Project acronym 1st-principles-discs
Project A First Principles Approach to Accretion Discs
Researcher (PI) Martin Elias Pessah
Host Institution (HI) KOBENHAVNS UNIVERSITET
Call Details Starting Grant (StG), PE9, ERC-2012-StG_20111012
Summary Most celestial bodies, from planets, to stars, to black holes; gain mass during their lives by means of an accretion disc. Understanding the physical processes that determine the rate at which matter accretes and energy is radiated in these discs is vital for unraveling the formation, evolution, and fate of almost every type of object in the Universe. Despite the fact that magnetic fields have been known to be crucial in accretion discs since the early 90’s, the majority of astrophysical questions that depend on the details of how disc accretion proceeds are still being addressed using the “standard” accretion disc model (developed in the early 70’s), where magnetic fields do not play an explicit role. This has prevented us from fully exploring the astrophysical consequences and observational signatures of realistic accretion disc models, leading to a profound disconnect between observations (usually interpreted with the standard paradigm) and modern accretion disc theory and numerical simulations (where magnetic turbulence is crucial). The goal of this proposal is to use several complementary approaches in order to finally move beyond the standard paradigm. This program has two main objectives: 1) Develop the theoretical framework to incorporate magnetic fields, and the ensuing turbulence, into self-consistent accretion disc models, and investigate their observational implications. 2) Investigate transport and radiative processes in collision-less disc regions, where non-thermal radiation originates, by employing a kinetic particle description of the plasma. In order to achieve these goals, we will use, and build upon, state-of-the-art magnetohydrodynamic and particle-in-cell codes in conjunction with theoretical modeling. This framework will make it possible to address fundamental questions on stellar and planet formation, binary systems with a compact object, and supermassive black hole feedback in a way that has no counterpart within the standard paradigm.
Summary
Most celestial bodies, from planets, to stars, to black holes; gain mass during their lives by means of an accretion disc. Understanding the physical processes that determine the rate at which matter accretes and energy is radiated in these discs is vital for unraveling the formation, evolution, and fate of almost every type of object in the Universe. Despite the fact that magnetic fields have been known to be crucial in accretion discs since the early 90’s, the majority of astrophysical questions that depend on the details of how disc accretion proceeds are still being addressed using the “standard” accretion disc model (developed in the early 70’s), where magnetic fields do not play an explicit role. This has prevented us from fully exploring the astrophysical consequences and observational signatures of realistic accretion disc models, leading to a profound disconnect between observations (usually interpreted with the standard paradigm) and modern accretion disc theory and numerical simulations (where magnetic turbulence is crucial). The goal of this proposal is to use several complementary approaches in order to finally move beyond the standard paradigm. This program has two main objectives: 1) Develop the theoretical framework to incorporate magnetic fields, and the ensuing turbulence, into self-consistent accretion disc models, and investigate their observational implications. 2) Investigate transport and radiative processes in collision-less disc regions, where non-thermal radiation originates, by employing a kinetic particle description of the plasma. In order to achieve these goals, we will use, and build upon, state-of-the-art magnetohydrodynamic and particle-in-cell codes in conjunction with theoretical modeling. This framework will make it possible to address fundamental questions on stellar and planet formation, binary systems with a compact object, and supermassive black hole feedback in a way that has no counterpart within the standard paradigm.
