Project acronym ARQADIA
Project Artificial quantum materials with photons: many-body physics and topology
Researcher (PI) Sylvain Ravets
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary Physical systems featuring strong electronic correlations exhibit fascinating phenomena, as exemplified by high-Tc superconductivity, quantum magnetism or fractional quantum Hall physics. Inspired by these effects, new ideas have emerged to harness strongly correlated phases in artificial quantum materials, and use them as a resource for fundamental science and for quantum technology. Promising approaches for producing quantum devices are found in condensed matter platforms: one can indeed benefit from nanofabrication to engineer systems that are compact, versatile, and which can potentially be integrated in large-scale architectures. The main goal of ARQADIA is to engineer and study quantum correlated and topological phases of light using artificial photonic materials that I will fabricate in a solid-state platform. I will use exciton-polaritons in semiconductor microcavities, which are hybrid quasiparticles resulting from strong coupling between cavity photons and quantum well excitons. Polaritons are particularly attractive since they combine the best of two worlds: (i) through their photon component, they can be confined in microstrucutres and manipulated using optical spectroscopy; (ii) through their matter component, interactions between polaritons can be tuned and reinforced. Moreover, polaritons can be detected through the decay of cavity photons, which means that they naturally implement out-of-equilibrium physics and allow addressing fascinating questions related to the interplay between quantum correlations and dissipation. Within ARQADIA, I will tackle the challenge of engineering quantum correlations between polaritons via a technological breakthrough: I will insert active materials featuring strongly interacting excitons in microcavity lattices. I will use these materials to study out-of-equilibrium strongly correlated phases in vastly different regimes: from 1D to 2D, from weakly to strongly interacting and from topologically trivial to non-trivial.
Summary
Physical systems featuring strong electronic correlations exhibit fascinating phenomena, as exemplified by high-Tc superconductivity, quantum magnetism or fractional quantum Hall physics. Inspired by these effects, new ideas have emerged to harness strongly correlated phases in artificial quantum materials, and use them as a resource for fundamental science and for quantum technology. Promising approaches for producing quantum devices are found in condensed matter platforms: one can indeed benefit from nanofabrication to engineer systems that are compact, versatile, and which can potentially be integrated in large-scale architectures. The main goal of ARQADIA is to engineer and study quantum correlated and topological phases of light using artificial photonic materials that I will fabricate in a solid-state platform. I will use exciton-polaritons in semiconductor microcavities, which are hybrid quasiparticles resulting from strong coupling between cavity photons and quantum well excitons. Polaritons are particularly attractive since they combine the best of two worlds: (i) through their photon component, they can be confined in microstrucutres and manipulated using optical spectroscopy; (ii) through their matter component, interactions between polaritons can be tuned and reinforced. Moreover, polaritons can be detected through the decay of cavity photons, which means that they naturally implement out-of-equilibrium physics and allow addressing fascinating questions related to the interplay between quantum correlations and dissipation. Within ARQADIA, I will tackle the challenge of engineering quantum correlations between polaritons via a technological breakthrough: I will insert active materials featuring strongly interacting excitons in microcavity lattices. I will use these materials to study out-of-equilibrium strongly correlated phases in vastly different regimes: from 1D to 2D, from weakly to strongly interacting and from topologically trivial to non-trivial.
Max ERC Funding
1 499 603 €
Duration
Start date: 2021-01-01, End date: 2025-12-31
Project acronym AxionDM
Project Searching for axion and axion-like-particle dark matter in the laboratory and with high-energy astrophysical observations
Researcher (PI) Manuel Meyer
Host Institution (HI) UNIVERSITAET HAMBURG
Country Germany
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary The nature of dark matter, which makes up more than 80% of the Universe's matter content, remains unknown. Light axions and axion-like particles (ALPs) are well motivated dark-matter candidates that could be detected through their oscillations into photons in the presence of magnetic fields. Here, complementary laboratory and astrophysical searches for dark-matter axions and ALPs are proposed that will cover more than 10 orders of magnitude of possible axion and ALP masses.
