Présidents de session
Parallel Session 1: Dark Matter
- Lucien Heurtier
Parallel Session 1: Dark Matter
- Mathias Pierre
Parallel Session 1: Dark Matter
- Seung J. Lee
Parallel Session 1: Dark Matter
- Donald Kpatcha
Parallel Session 1: Dark Matter
- Alexander Kusenko
Parallel Session 1: Dark Matter
- Giorgio Arcadi
We study scenarios where Dark Matter is a weakly interacting particle (WIMP) embedded in an ElectroWeak (EW) multiplet. In particular, we consider both real SU(2) representations with hypercharge Y = 0, that automatically avoid direct detection constraints from tree-level Z-exchange, and complex ones with Y ̸= 0. In the latter case, the minimal inelastic splitting between the DM and its EW...
Supersymmetric twin Higgs models have a discrete symmetry for which each standard model particle and its supersymmetric partner have a corresponding state that transforms under a mirror standard model gauge group. This framework is able to accommodate the nondiscovery of new particles at the LHC with the naturalness of the electroweak scale. I will show that this framework provides natural...
Extensions of the Two Higgs Doublet model with a complex scalar singlet (2HDMS) can accommodate all current experimental constraints and are highly motivated candidates for Beyond Standard Model Physics. It can successfully provide a dark matter candidate as well as explain baryogenesis and provides gravitational wave signals. In this work, we focus on the dark matter phenomenology of the...
I will present a new class of renormalisable models, labelled Fermion Portal Vector Dark Matter, consisting of a dark SU(2)D gauge sector connected to the Standard Model through a Vector-Like fermion mediator, not necessarily requiring a Higgs portal, in which a massive vector boson is the Dark Matter candidate. Multiple realisations are possible, depending on the properties of the VL partner...
An almost pure Higgsino of 1.1 TeV of mass is still a viable candidate for thermal DM within the MSSM. I will show a couple of collider signatures at the LHC that could be the smoking gun of such a LSP.
The annihilation of TeV electroweak dark matter is subject to large electroweak corrections due to the Sommerfeld effect. In addition, for indirect detection, large Sudakov logarithms of electroweak scale vs dark matter mass and energy resolution require resummation to obtain reliable results. Far away from the endpoint, the electroweak parton shower, such as PPPC4DM, provide a more accurate...
GeV-scale dark matter particles with strong coupling to baryons evade the standard direct detection limits as they are efficiently stopped in the overburden and, consequently, are not able to
reach the underground detectors. On the other hand, novel direct detection bounds were found when the flux of dark matter particles boosted by interactions with cosmic rays was taken into account. We...
A massive astrophysical object deforms the local distribution of dark matter, resulting in a local overdensity of dark matter. This phenomenon is often referred to as gravitational focusing. In
the solar system, the gravitational focusing due to the Sun induces modulations of dark matter signals on terrestrial experiments. We consider the gravitational focusing of light bosonic dark matter...
We propose a novel mechanism for the production of dark matter (DM) from a thermal bath, based on the idea that DM particles can transform heat bath particles : ! . For a small initial abundance of this leads to an exponential growth of the DM number density, in close analogy to other familiar exponential growth processes in nature. We demonstrate that this mechanism complements...
I will illustrate a series of simple and minimal models aiming at providing an interpretation of observed anomalies in flavor physics, in particular g-2 and anomalies in decays of the B-mesons, and, at the same time, viable Dark Matter candidates achieving the correct relic density via the freeze-out paradigm.
Supersymmetry is an attractive new physics candidate that may explain the observed muon g-2 anomaly. MSSM can give large enough contribution to the muon g-2 only if there is (a) a large
higgsino-gaugino mixing, or (b) a large L-R mixing in the Bino-like LSP scenario. Both cases are strongly constrained by the dark matter constraint. For example, the former case is severely constrained by the...
Recently, many people have researched extensively dark matter models having dark sectors. Especially, MeV-scale dark matter can evade severe constraints from direct detections and is worth
considering its phenomenology. Those dark sector models often contain new light mediators. The mediators are produced in the early universe by the portal interactions and inject energy into the SM sector...