Max ERC Funding
1 793 697 €
Duration
Start date: 2013-02-01, End date: 2018-01-31
Project acronym 3DICE
Project 3D Interstellar Chemo-physical Evolution
Researcher (PI) Valentine Wakelam
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE9, ERC-2013-StG
Summary At the end of their life, stars spread their inner material into the diffuse interstellar medium. This diffuse medium gets locally denser and form dark clouds (also called dense or molecular clouds) whose innermost part is shielded from the external UV field by the dust, allowing for molecules to grow and get more complex. Gravitational collapse occurs inside these dense clouds, forming protostars and their surrounding disks, and eventually planetary systems like (or unlike) our solar system. The formation and evolution of molecules, minerals, ices and organics from the diffuse medium to planetary bodies, their alteration or preservation throughout this cosmic chemical history set the initial conditions for building planets, atmospheres and possibly the first bricks of life. The current view of interstellar chemistry is based on fragmental works on key steps of the sequence that are observed. The objective of this proposal is to follow the fractionation of the elements between the gas-phase and the interstellar grains, from the most diffuse medium to protoplanetary disks, in order to constrain the chemical composition of the material in which planets are formed. The potential outcome of this project is to get a consistent and more accurate description of the chemical evolution of interstellar matter. To achieve this objective, I will improve our chemical model by adding new processes on grain surfaces relevant under the diffuse medium conditions. This upgraded gas-grain model will be coupled to 3D dynamical models of the formation of dense clouds from diffuse medium and of protoplanetary disks from dense clouds. The computed chemical composition will also be used with 3D radiative transfer codes to study the chemical tracers of the physics of protoplanetary disk formation. The robustness of the model predictions will be studied with sensitivity analyses. Finally, model results will be confronted to observations to address some of the current challenges.
Summary
At the end of their life, stars spread their inner material into the diffuse interstellar medium. This diffuse medium gets locally denser and form dark clouds (also called dense or molecular clouds) whose innermost part is shielded from the external UV field by the dust, allowing for molecules to grow and get more complex. Gravitational collapse occurs inside these dense clouds, forming protostars and their surrounding disks, and eventually planetary systems like (or unlike) our solar system. The formation and evolution of molecules, minerals, ices and organics from the diffuse medium to planetary bodies, their alteration or preservation throughout this cosmic chemical history set the initial conditions for building planets, atmospheres and possibly the first bricks of life. The current view of interstellar chemistry is based on fragmental works on key steps of the sequence that are observed. The objective of this proposal is to follow the fractionation of the elements between the gas-phase and the interstellar grains, from the most diffuse medium to protoplanetary disks, in order to constrain the chemical composition of the material in which planets are formed. The potential outcome of this project is to get a consistent and more accurate description of the chemical evolution of interstellar matter. To achieve this objective, I will improve our chemical model by adding new processes on grain surfaces relevant under the diffuse medium conditions. This upgraded gas-grain model will be coupled to 3D dynamical models of the formation of dense clouds from diffuse medium and of protoplanetary disks from dense clouds. The computed chemical composition will also be used with 3D radiative transfer codes to study the chemical tracers of the physics of protoplanetary disk formation. The robustness of the model predictions will be studied with sensitivity analyses. Finally, model results will be confronted to observations to address some of the current challenges.
Max ERC Funding
1 166 231 €
Duration
Start date: 2013-09-01, End date: 2018-08-31
Project acronym ADULT
Project Analysis of the Dark Universe through Lensing Tomography
Researcher (PI) Hendrik Hoekstra
Host Institution (HI) UNIVERSITEIT LEIDEN
Call Details Starting Grant (StG), PE9, ERC-2011-StG_20101014
Summary The discoveries that the expansion of the universe is accelerating due to an unknown “dark energy”
and that most of the matter is invisible, highlight our lack of understanding of the major constituents
of the universe. These surprising findings set the stage for research in cosmology at the start of the
21st century. The objective of this proposal is to advance observational constraints to a level where we can distinguish between physical mechanisms that aim to explain the properties of dark energy and the observed distribution of dark matter throughout the universe. We use a relatively new technique called weak gravitational lensing: the accurate measurement of correlations in the orientations of distant galaxies enables us to map the dark matter distribution directly and to extract the cosmological information that is encoded by the large-scale structure.
To study the dark universe we will analyse data from a new state-of-the-art imaging survey: the Kilo-
Degree Survey (KiDS) will cover 1500 square degrees in 9 filters. The combination of its large survey
area and the availability of exquisite photometric redshifts for the sources makes KiDS the first
project that can place interesting constraints on the dark energy equation-of-state using lensing data
alone. Combined with complementary results from Planck, our measurements will provide one of the
best views of the dark side of the universe before much larger space-based projects commence.