The astrophysical searches will focus on high-energy gamma-ray observations with the Fermi Large Area Telescope as well as current and future imaging air Cherenkov telescopes. Photon-ALP oscillations would cause features in the spectra of distant galaxies as well as gamma-ray bursts from core-collapse supernovae. Axion and ALP decay would also increase the opacity of the Universe for gamma rays. These signals will be searched for through novel comparisons of gamma-ray data and model predictions.
The laboratory searches will focus on contributions to the Any Light Particle Search (ALPS II) and International Axion Observatory (IAXO) experiments. New analysis and simulation frameworks, as well as trigger concepts, will be developed in order to significantly improve the background rejection for the Transition Edge Sensor (TES) detector employed in the ALPS experiment. These improvements could pave the way for an ALP detection in the laboratory with first data runs at the ALPS II experiment planned in 2021. Monte Carlo simulations will be used to assess whether TES detectors can achieve the low background rates required for IAXO. Such high energy resolution detectors could help to precisely measure the axion/ALP mass through mass-dependent spectral features.
Through an unprecedented investigation of axion and ALP signatures and by enhancing the sensitivity of future laboratory experiments, the proposed research will discover or rule out so-far unprobed dark-matter axions and ALPs.
Summary
The nature of dark matter, which makes up more than 80% of the Universe's matter content, remains unknown. Light axions and axion-like particles (ALPs) are well motivated dark-matter candidates that could be detected through their oscillations into photons in the presence of magnetic fields. Here, complementary laboratory and astrophysical searches for dark-matter axions and ALPs are proposed that will cover more than 10 orders of magnitude of possible axion and ALP masses.
The astrophysical searches will focus on high-energy gamma-ray observations with the Fermi Large Area Telescope as well as current and future imaging air Cherenkov telescopes. Photon-ALP oscillations would cause features in the spectra of distant galaxies as well as gamma-ray bursts from core-collapse supernovae. Axion and ALP decay would also increase the opacity of the Universe for gamma rays. These signals will be searched for through novel comparisons of gamma-ray data and model predictions.
The laboratory searches will focus on contributions to the Any Light Particle Search (ALPS II) and International Axion Observatory (IAXO) experiments. New analysis and simulation frameworks, as well as trigger concepts, will be developed in order to significantly improve the background rejection for the Transition Edge Sensor (TES) detector employed in the ALPS experiment. These improvements could pave the way for an ALP detection in the laboratory with first data runs at the ALPS II experiment planned in 2021. Monte Carlo simulations will be used to assess whether TES detectors can achieve the low background rates required for IAXO. Such high energy resolution detectors could help to precisely measure the axion/ALP mass through mass-dependent spectral features.
Through an unprecedented investigation of axion and ALP signatures and by enhancing the sensitivity of future laboratory experiments, the proposed research will discover or rule out so-far unprobed dark-matter axions and ALPs.
Max ERC Funding
1 440 763 €
Duration
Start date: 2021-06-01, End date: 2026-05-31
Project acronym BEC-NETWORKS
Project Networks of coupled photon Bose-Einstein condensates: when condensation becomes a computation
Researcher (PI) Jan KLAERS
Host Institution (HI) UNIVERSITEIT TWENTE
Country Netherlands
Call Details Consolidator Grant (CoG), PE2, ERC-2020-COG
Summary Despite large advances in both algorithms and computer technology, even typical instances of computationally hard problems are too difficult to be solved on today’s computers. Unconventional computational devices that break with the usual paradigms of digital electronic computers can help to overcome these limitations. In this project, a network of coupled photon Bose-Einstein condensates will be developed and used as experimental platform to perform ultrafast simulations of classical spin systems. Specifically, the network will be capable of solving the ground-state problem in spin glasses (disordered magnets). The latter constitutes a well-known combinatorial problem that can be mapped mathematically to many other computationally hard problems in machine learning, logistics, computer chip design and DNA sequencing. In a proof-of-principle experiment, I aim to demonstrate that the proposed spin glass simulator performs this computationally hard optimisation problem significantly faster than any other computer today. I have pioneered the Bose-Einstein condensation of photons in optical microcavities, which has enabled us to investigate this genuine quantum-mechanical effect with all-optical methods. In a recent work of my group, we experimentally demonstrate controllable phase relations between photon Bose-Einstein condensates in an optical microcavity. The investigated device realises an optical analogue of a Josephson junction. Similar to a transistor for electronics, a controllable photonic Josephson junction represents the key component for ultrafast optical spin glass simulation and, thus, is the crucial basis for the proposed project. The BEC-NETWORKS project will be the main research project of my research group at the University of Twente.