A t-channel singularity appears when the mediator of a given t-channel process is kinematically allowed to be on its mass-shell. If, moreover, the mediator is massive and stable, the singularity cannot be regularized within the standard Breit-Wigner approach or using known methods of IR-divergences regularization. Although that issue may affect processes both beyond and within the Standard...
Abelian U(1) gauge group extensions of the Standard Model represent one of the most minimal approaches to solve some of the most urgent particle physics questions and provide a rich phenomenology in various experimental searches. Baryophilic vector mediator decays into hadronic final states in the MeV-to-GeV mass range produce a challenging zoo of light hadronic resonances. Using only very...
Dilatons (and moduli) couple to the masses and coupling constants of ordinary matter, and these quantities are fixed by the local value of the dilaton field. If, in addition, the dilaton with mass mϕ contributes to the cosmic dark matter density, then such quantities oscillate in time at the dilaton Compton frequency. We show how these oscillations lead to broadening and shifting of the Voigt...
In this talk, I will discuss possibilities of producing dark matter in the early universe. By describing the transition between an inflationary epoch to a late time cosmology, I will emphasize how
the dynamics of the universe can affect dark matter production and leave a cosmological imprint, allowing some of these scenarios to be constrained.
One signature of an expanding universe is the time variation of the cosmological abundances of its different components. For example, a radiation-dominated universe inevitably gives way to a matter-dominated universe, and critical moments such as matter-radiation equality are fleeting. In this talk, I will stress that this lore is not always correct and that it is possible to obtain a form of...
According to the standard model of cosmology, the Universe at its very beginning underwent a phase of rapid, exponential expansion, followed by a reheating period. During this epoch, the energy density, initially accumulated in the oscillations of the inflaton field, was injected into the visible sector, eventually setting the initial conditions for the hot big bang. In this talk, I will...
Inflation is now very well motivated to solve many issues of the Big Bang scenario. Specific models of inflation potential can be tested by observations, most notably by the anisotropy spectrum of the CMB. In this talk, I propose to present some new results on gravitational matter production in the late time evolution of this inflationary field, during its coherent oscillation regime, usually...
Present and upcoming neutrino experiments can have considerable sensitivity to dark sectors that interact feebly with the Standard Model. We consider light dark sectors (DS) interacting with the SM through well-motivated irrelevant portals. We derive bounds on such scenarios using decay of dark sector excitations inside the neutrino detector, placed downstream from the target. Our approach is...
We study the impact of an alternate cosmological history with an early matter-dominated epoch on the freeze-in production of dark matter. Such early matter domination is triggered by a metastable matter field dissipating into radiation. In general, the dissipation rate has a non-trivial temperature and scale factor dependence. Compared to the usual case of dark matter production via the...
In this talk I will discuss the influence of non-perturbative effects,
namely Sommerfeld enhancement and bound state formation, on the cosmological production of non-thermal dark matter (DM). For this purpose, I will focus on a class of simplified models with t-channel mediators. These naturally combine the requirements for large corrections in the early Universe, i.e. beyond the Standard...
We consider a light non-thermal dark matter (DM) model that interacts with the Standard Model (SM) through a light mediator. The observed relic abundance in the Universe is obtained through the sequential freeze-in mechanism, where DM is produced from pair annihilation of mediator particles which are themselves produced by thermal collisions of SM particles. The light mediator, having leptonic...
In this talk, I will present a new theory of DM, qualitatively different from any existing proposal. I will present a theory, in which DM is made up of a novel form of matter, called “gapped continuum”. While ordinary elementary particles have unique masses - for example, each proton in the universe weighs exactly the same - the mass of DM states in our theory is a continuous parameter. I will...
Axion-like particles (ALPs), the QCD axion, are well motivated candidates for Cold Dark Matter. Such models may be divided into two classes depending on whether the associated U(1) symmetry is broken or not during inflation. The latter case is usually considered to be quite simple with relic density depending only on the corresponding decay constant and with no constraints from the known...