To reach the desired accuracy we need to carefully measure the shapes of distant background galaxies. We also need to account for any intrinsic alignments that arise due to tidal interactions, rather than through lensing. Reducing these observational and physical biases to negligible levels is a necessarystep to ensure the success of KiDS and an important part of our preparation for more challenging projects such as the European-led space mission Euclid.
Summary
The discoveries that the expansion of the universe is accelerating due to an unknown “dark energy”
and that most of the matter is invisible, highlight our lack of understanding of the major constituents
of the universe. These surprising findings set the stage for research in cosmology at the start of the
21st century. The objective of this proposal is to advance observational constraints to a level where we can distinguish between physical mechanisms that aim to explain the properties of dark energy and the observed distribution of dark matter throughout the universe. We use a relatively new technique called weak gravitational lensing: the accurate measurement of correlations in the orientations of distant galaxies enables us to map the dark matter distribution directly and to extract the cosmological information that is encoded by the large-scale structure.
To study the dark universe we will analyse data from a new state-of-the-art imaging survey: the Kilo-
Degree Survey (KiDS) will cover 1500 square degrees in 9 filters. The combination of its large survey
area and the availability of exquisite photometric redshifts for the sources makes KiDS the first
project that can place interesting constraints on the dark energy equation-of-state using lensing data
alone. Combined with complementary results from Planck, our measurements will provide one of the
best views of the dark side of the universe before much larger space-based projects commence.
To reach the desired accuracy we need to carefully measure the shapes of distant background galaxies. We also need to account for any intrinsic alignments that arise due to tidal interactions, rather than through lensing. Reducing these observational and physical biases to negligible levels is a necessarystep to ensure the success of KiDS and an important part of our preparation for more challenging projects such as the European-led space mission Euclid.
Max ERC Funding
1 316 880 €
Duration
Start date: 2012-01-01, End date: 2016-12-31
Project acronym AIDA
Project An Illumination of the Dark Ages: modeling reionization and interpreting observations
Researcher (PI) Andrei Albert Mesinger
Host Institution (HI) SCUOLA NORMALE SUPERIORE
Call Details Starting Grant (StG), PE9, ERC-2014-STG
Summary "Understanding the dawn of the first galaxies and how their light permeated the early Universe is at the very frontier of modern astrophysical cosmology. Generous resources, including ambitions observational programs, are being devoted to studying these epochs of Cosmic Dawn (CD) and Reionization (EoR). In order to interpret these observations, we propose to build on our widely-used, semi-numeric simulation tool, 21cmFAST, and apply it to observations. Using sub-grid, semi-analytic models, we will incorporate additional physical processes governing the evolution of sources and sinks of ionizing photons. The resulting state-of-the-art simulations will be well poised to interpret topical observations of quasar spectra and the cosmic 21cm signal. They would be both physically-motivated and fast, allowing us to rapidly explore astrophysical parameter space. We will statistically quantify the resulting degeneracies and constraints, providing a robust answer to the question, ""What can we learn from EoR/CD observations?"" As an end goal, these investigations will help us understand when the first generations of galaxies formed, how they drove the EoR, and what are the associated large-scale observational signatures."
Summary
"Understanding the dawn of the first galaxies and how their light permeated the early Universe is at the very frontier of modern astrophysical cosmology. Generous resources, including ambitions observational programs, are being devoted to studying these epochs of Cosmic Dawn (CD) and Reionization (EoR). In order to interpret these observations, we propose to build on our widely-used, semi-numeric simulation tool, 21cmFAST, and apply it to observations. Using sub-grid, semi-analytic models, we will incorporate additional physical processes governing the evolution of sources and sinks of ionizing photons. The resulting state-of-the-art simulations will be well poised to interpret topical observations of quasar spectra and the cosmic 21cm signal. They would be both physically-motivated and fast, allowing us to rapidly explore astrophysical parameter space. We will statistically quantify the resulting degeneracies and constraints, providing a robust answer to the question, ""What can we learn from EoR/CD observations?"" As an end goal, these investigations will help us understand when the first generations of galaxies formed, how they drove the EoR, and what are the associated large-scale observational signatures."
