIVE leverages on a unique comprehensive approach combining theoretical astrophysics, radio and gravitational-wave astronomy and time-domain surveys, with state of the art data analysis techniques to: i) observationally prove the existence of MBHBs, ii) understand and constrain their astrophysics and dynamics, iii) enable and bring closer in time the direct detection of GWs with PTA.
As European PTA (EPTA) executive committee member and former I
International PTA (IPTA) chair, I am a driving force in the development of pulsar timing science world-wide, and the project will build on the profound knowledge, broad vision and wide collaboration network that established me as a world leader in the field of MBHB and GW astrophysics. B MASSIVE is extremely timely; a pulsar timing data set of unprecedented quality is being assembled by EPTA/IPTA, and Time-Domain astronomy surveys are at their dawn. In the long term, B MASSIVE will be a fundamental milestone establishing European leadership in the cutting-edge field of MBHB astrophysics in the era of LSST, SKA and LISA.
Max ERC Funding
1 532 750 €
Duration
Start date: 2019-09-01, End date: 2024-08-31