Summary
Despite large advances in both algorithms and computer technology, even typical instances of computationally hard problems are too difficult to be solved on today’s computers. Unconventional computational devices that break with the usual paradigms of digital electronic computers can help to overcome these limitations. In this project, a network of coupled photon Bose-Einstein condensates will be developed and used as experimental platform to perform ultrafast simulations of classical spin systems. Specifically, the network will be capable of solving the ground-state problem in spin glasses (disordered magnets). The latter constitutes a well-known combinatorial problem that can be mapped mathematically to many other computationally hard problems in machine learning, logistics, computer chip design and DNA sequencing. In a proof-of-principle experiment, I aim to demonstrate that the proposed spin glass simulator performs this computationally hard optimisation problem significantly faster than any other computer today. I have pioneered the Bose-Einstein condensation of photons in optical microcavities, which has enabled us to investigate this genuine quantum-mechanical effect with all-optical methods. In a recent work of my group, we experimentally demonstrate controllable phase relations between photon Bose-Einstein condensates in an optical microcavity. The investigated device realises an optical analogue of a Josephson junction. Similar to a transistor for electronics, a controllable photonic Josephson junction represents the key component for ultrafast optical spin glass simulation and, thus, is the crucial basis for the proposed project. The BEC-NETWORKS project will be the main research project of my research group at the University of Twente.
Max ERC Funding
2 000 000 €
Duration
Start date: 2021-02-01, End date: 2026-01-31
Project acronym BoostDiscovery
Project Boosting the discovery using τs in the ATLAS detector at the Large Hadron Collider
Researcher (PI) Liron Barak
Host Institution (HI) TEL AVIV UNIVERSITY
Country Israel
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary Almost ten years into the highly successful program both in ATLAS and CMS, our understanding of the Standard Model (SM) of particle physics has deepened. Nonetheless, what lies beyond the SM remains one of the most urgent questions of physics in the 21st century. To move forward, one must think outside of the box and leap into uncharted waters. Searches today are aiming at the high-energy frontier, while low-mass resonances are mostly overlooked by the Large Hadron Collider (LHC). Consequently, far-reaching hints of new physics may silentlyhide in the data. Motivated by numerous New Physics (NP) scenarios that often predict light states, such as extended Higgs sectors, axion physics, or dark sector models, among others, the PI will develop new techniques to search for low-mass resonances decaying into two collimated low-pT hadronic τ leptons. τs, being the heaviest, third-generation leptons, provide a unique experimental opportunity to search for low-lying states that would otherwise go undetected. In particular, novel methods to identify boosted hadronic τ+τ− pairs will be established. These techniques will then be used to pave a new path towards discovery of low-mass resonances produced through various production modes. As part of this proposal, the PI will also develop new trigger-level capabilities to further extend the reach of this program at Run-3. As a former leader of the ATLAS Beyond the Standard Model physics group, and current leader of low-mass resonance searches, the PI is ideally positioned to establish a strong research team and take this project to completion, laying the groundwork for the discovery of new physics beyond the SM.
Summary
Almost ten years into the highly successful program both in ATLAS and CMS, our understanding of the Standard Model (SM) of particle physics has deepened. Nonetheless, what lies beyond the SM remains one of the most urgent questions of physics in the 21st century. To move forward, one must think outside of the box and leap into uncharted waters. Searches today are aiming at the high-energy frontier, while low-mass resonances are mostly overlooked by the Large Hadron Collider (LHC). Consequently, far-reaching hints of new physics may silentlyhide in the data. Motivated by numerous New Physics (NP) scenarios that often predict light states, such as extended Higgs sectors, axion physics, or dark sector models, among others, the PI will develop new techniques to search for low-mass resonances decaying into two collimated low-pT hadronic τ leptons. τs, being the heaviest, third-generation leptons, provide a unique experimental opportunity to search for low-lying states that would otherwise go undetected. In particular, novel methods to identify boosted hadronic τ+τ− pairs will be established. These techniques will then be used to pave a new path towards discovery of low-mass resonances produced through various production modes. As part of this proposal, the PI will also develop new trigger-level capabilities to further extend the reach of this program at Run-3. As a former leader of the ATLAS Beyond the Standard Model physics group, and current leader of low-mass resonance searches, the PI is ideally positioned to establish a strong research team and take this project to completion, laying the groundwork for the discovery of new physics beyond the SM.