Max ERC Funding
1 468 750 €
Duration
Start date: 2015-05-01, End date: 2021-01-31
Project acronym ANISOTROPIC UNIVERSE
Project The anisotropic universe -- a reality or fluke?
Researcher (PI) Hans Kristian Kamfjord Eriksen
Host Institution (HI) UNIVERSITETET I OSLO
Call Details Starting Grant (StG), PE9, ERC-2010-StG_20091028
Summary "During the last decade, a strikingly successful cosmological concordance model has been established. With only six free parameters, nearly all observables, comprising millions of data points, may be fitted with outstanding precision. However, in this beautiful picture a few ""blemishes"" have turned up, apparently not consistent with the standard model: While the model predicts that the universe is isotropic (i.e., looks the same in all directions) and homogeneous (i.e., the statistical properties are the same everywhere), subtle hints of the contrary are now seen. For instance, peculiar preferred directions and correlations are observed in the cosmic microwave background; some studies considering nearby galaxies suggest the existence of anomalous large-scale cosmic flows; a study of distant quasars hints towards unexpected large-scale correlations. All of these reports are individually highly intriguing, and together they hint toward a more complicated and interesting universe than previously imagined -- but none of the reports can be considered decisive. One major obstacle in many cases has been the relatively poor data quality.
This is currently about to change, as the next generation of new and far more powerful experiments are coming online. Of special interest to me are Planck, an ESA-funded CMB satellite currently taking data; QUIET, a ground-based CMB polarization experiment located in Chile; and various large-scale structure (LSS) data sets, such as the SDSS and 2dF surveys, and in the future Euclid, a proposed galaxy survey satellite also funded by ESA. By combining the world s best data from both CMB and LSS measurements, I will in the proposed project attempt to settle this question: Is our universe really anisotropic? Or are these recent claims only the results of systematic errors or statistical flukes? If the claims turn out to hold against this tide of new and high-quality data, then cosmology as a whole may need to be re-written."
Summary
"During the last decade, a strikingly successful cosmological concordance model has been established. With only six free parameters, nearly all observables, comprising millions of data points, may be fitted with outstanding precision. However, in this beautiful picture a few ""blemishes"" have turned up, apparently not consistent with the standard model: While the model predicts that the universe is isotropic (i.e., looks the same in all directions) and homogeneous (i.e., the statistical properties are the same everywhere), subtle hints of the contrary are now seen. For instance, peculiar preferred directions and correlations are observed in the cosmic microwave background; some studies considering nearby galaxies suggest the existence of anomalous large-scale cosmic flows; a study of distant quasars hints towards unexpected large-scale correlations. All of these reports are individually highly intriguing, and together they hint toward a more complicated and interesting universe than previously imagined -- but none of the reports can be considered decisive. One major obstacle in many cases has been the relatively poor data quality.
This is currently about to change, as the next generation of new and far more powerful experiments are coming online. Of special interest to me are Planck, an ESA-funded CMB satellite currently taking data; QUIET, a ground-based CMB polarization experiment located in Chile; and various large-scale structure (LSS) data sets, such as the SDSS and 2dF surveys, and in the future Euclid, a proposed galaxy survey satellite also funded by ESA. By combining the world s best data from both CMB and LSS measurements, I will in the proposed project attempt to settle this question: Is our universe really anisotropic? Or are these recent claims only the results of systematic errors or statistical flukes? If the claims turn out to hold against this tide of new and high-quality data, then cosmology as a whole may need to be re-written."
Max ERC Funding
1 500 000 €
Duration
Start date: 2011-01-01, End date: 2015-12-31
Project acronym ASTROLAB
Project Cold Collisions and the Pathways Toward Life in Interstellar Space
Researcher (PI) Holger Kreckel
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Starting Grant (StG), PE9, ERC-2012-StG_20111012
Summary Modern telescopes like Herschel and ALMA open up a new window into molecular astrophysics to investigate a surprisingly rich chemistry that operates even at low densities and low temperatures. Observations with these instruments have the potential of unraveling key questions of astrobiology, like the accumulation of water and pre-biotic organic molecules on (exo)planets from asteroids and comets. Hand-in-hand with the heightened observational activities comes a strong demand for a thorough understanding of the molecular formation mechanisms. The vast majority of interstellar molecules are formed in ion-neutral reactions that remain efficient even at low temperatures. Unfortunately, the unusual nature of these processes under terrestrial conditions makes their laboratory study extremely difficult.
