A5049283167- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Neutrino Physics Research
- Quantum Chromodynamics and Particle Interactions
- Astrophysics and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- High-Energy Particle Collisions Research
- Black Holes and Theoretical Physics
- Computational Physics and Python Applications
- Particle Detector Development and Performance
- Cold Atom Physics and Bose-Einstein Condensates
- Radioactive Decay and Measurement Techniques
- Noncommutative and Quantum Gravity Theories
- Scientific Research and Discoveries
- Matrix Theory and Algorithms
- Radio Astronomy Observations and Technology
- Digital Filter Design and Implementation
- Particle Accelerators and Free-Electron Lasers
- Physics of Superconductivity and Magnetism
- Gamma-ray bursts and supernovae
- Superconducting Materials and Applications
- Relativity and Gravitational Theory
- Astronomy and Astrophysical Research
- Cold Fusion and Nuclear Reactions
Université Libre de Bruxelles
2015-2024
European Organization for Nuclear Research
2023
Universidad Autónoma de Madrid
2006-2019
Consejo Superior de Investigaciones Científicas
2019
Instituto de Física Teórica
2012-2019
Institut de Physique Théorique
2008
University of Oxford
2004-2007
Science Oxford
2004
Centre National de la Recherche Scientifique
2001-2003
Centre de Physique Théorique
2001-2003
This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (Search Hidden Particles) experiment is intended to hunt in largely unexplored domain of very weakly interacting particles with masses below Fermi scale, inaccessible LHC experiments, and study tau neutrino physics. same proton beam setup can be used later look decays tau-leptons lepton flavour number non-conservation, $\tau\to 3\mu$ search weakly-interacting sub-GeV dark matter candidates. We discuss...
We consider the possibility that along thermal history of Universe, dark matter (DM) would have been created from Standard Model particles, either through a kinetic mixing portal to an extra U(1) gauge field, or Higgs portal. Depending solely on DM particle mass, and hidden sector interaction, we show how observed relic density can be obtained. There are four possible freeze-in/reannihilation/freeze-out regimes, which together result in simple characteristic phase diagram, with shape...
Matching conditions relate couplings to particle masses. We discuss the importance of one-loop matching in Higgs boson and top quark sector as well choice scale. argue for scales ${\ensuremath{\mu}}_{0,t}\ensuremath{\simeq}{m}_{t}$ ${\ensuremath{\mu}}_{0,H}\ensuremath{\simeq}\mathrm{max}{{m}_{t}{,M}_{H}}$. Using these results, two-loop mass upper bounds are reanalyzed. Previous results $\ensuremath{\Lambda}\ensuremath{\approx}$ few TeV found be too stringent, a recent update is wrong. For...
The mechanism behind Electroweak Symmetry Breaking (EWSB) and the nature of dark matter (DM) are currently among most important issues in high energy physics. Since a natural candidate is weakly interacting massive particle or WIMP, with mass around electroweak scale, it clearly interest to investigate possibility that DM EWSB closely related. In context very simple extension Standard Model, Inert Doublet we show could play crucial role breaking symmetry. this model, lightest component an...
In the WIMP scenario, there is a one-to-one relation between dark matter (DM) relic density and spin-independent direct detection rate if both annihilation of DM its elastic scattering on nuclei go dominantly through Higgs exchange. particular, for masses much smaller than boson mass, ratio relevant cross sections depends only mass. Assuming mass within ranges allowed by recent DAMA collaboration results—taking account channelling effect energy threshold null results other experiments—gives...
Neutrino masses can be generated by fermion triplets with TeV-scale mass, that would manifest at LHC as production of two leptons together heavy standard model (SM) vectors or Higgs, giving rise to final states such $2\ensuremath{\ell}+4j$ (that violate lepton number and/or flavor) $\ensuremath{\ell}+4j+{\mathrm{E\ensuremath{\llap{\not\;}}}}_{T}$. We devise cuts suppress the SM backgrounds these signatures. Furthermore, for most mass range suggested neutrino data, triplet decays are...
Assuming that naturalness should be modified by ignoring quadratic divergences, we propose a simple extension of the Standard Model where weak scale is dynamically generated together with an automatically stable vector. Identifying it as thermal Dark Matter, model has one free parameter. It predicts extra scalar, detectable at colliders, which triggers first-order dark/electroweak cosmological phase transition production gravitational waves. Vacuum stability holds up to Planck scale.