Max ERC Funding
1 420 000 €
Duration
Start date: 2021-01-01, End date: 2025-12-31
Project acronym COLORFREE
Project High-Precision Global Analysis of Color-Free LHC Processes at Small Recoil
Researcher (PI) Frank Tackmann
Host Institution (HI) STIFTUNG DEUTSCHES ELEKTRONEN-SYNCHROTRON DESY
Country Germany
Call Details Consolidator Grant (CoG), PE2, ERC-2020-COG
Summary The Large Hadron Collider (LHC) at CERN collides protons at the highest energies. With the large datasets from Run 2 and the further increase expected from Run 3, the precision of LHC measurements will significantly improve over the next years. Color-free processes (for which the final state of the hard interaction is color neutral) are of central importance to several high-priority areas of the LHC precision physics program. Prominent examples are measurements of the W-boson mass, of the couplings of the Higgs boson, and searches for the elusive dark matter particles.
The key innovation of COLORFREE will be to combine many different color-free processes in a new type of global analysis in which the dominant theory uncertainties are either eliminated or constrained by the data itself, thereby improving the theoretical precision up to an order of magnitude to the 1-2% level. In doing so, COLORFREE will unlock the full potential of existing and future precision measurements of color-free processes.
This will be achieved 1) by exploiting and further developing a groundbreaking new method to reliably quantify perturbative theory uncertainties and their correlations, which was recently developed by the PI, and 2) by developing innovative new effective-field theory methods to account for all effects that are relevant at this precision but have been neglected so far.
Important outcomes of COLORFREE will be:
1) Determinations of fundamental parameters at the highest possible precision, and stringent tests for possible effects beyond the Standard Model.
2) A new type of precision theory predictions with built-in uncertainties and correlations, which will solve a long-standing problem at the interface of theory and experiment. In particular, precision measurements often avoid theory limitations by relying on theory uncertainties to cancel between different control and signal regions, but until now have had no means to reliably quantify the remaining theory uncertainties.
Summary
The Large Hadron Collider (LHC) at CERN collides protons at the highest energies. With the large datasets from Run 2 and the further increase expected from Run 3, the precision of LHC measurements will significantly improve over the next years. Color-free processes (for which the final state of the hard interaction is color neutral) are of central importance to several high-priority areas of the LHC precision physics program. Prominent examples are measurements of the W-boson mass, of the couplings of the Higgs boson, and searches for the elusive dark matter particles.
The key innovation of COLORFREE will be to combine many different color-free processes in a new type of global analysis in which the dominant theory uncertainties are either eliminated or constrained by the data itself, thereby improving the theoretical precision up to an order of magnitude to the 1-2% level. In doing so, COLORFREE will unlock the full potential of existing and future precision measurements of color-free processes.
This will be achieved 1) by exploiting and further developing a groundbreaking new method to reliably quantify perturbative theory uncertainties and their correlations, which was recently developed by the PI, and 2) by developing innovative new effective-field theory methods to account for all effects that are relevant at this precision but have been neglected so far.
Important outcomes of COLORFREE will be:
1) Determinations of fundamental parameters at the highest possible precision, and stringent tests for possible effects beyond the Standard Model.
2) A new type of precision theory predictions with built-in uncertainties and correlations, which will solve a long-standing problem at the interface of theory and experiment. In particular, precision measurements often avoid theory limitations by relying on theory uncertainties to cancel between different control and signal regions, but until now have had no means to reliably quantify the remaining theory uncertainties.