To address these issues, I propose to build a versatile merged beams setup for laboratory studies of ion-neutral collisions at the Cryogenic Storage Ring (CSR), the most ambitious of the next-generation storage devices under development worldwide. With this experimental setup, I will make use of a low-temperature and low-density environment that is ideal to simulate the conditions prevailing in interstellar space. The cryogenic surrounding, in combination with laser-generated ground state atom beams, will allow me to perform precise energy-resolved rate coefficient measurements for reactions between cold molecular ions (like, e.g., H2+, H3+, HCO+, CH2+, CH3+, etc.) and neutral atoms (H, D, C or O) in order to shed light on long-standing problems of astrochemistry and the formation of organic molecules in space.
With the large variability of the collision energy (corresponding to 40-40000 K), I will be able to provide data that are crucial for the interpretation of molecular observations in a variety of objects, ranging from cold molecular clouds to warm layers in protoplanetary disks.
Summary
Modern telescopes like Herschel and ALMA open up a new window into molecular astrophysics to investigate a surprisingly rich chemistry that operates even at low densities and low temperatures. Observations with these instruments have the potential of unraveling key questions of astrobiology, like the accumulation of water and pre-biotic organic molecules on (exo)planets from asteroids and comets. Hand-in-hand with the heightened observational activities comes a strong demand for a thorough understanding of the molecular formation mechanisms. The vast majority of interstellar molecules are formed in ion-neutral reactions that remain efficient even at low temperatures. Unfortunately, the unusual nature of these processes under terrestrial conditions makes their laboratory study extremely difficult.
To address these issues, I propose to build a versatile merged beams setup for laboratory studies of ion-neutral collisions at the Cryogenic Storage Ring (CSR), the most ambitious of the next-generation storage devices under development worldwide. With this experimental setup, I will make use of a low-temperature and low-density environment that is ideal to simulate the conditions prevailing in interstellar space. The cryogenic surrounding, in combination with laser-generated ground state atom beams, will allow me to perform precise energy-resolved rate coefficient measurements for reactions between cold molecular ions (like, e.g., H2+, H3+, HCO+, CH2+, CH3+, etc.) and neutral atoms (H, D, C or O) in order to shed light on long-standing problems of astrochemistry and the formation of organic molecules in space.
With the large variability of the collision energy (corresponding to 40-40000 K), I will be able to provide data that are crucial for the interpretation of molecular observations in a variety of objects, ranging from cold molecular clouds to warm layers in protoplanetary disks.
Max ERC Funding
1 486 800 €
Duration
Start date: 2012-09-01, End date: 2017-11-30
Project acronym ATMO
Project Atmospheres across the Universe
Researcher (PI) Pascal TREMBLIN
Host Institution (HI) COMMISSARIAT A L ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
Call Details Starting Grant (StG), PE9, ERC-2017-STG
Summary Which molecules are present in the atmosphere of exoplanets? What are their mass, radius and age? Do they have clouds, convection (atmospheric turbulence), fingering convection, or a circulation induced by irradiation? These questions are fundamental in exoplanetology in order to study issues such as planet formation and exoplanet habitability.
Yet, the impact of fingering convection and circulation induced by irradiation remain poorly understood:
- Fingering convection (triggered by gradients of mean-molecular-weight) has already been suggested to happen in stars (accumulation of heavy elements) and in brown dwarfs and exoplanets (chemical transition e.g. CO/CH4). A large-scale efficient turbulent transport of energy through the fingering instability can reduce the temperature gradient in the atmosphere and explain many observed spectral properties of brown dwarfs and exoplanets. Nonetheless, this large-scale efficiency is not yet characterized and standard approximations (Boussinesq) cannot be used to achieve this goal.