In the context of Self-Interacting Dark Matter as a solution for small-scale structure problems, we consider possibility that could have been produced without being in thermal equilibrium with Standard Model bath. We discuss one by following various dark matter production regimes this kind: freeze-in, reannihilation and freeze-out. exemplify how these mechanisms work particularly simple Hidden Vector model. contrast to scenarios where there is bath, find two which can easily satisfy all...
If dark matter (DM) simply consists in a scalar particle interacting dominantly with the Higgs boson, ratio of its annihilation cross section ---which is relevant both for relic abundance and indirect detection--- spin-independent scattering on nuclei depends only DM mass. It an intriguing result that, fixing mass direct detection rate to fit annual modulation observed by DAMA experiment, one obtains density perfect agreement value. In this short letter we update confront model recent CoGeNT...
Due to their extreme density and low temperature, neutron stars (NS) are efficient probes unveil interactions between standard model dark matter (DM) particles. From elastic scatterings on NS material, DM can get gravitationally trapped by the star. The cooling of through further collisions may lead formation a dense core which could collapse into black hole, thus destroying whole NS. observation old NS, such scenario leads very stringent constraints parameter space asymmetric DM. In this...
A bstract In dimension-less theories of dynamical generation the weak scale, Universe can undergo a period low-scale inflation during which all particles are massless and super-cooling. This leads to new mechanism cosmological Dark Matter relic density: super-cooling easily suppress amount down desired level. is achieved for TeV-scale Matter, if ends when quark condensates form at QCD phase transition. Along this scenario, baryon asymmetry be generated either transition or through...
We consider a question that curiously had not been properly considered thus far: in the standard seesaw model, what is minimum value mass of right-handed (RH) neutrino must have for allowing successful leptogenesis via CP-violating decays? Answering this requires us to take into account number thermal effects. show that, low RH masses, and thanks these effects, turns out proceed efficiently from decay model scalar doublet components lepton. Such decays produce asymmetry at temperatures,...
The focus of this paper lies on the possible experimental tests leptogenesis scenarios. We consider both generated from oscillations, as well out-of-equilibrium decays. As Akhmedov–Rubakov–Smirnov (ARS) mechanism allows for heavy neutrinos in GeV range, opens up a plethora tests, e.g. at neutrino oscillation experiments, neutrinoless double beta decay, and direct searches neutral leptons future facilities. In contrast, testing decays is quite difficult task. comment necessary conditions...
We present a scenario in which remarkably simple relation linking dark matter properties and neutrino masses naturally emerges. This framework points towards low energy theory where the mass originates from existence of light scalar particle keV-MeV range. discuss different ways to constrain test this by means astrophysical cosmological observations as well laboratory experiments. Finally, we point out that one interesting aspect is implied range compatible with required for explanation...
In dark matter (DM) models, the production of a gamma line (or "box-shaped" gamma-ray spectrum) from DM annihilation proceeds in general loop diagram involving heavy charged particle. If particle carries also color charge, this leads inevitably to gluons, with naturally larger rate. We consider scenario which candidates annihilate dominantly into gluon pairs, and determine (as far as possible, model-independent) constraints variety observables: a) relic density, b) anti-protons, c) direct...
Dark matter (DM) may belong to a hidden sector (HS) that is only feebly interacting with the standard model (SM) and have never been in thermal equilibrium early Universe. In this case, observed abundance of dark particles could built up through process known as freeze-in. We show that, for first time, direct detection experiments are testing DM production mechanism. This applies scenarios where SM HS communicate light mediator mass less than few MeV. Through exchange such mediator, very...
We reconsider the model of Minimal Dark Matter (a fermionic, hypercharge-less quintuplet EW interactions) and compute its gamma ray signatures. compare them with a number probes: galactic halo diffuse measurements, center line searches recent dwarf galaxies observations. find that original minimal model, whose mass is fixed at 9.4 TeV by relic abundance requirement, constrained from Galactic Center: it ruled out if Milky Way possesses cuspy profile such as NFW but still allowed has cored...