Max ERC Funding
2 000 000 €
Duration
Start date: 2021-10-01, End date: 2026-09-30
Project acronym CoMoFun
Project Cold Molecules for Fundamental Physics
Researcher (PI) Stefan Truppe
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Country Germany
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary Laser cooling of atomic gases in a magneto-optical trap (MOT) has revolutionized modern physics. A MOT uses precisely tuned lasers and a magnetic field to cool atoms and trap them. It has enabled the invention of precise instruments, such as atomic clocks, magnetometers, gravimeters and accelerometers. It has also enabled new fundamental research with unprecedented precision and the study of matter dominated by quantum effects. However, there is still potential to push the boundaries of science and technology: using ultracold molecules. Project CoMoFun aims to do just this, creating a high-density ultracold gas of polar molecules by laser cooling to build a new platform for fundamental research.
A high-density ultracold gas of polar molecules has a wide range of new applications. It can be used to study a dipolar quantum gas, to test fundamental physics and to store and process quantum information efficiently. An array of polar molecules, all interacting with each other via controllable and strong interactions, can serve as a universal simulator for more complex quantum systems that cannot be modeled by a computer. Simulating such strongly-interacting many-body systems from the bottom-up will aid the understanding of fascinating phenomena such as high-temperature superconductivity and exotic forms of magnetism.
Recently, it has become possible to make a MOT of molecules. However, the density of the molecules is far too low for most applications. CoMoFun will increase the density by five orders of magnitude by laser-cooling stable and deeply-bound aluminum monofluoride molecules. The high density provides an excellent starting point to investigate evaporative cooling to quantum degeneracy. The molecules can then be arranged in a regular array by loading them into a trap formed by interfering laser beams. This instrument can then be used for precision measurements and applications in quantum information and simulation, to realize the full potential of molecular MOT.
Summary
Laser cooling of atomic gases in a magneto-optical trap (MOT) has revolutionized modern physics. A MOT uses precisely tuned lasers and a magnetic field to cool atoms and trap them. It has enabled the invention of precise instruments, such as atomic clocks, magnetometers, gravimeters and accelerometers. It has also enabled new fundamental research with unprecedented precision and the study of matter dominated by quantum effects. However, there is still potential to push the boundaries of science and technology: using ultracold molecules. Project CoMoFun aims to do just this, creating a high-density ultracold gas of polar molecules by laser cooling to build a new platform for fundamental research.
A high-density ultracold gas of polar molecules has a wide range of new applications. It can be used to study a dipolar quantum gas, to test fundamental physics and to store and process quantum information efficiently. An array of polar molecules, all interacting with each other via controllable and strong interactions, can serve as a universal simulator for more complex quantum systems that cannot be modeled by a computer. Simulating such strongly-interacting many-body systems from the bottom-up will aid the understanding of fascinating phenomena such as high-temperature superconductivity and exotic forms of magnetism.
Recently, it has become possible to make a MOT of molecules. However, the density of the molecules is far too low for most applications. CoMoFun will increase the density by five orders of magnitude by laser-cooling stable and deeply-bound aluminum monofluoride molecules. The high density provides an excellent starting point to investigate evaporative cooling to quantum degeneracy. The molecules can then be arranged in a regular array by loading them into a trap formed by interfering laser beams. This instrument can then be used for precision measurements and applications in quantum information and simulation, to realize the full potential of molecular MOT.
Max ERC Funding
1 875 750 €
Duration
Start date: 2021-05-01, End date: 2026-04-30
Project acronym CosmicAntiNuclei
Project Constraining cosmic antinuclei fluxes for indirect dark matter searches with precision measurements of rare antimatter cluster formation
Researcher (PI) Francesca Bellini
Host Institution (HI) ALMA MATER STUDIORUM - UNIVERSITA DI BOLOGNA
Country Italy
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary Visible matter constitutes only 5% of the matter-energy content of the Universe, whereas the remaining 95% is constituted by unknown forms of matter (20%) and energy (75%) that appear as ``dark'' to us. In the landscape of Dark Matter searches, antinuclei are a promising, almost background-free smoking gun signal for WIMPs and are a target of indirect dark matter searches.
This project attacks in a systematic and comprehensive way the modelling of light antimatter cluster formation, necessary to predict the expected signal and background rates for dark matter antinuclei searches in space-borne experiments.