- The interaction between atmospheric circulation and the fingering instability is an open question in the case of irradiated exoplanets. Fingering convection can change the location and magnitude of the hot spot induced by irradiation, whereas the hot deep atmosphere induced by irradiation can change the location of the chemical transitions that trigger the fingering instability.
This project will characterize the impact of fingering convection in the atmosphere of stars, brown dwarfs, and exoplanets and its interaction with the circulation in the case of irradiated planets. By developing innovative numerical models, we will characterize the reduction of the temperature gradient of the atmosphere induced by the instability and study the impact of the circulation. We will then predict and interpret the mass, radius, and chemical composition of exoplanets that will be observed with future missions such as the James Webb Space Telescope (JWST).
Summary
Which molecules are present in the atmosphere of exoplanets? What are their mass, radius and age? Do they have clouds, convection (atmospheric turbulence), fingering convection, or a circulation induced by irradiation? These questions are fundamental in exoplanetology in order to study issues such as planet formation and exoplanet habitability.
Yet, the impact of fingering convection and circulation induced by irradiation remain poorly understood:
- Fingering convection (triggered by gradients of mean-molecular-weight) has already been suggested to happen in stars (accumulation of heavy elements) and in brown dwarfs and exoplanets (chemical transition e.g. CO/CH4). A large-scale efficient turbulent transport of energy through the fingering instability can reduce the temperature gradient in the atmosphere and explain many observed spectral properties of brown dwarfs and exoplanets. Nonetheless, this large-scale efficiency is not yet characterized and standard approximations (Boussinesq) cannot be used to achieve this goal.
- The interaction between atmospheric circulation and the fingering instability is an open question in the case of irradiated exoplanets. Fingering convection can change the location and magnitude of the hot spot induced by irradiation, whereas the hot deep atmosphere induced by irradiation can change the location of the chemical transitions that trigger the fingering instability.
This project will characterize the impact of fingering convection in the atmosphere of stars, brown dwarfs, and exoplanets and its interaction with the circulation in the case of irradiated planets. By developing innovative numerical models, we will characterize the reduction of the temperature gradient of the atmosphere induced by the instability and study the impact of the circulation. We will then predict and interpret the mass, radius, and chemical composition of exoplanets that will be observed with future missions such as the James Webb Space Telescope (JWST).
Max ERC Funding
1 500 000 €
Duration
Start date: 2018-02-01, End date: 2023-01-31
Project acronym BACCO
Project Bias and Clustering Calculations Optimised: Maximising discovery with galaxy surveys
Researcher (PI) Raúl Esteban ANGULO de la Fuente
Host Institution (HI) FUNDACION CENTRO DE ESTUDIOS DE FISICA DEL COSMOS DE ARAGON
Call Details Starting Grant (StG), PE9, ERC-2016-STG
Summary A new generation of galaxy surveys will soon start measuring the spatial distribution of millions of galaxies over a broad range of redshifts, offering an imminent opportunity to discover new physics. A detailed comparison of these measurements with theoretical models of galaxy clustering may reveal a new fundamental particle, a breakdown of General Relativity, or a hint on the nature of cosmic acceleration. Despite a large progress in the analytic treatment of structure formation in recent years, traditional clustering models still suffer from large uncertainties. This limits cosmological analyses to a very restricted range of scales and statistics, which will be one of the main obstacles to reach a comprehensive exploitation of future surveys.
Here I propose to develop a novel simulation--based approach to predict galaxy clustering. Combining recent advances in computational cosmology, from cosmological N--body calculations to physically-motivated galaxy formation models, I will develop a unified framework to directly predict the position and velocity of individual dark matter structures and galaxies as function of cosmological and astrophysical parameters. In this formulation, galaxy clustering will be a prediction of a set of physical assumptions in a given cosmological setting. The new theoretical framework will be flexible, accurate and fast: it will provide predictions for any clustering statistic, down to scales 100 times smaller than in state-of-the-art perturbation--theory--based models, and in less than 1 minute of CPU time. These advances will enable major improvements in future cosmological constraints, which will significantly increase the overall power of future surveys maximising our potential to discover new physics.
Summary
A new generation of galaxy surveys will soon start measuring the spatial distribution of millions of galaxies over a broad range of redshifts, offering an imminent opportunity to discover new physics. A detailed comparison of these measurements with theoretical models of galaxy clustering may reveal a new fundamental particle, a breakdown of General Relativity, or a hint on the nature of cosmic acceleration. Despite a large progress in the analytic treatment of structure formation in recent years, traditional clustering models still suffer from large uncertainties. This limits cosmological analyses to a very restricted range of scales and statistics, which will be one of the main obstacles to reach a comprehensive exploitation of future surveys.
Here I propose to develop a novel simulation--based approach to predict galaxy clustering. Combining recent advances in computational cosmology, from cosmological N--body calculations to physically-motivated galaxy formation models, I will develop a unified framework to directly predict the position and velocity of individual dark matter structures and galaxies as function of cosmological and astrophysical parameters. In this formulation, galaxy clustering will be a prediction of a set of physical assumptions in a given cosmological setting. The new theoretical framework will be flexible, accurate and fast: it will provide predictions for any clustering statistic, down to scales 100 times smaller than in state-of-the-art perturbation--theory--based models, and in less than 1 minute of CPU time. These advances will enable major improvements in future cosmological constraints, which will significantly increase the overall power of future surveys maximising our potential to discover new physics.
Max ERC Funding
1 484 240 €
Duration
Start date: 2017-09-01, End date: 2022-08-31
Project acronym Beacon
Project Beacons in the Dark
Researcher (PI) Paulo César Carvalho Freire
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Starting Grant (StG), PE9, ERC-2011-StG_20101014
Summary BEACON aims at performing an ambitious multi-disciplinary (optical, radio astronomy and theoretical physics) study to enable a fundamentally improved understanding of gravitation and space-time. For almost a century Einstein's general relativity has been the last word on gravity. However, superstring theory predicts new gravitational phenomena beyond relativity. In this proposal I will attempt to detect these new phenomena, with a sensitivity 20 times better than state-of-the-art attempts. A successful detection would take physics beyond its current understanding of the Universe.
These new gravitational phenomena are emission of dipolar gravitational waves and the violation of the strong equivalence principle (SEP). I plan to look for them by timing newly discovered binary pulsars. I will improve upon the best current limits on dipolar gravitational wave emission by a factor of 20 within the time of this proposal. I also plan to develop a test of the Strong Equivalence Principle using a new pulsar/main-sequence star binary. The precision of this test is likely to surpass the current best limits within the time frame of this proposal and then keep improving indefinitely with time. This happens because this is the cleanest gravitational experiment ever carried out.
In order to further these goals, I plan to build the ultimate pulsar observing system. By taking advantage of recent technological advances in microwave engineering (particularly sensitive ultra-wide band receivers) digital electronics (fast analogue-to-digital converters and digital spectrometers) and computing, my team and me will be able to greatly improve the sensitivity and precision for pulsar timing experiments and exploit the capabilities of modern radio telescopes to their limits.
Pulsars are the beacons that will guide me in these new, uncharted seas.
Summary
BEACON aims at performing an ambitious multi-disciplinary (optical, radio astronomy and theoretical physics) study to enable a fundamentally improved understanding of gravitation and space-time. For almost a century Einstein's general relativity has been the last word on gravity. However, superstring theory predicts new gravitational phenomena beyond relativity. In this proposal I will attempt to detect these new phenomena, with a sensitivity 20 times better than state-of-the-art attempts. A successful detection would take physics beyond its current understanding of the Universe.
These new gravitational phenomena are emission of dipolar gravitational waves and the violation of the strong equivalence principle (SEP). I plan to look for them by timing newly discovered binary pulsars. I will improve upon the best current limits on dipolar gravitational wave emission by a factor of 20 within the time of this proposal. I also plan to develop a test of the Strong Equivalence Principle using a new pulsar/main-sequence star binary. The precision of this test is likely to surpass the current best limits within the time frame of this proposal and then keep improving indefinitely with time. This happens because this is the cleanest gravitational experiment ever carried out.