The programme is based on precision measurements of rare antihelium production in proton-proton, proton-nucleus and nucleus-nucleus collisions with the ALICE detector at the CERN LHC.
An innovative approach based on the measurement of two-particle correlations will be applied for the first time to investigate experimentally antinuclei formation via coalescence in relation to the nucleus wavefunction and interaction potential. The results of the analysis of the ALICE data will be input for the modelling of antinuclei formation and propagation in the Galaxy. The final goal of the project is to obtain a prediction for the expected cosmic ray antihelium background rate for AMS-02, further enhancing the scientific value of the proposed research programme.
The outcome of this project will shed light on the production mechanisms of light nuclei and antinuclei in high-energy interactions. In addition, it will extend the ALICE and LHC physics programme to the astrophysical domain, with a deep innovative impact in a well-established field of research. It will have direct fundamental applications to indirect dark matter searches with existing (AMS-02) and future (GAPS, AMS-100) experiments, providing relevant input to frontier research in this sector.
Summary
Visible matter constitutes only 5% of the matter-energy content of the Universe, whereas the remaining 95% is constituted by unknown forms of matter (20%) and energy (75%) that appear as ``dark'' to us. In the landscape of Dark Matter searches, antinuclei are a promising, almost background-free smoking gun signal for WIMPs and are a target of indirect dark matter searches.
This project attacks in a systematic and comprehensive way the modelling of light antimatter cluster formation, necessary to predict the expected signal and background rates for dark matter antinuclei searches in space-borne experiments.
The programme is based on precision measurements of rare antihelium production in proton-proton, proton-nucleus and nucleus-nucleus collisions with the ALICE detector at the CERN LHC.
An innovative approach based on the measurement of two-particle correlations will be applied for the first time to investigate experimentally antinuclei formation via coalescence in relation to the nucleus wavefunction and interaction potential. The results of the analysis of the ALICE data will be input for the modelling of antinuclei formation and propagation in the Galaxy. The final goal of the project is to obtain a prediction for the expected cosmic ray antihelium background rate for AMS-02, further enhancing the scientific value of the proposed research programme.
The outcome of this project will shed light on the production mechanisms of light nuclei and antinuclei in high-energy interactions. In addition, it will extend the ALICE and LHC physics programme to the astrophysical domain, with a deep innovative impact in a well-established field of research. It will have direct fundamental applications to indirect dark matter searches with existing (AMS-02) and future (GAPS, AMS-100) experiments, providing relevant input to frontier research in this sector.
Max ERC Funding
1 468 625 €
Duration
Start date: 2021-07-01, End date: 2026-06-30
Project acronym CosmoChart
Project Charting the multi-TeV cosmos: long-range interactions in dark matter and baryogenesis
Researcher (PI) Kalliopi PETRAKI
Host Institution (HI) SORBONNE UNIVERSITE
Country France
Call Details Consolidator Grant (CoG), PE2, ERC-2020-COG
Summary The origin of the matter-antimatter asymmetry of the universe and the nature of dark matter are among the most fundamental and challenging questions in physics. Their undeniable importance has placed them in the forefront of the experimental and theoretical research in particle physics, cosmology and astrophysics. Our experimental probes are now at the outset of exploring the multi-TeV energy scale. To fully exploit the experimental effort, to design effective search strategies and correctly interpret the experimental results, we must develop reliable theoretical understanding of the plausible dynamics at this scale.
The TeV scale is a new threshold. In this regime, the interactions hypothesised in a variety of well-motivated theories manifest as long-range. This is true for the most widely studied particle-physics scenario for dark matter, particles coupled to the Weak interactions of the Standard Model, as well as many other models. Moreover, many theories of matter-antimatter asymmetry generation invoke heavy particles that couple to lighter force mediators.
Long-range interactions imply very different dynamics than the contact-type interactions most commonly considered in the past. They give rise to non-perturbative effects, with the most prominent being the existence of bound states. Such effects can change the experimental signatures very significantly. CosmoChart will comprehensively investigate the implications of long-range interactions along two directions:
I. The dark matter thermal decoupling in the early universe and indirect detection.
II. The particle-antiparticle asymmetry generation and washout.
The results will have implications for most experimental probes. As the long-range dynamics becomes increasingly more important at higher scales, the investigations of CosmoChart will chart particle cosmology at the TeV scale and beyond.
Summary
The origin of the matter-antimatter asymmetry of the universe and the nature of dark matter are among the most fundamental and challenging questions in physics. Their undeniable importance has placed them in the forefront of the experimental and theoretical research in particle physics, cosmology and astrophysics. Our experimental probes are now at the outset of exploring the multi-TeV energy scale. To fully exploit the experimental effort, to design effective search strategies and correctly interpret the experimental results, we must develop reliable theoretical understanding of the plausible dynamics at this scale.
The TeV scale is a new threshold. In this regime, the interactions hypothesised in a variety of well-motivated theories manifest as long-range. This is true for the most widely studied particle-physics scenario for dark matter, particles coupled to the Weak interactions of the Standard Model, as well as many other models. Moreover, many theories of matter-antimatter asymmetry generation invoke heavy particles that couple to lighter force mediators.
Long-range interactions imply very different dynamics than the contact-type interactions most commonly considered in the past. They give rise to non-perturbative effects, with the most prominent being the existence of bound states. Such effects can change the experimental signatures very significantly. CosmoChart will comprehensively investigate the implications of long-range interactions along two directions:
I. The dark matter thermal decoupling in the early universe and indirect detection.
II. The particle-antiparticle asymmetry generation and washout.
The results will have implications for most experimental probes. As the long-range dynamics becomes increasingly more important at higher scales, the investigations of CosmoChart will chart particle cosmology at the TeV scale and beyond.
Max ERC Funding
1 998 437 €
Duration
Start date: 2021-09-01, End date: 2026-08-31
Project acronym DISCOVERHEP
Project Turning noise into data: a discovery strategy for new weakly-interacting physics
Researcher (PI) Steven Schramm
Host Institution (HI) UNIVERSITE DE GENEVE
Country Switzerland
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary "The ATLAS and CMS Experiments at the Large Hadron Collider (LHC) have done an excellent job in searching for new high-energy physics, pushing out to energy scales which have never before been studied. In contrast, low-energy physics has only been studied in specific contexts at the LHC, and remains largely uncovered in the search for new physics. Despite the main focus being on the high-energy regime, it is entirely possible that new physics is instead hiding in the low-energy regime, and it was not observed in previous collider physics experiments due to being rarely produced.
In the context of the DISCOVERHEP project, I will lead a group in the search for new physics in the largely-uncovered low-energy regime. The project will exploit the very-high LHC beam intensity to turn ""noise"", in the form of traditionally unwanted and ignored additional simultaneous proton-proton collisions, into a currently-untapped wealth of useful low-energy physics data. This novel approach thereby opens up the possibility of conducting high-sensitivity searches for low-energy physics at the LHC.
This massive low-energy physics dataset will be used to enable the project goals, in the form of searches for new low-energy weakly-interacting physics conducted using the ATLAS Detector. Three different search strategies, sensitive to different types of new physics, are considered: two types of direct searches for new light particles such as potential mediators between the Standard Model and Dark Matter, and one generic search for new low-energy physics using anomaly detection techniques. These searches will dramatically extend the sensitivity of ATLAS to new low-energy physics, thus expanding the ATLAS physics program and potentially leading the way towards new discoveries."
Summary
"The ATLAS and CMS Experiments at the Large Hadron Collider (LHC) have done an excellent job in searching for new high-energy physics, pushing out to energy scales which have never before been studied. In contrast, low-energy physics has only been studied in specific contexts at the LHC, and remains largely uncovered in the search for new physics. Despite the main focus being on the high-energy regime, it is entirely possible that new physics is instead hiding in the low-energy regime, and it was not observed in previous collider physics experiments due to being rarely produced.
In the context of the DISCOVERHEP project, I will lead a group in the search for new physics in the largely-uncovered low-energy regime. The project will exploit the very-high LHC beam intensity to turn ""noise"", in the form of traditionally unwanted and ignored additional simultaneous proton-proton collisions, into a currently-untapped wealth of useful low-energy physics data. This novel approach thereby opens up the possibility of conducting high-sensitivity searches for low-energy physics at the LHC.