In order to further these goals, I plan to build the ultimate pulsar observing system. By taking advantage of recent technological advances in microwave engineering (particularly sensitive ultra-wide band receivers) digital electronics (fast analogue-to-digital converters and digital spectrometers) and computing, my team and me will be able to greatly improve the sensitivity and precision for pulsar timing experiments and exploit the capabilities of modern radio telescopes to their limits.
Pulsars are the beacons that will guide me in these new, uncharted seas.
Max ERC Funding
1 892 376 €
Duration
Start date: 2011-09-01, End date: 2016-08-31
Project acronym BEBOP
Project Binaries Escorted By Orbiting Planets
Researcher (PI) Amaury TRIAUD
Host Institution (HI) THE UNIVERSITY OF BIRMINGHAM
Call Details Starting Grant (StG), PE9, ERC-2018-STG
Summary Planets orbiting both stars of a binary system -circumbinary planets- are challenging our understanding about how planets assemble, and how their orbits subsequently evolve. Long confined to science-fiction, circumbinary planets were confirmed by the Kepler spacecraft, in one of its most spectacular, and impactful result. Despite Kepler’s insights, a lot remains unknown about these planets. Kepler also suffered from intractable biases that the BEBOP project will solve.
BEBOP will revolutionise how we detect and study circumbinary planets. Conducting a Doppler survey, we will vastly improve the efficiency of circumbinary planet detection, and remove Kepler’s biases. BEBOP will construct a clearer picture of the circumbinary planet population, and free us from the inherent vagaries, and important costs of space-funding. Thanks to the Doppler method we will study dynamical effects unique to circumbinary planets, estimate their multiplicity, and compute their true occurrence rate.
Circumbinary planets are essential objects. Binaries disturbe planet formation. Any similarity, and any difference between the population of circumbinary planets and planets orbiting single stars, will bring novel information about how planets are produced. In addition, circumbinary planets have unique orbital properties that boost their probability to experience transits. BEBOP’s detections will open the door to atmospheric studies of colder worlds than presently available.
Based on already discovered systems, and on two successful proofs-of-concept, the BEBOP team will detect 15 circumbinary gas-giants, three times more than Kepler. BEBOP will provide an unambiguous measure of the efficiency of gas-giant formation in circumbinary environments. In addition the BEBOP project comes with an ambitious programme to combine three detection methods (Doppler, transits, and astrometry) in a holistic approach that will bolster investigations into circumbinary planets, and create a lasting legacy.
Summary
Planets orbiting both stars of a binary system -circumbinary planets- are challenging our understanding about how planets assemble, and how their orbits subsequently evolve. Long confined to science-fiction, circumbinary planets were confirmed by the Kepler spacecraft, in one of its most spectacular, and impactful result. Despite Kepler’s insights, a lot remains unknown about these planets. Kepler also suffered from intractable biases that the BEBOP project will solve.
BEBOP will revolutionise how we detect and study circumbinary planets. Conducting a Doppler survey, we will vastly improve the efficiency of circumbinary planet detection, and remove Kepler’s biases. BEBOP will construct a clearer picture of the circumbinary planet population, and free us from the inherent vagaries, and important costs of space-funding. Thanks to the Doppler method we will study dynamical effects unique to circumbinary planets, estimate their multiplicity, and compute their true occurrence rate.
Circumbinary planets are essential objects. Binaries disturbe planet formation. Any similarity, and any difference between the population of circumbinary planets and planets orbiting single stars, will bring novel information about how planets are produced. In addition, circumbinary planets have unique orbital properties that boost their probability to experience transits. BEBOP’s detections will open the door to atmospheric studies of colder worlds than presently available.
Based on already discovered systems, and on two successful proofs-of-concept, the BEBOP team will detect 15 circumbinary gas-giants, three times more than Kepler. BEBOP will provide an unambiguous measure of the efficiency of gas-giant formation in circumbinary environments. In addition the BEBOP project comes with an ambitious programme to combine three detection methods (Doppler, transits, and astrometry) in a holistic approach that will bolster investigations into circumbinary planets, and create a lasting legacy.
Max ERC Funding
1 186 313 €
Duration
Start date: 2018-11-01, End date: 2023-10-31