This massive low-energy physics dataset will be used to enable the project goals, in the form of searches for new low-energy weakly-interacting physics conducted using the ATLAS Detector. Three different search strategies, sensitive to different types of new physics, are considered: two types of direct searches for new light particles such as potential mediators between the Standard Model and Dark Matter, and one generic search for new low-energy physics using anomaly detection techniques. These searches will dramatically extend the sensitivity of ATLAS to new low-energy physics, thus expanding the ATLAS physics program and potentially leading the way towards new discoveries."
Max ERC Funding
1 499 975 €
Duration
Start date: 2021-04-01, End date: 2026-03-31
Project acronym EFT4NP
Project Probing New Physics at the Large Hadron Collider: the Effective Field Theory Pathway
Researcher (PI) Eleni VRYONIDOU
Host Institution (HI) THE UNIVERSITY OF MANCHESTER
Country United Kingdom
Call Details Starting Grant (StG), PE2, ERC-2020-STG
Summary The Large Hadron Collider (LHC) is hunting for signs of New Physics (NP) in the vast amount of data collected by its experiments. If new states are heavier than the collider energy reach, their presence can be revealed by modifications of the interactions of the known particles. The Standard Model Effective Field Theory (SMEFT) parametrises such deviations from the SM, extending the sensitivity to scales beyond those directly probed at colliders. Determining the parameters of the EFT will shed light on the nature of NP and will provide hints to the most important questions in particle physics, such as the shape of the Higgs potential, its relation to electroweak baryogenesis and the amount of CP-violation and its connection to the matter-anti-matter asymmetry. A dedicated campaign of measurements and their SMEFT interpretation is a major goal of the LHC and requires coordination between experimentalists and theorists.
I aim at making essential beyond the state-of-the-art theoretical contributions to the LHC SMEFT programme by:
1) Providing the first fully generic next-to-leading order QCD and electroweak Monte Carlo implementation of SMEFT operators, to allow theorists and experimentalists to perform realistic simulations.
2) Combining accurate SMEFT predictions with LHC data to constrain the operators through a novel robust global determination. The findings, particularly if different from the SM expectations, will point to the scale and nature of NP.
3) Exploring new challenging proposals, such as i) the impact of operator running and mixing and ii) the optimisation of ways of extracting the Higgs self-coupling and probing CP-violation at the LHC, two topics with profound implications for our theoretical understanding of particle physics.
The proposal plays to a key strength of my research expertise and my research record uniquely positions me to successfully lead this ambitious project, which is vital to exploit the full LHC potential.
Summary
The Large Hadron Collider (LHC) is hunting for signs of New Physics (NP) in the vast amount of data collected by its experiments. If new states are heavier than the collider energy reach, their presence can be revealed by modifications of the interactions of the known particles. The Standard Model Effective Field Theory (SMEFT) parametrises such deviations from the SM, extending the sensitivity to scales beyond those directly probed at colliders. Determining the parameters of the EFT will shed light on the nature of NP and will provide hints to the most important questions in particle physics, such as the shape of the Higgs potential, its relation to electroweak baryogenesis and the amount of CP-violation and its connection to the matter-anti-matter asymmetry. A dedicated campaign of measurements and their SMEFT interpretation is a major goal of the LHC and requires coordination between experimentalists and theorists.
I aim at making essential beyond the state-of-the-art theoretical contributions to the LHC SMEFT programme by:
1) Providing the first fully generic next-to-leading order QCD and electroweak Monte Carlo implementation of SMEFT operators, to allow theorists and experimentalists to perform realistic simulations.
2) Combining accurate SMEFT predictions with LHC data to constrain the operators through a novel robust global determination. The findings, particularly if different from the SM expectations, will point to the scale and nature of NP.
3) Exploring new challenging proposals, such as i) the impact of operator running and mixing and ii) the optimisation of ways of extracting the Higgs self-coupling and probing CP-violation at the LHC, two topics with profound implications for our theoretical understanding of particle physics.
The proposal plays to a key strength of my research expertise and my research record uniquely positions me to successfully lead this ambitious project, which is vital to exploit the full LHC potential.
Max ERC Funding
1 407 726 €
Duration
Start date: 2022-01-01, End date: 2026-12-31
