Conveners
Open Session B): #1
- Michel Tytgat (Université Libre de Bruxelles)
- Oliver Buchmuller (Imperial College (GB))
Open Session B): #2
- Oliver Buchmuller (Imperial College (GB))
- Michel Tytgat (Université Libre de Bruxelles)
While the LHC "mono-X" like searches have a mild (few 100 GeVs) reach for WIMPs due to the small EW cross section and the large V+jets backgrounds, models where dark matter is mostly part of a weak multiplet (Minimal Dark Matter) can be probed via the long-livedness of the electrically charged members of the multiplet. Using the benchmark-case of a weak doublet (pure-Higgsinos in SUSY) I will...
Many dark matter models predict monojet signatures at colliders. However, if the dark sector also contains long-lived particles, less conventional signatures can arise. In this talk I will discuss this possibility by considering two different models: the "pseudo-Dirac model", which predicts displaced vertices, and the "chromo-electric dipole model", which is characterized by composite states...
Recent results are presented on searches at LHCb for both prompt-like and long-lived dark photons, produced in proton-proton collisions at a center-of-mass energy of 13 TeV, using decays into two muons. A search for long-lived particles with a mass between 25 and 50 GeV/c² and a lifetime between 2 and 500 ps is presented as well, where the signature is a single long-lived particle identified...
We introduce a new class of simplified models to address the effects of 3-point interactions between the dark matter particle, its dark co-annihilation partner, and the Standard Model degree of freedom, which we take to be the tau lepton. We investigate these effects as well as the discovery potential for dark matter co-annihilation partners at the LHC. A small mass splitting between the dark...
Besides for the LHC, also for modelling of the development of the
Cosmic Ray (CR) Air Showers, diffractive processes need to be studied.
Dark Matter (DM) is assumed to be produced in hadronic interaction.
In the transverse shower plane on ground the incoming muons from Air
Showers add to zero 3-momentum. A large area Muon Detector, located
within the KASCADE-Grande Air Shower experiment, has...
We explore the full constraining power of experimental bounds derived for hidden photons by applying them to gauge bosons of a weakly coupled $U(1)_{B-L}$, $U(1)_{L_\mu-L_\tau}$, $U(1)_{L_\mu-L_e}$ and $U(1)_{L_\tau-L_e}$. The associated gauge bosons of these anomaly-free groups are well-motivated mediators to a dark sector. In contrast to a hidden photon that acquires universal couplings to...
The Super Cryogenic Dark Matter Search (SuperCDMS) is a direct dark matter search experiment designed to observe nuclear recoils induced by WIMPs. However, it is also sensitive to dark photons, producing an electron recoil signature. SuperCDMS uses cryogenic detectors in two configurations: one has an excellent capability to discriminate between electron and nuclear recoils, while the other...
This work is based on the so-called Scotogenic model which enhances the Standard Model with a second Higgs doublet and three right-handed neutrinos as gauge singlets. An additional Z_2 symmetry is proposed under which all new particles are charged.
This allows for a stable DM candidate in the keV-range and a radiative generation of active neutrino masses. Also I want to address the question...
Recent hints of lepton flavour universality violation motivate searches
for lepton flavour violating B decays.
The LHCb experiment is particularly suited for these searches due to its
large acceptance,
high trigger efficiencies and excellent tracking and particle
identification capabilities.
Recent results from LHCb on searches for the lepton flavour violating
decays B(s)->emu will be presented.
Dark Matter might be an accidentally stable baryon of a new confining gauge inter- action. I will explore the possibility that the DM is made of dark quarks. The resulting phenomenology contains new unusual elements: a two-stage DM cosmology, a large DM annihilation cross section through recombination of dark quarks. Light dark glue-balls are relatively long lived and give extra cosmological...
The NEWSdm experiment, based on nuclear emulsions, is a new experiment proposal intended to measure the direction of WIMP-induced nuclear recoils with a solid-state detector, thus with a high sensitivity. We discuss the discovery potential of a directional experiment based on the use of a solid target made of newly developed nuclear emulsions and novel read-out systems achieving nanometric...
Chemical equilibrium is a commonly made assumption in the freeze-out calculation of coannihilating dark matter. We explore the possible failure of this assumption and find a new conversion-driven freeze-out mechanism. Considering a representative simplified model we find regions in parameter space with very small couplings accommodating the measured relic density. In this region freeze-out...
We propose a hybrid framework in the form of an effective theory, including both the dark matter states and a mediator connecting the former to the Standard Model fields. The framework overcomes the problems of traditional DM-EFT regarding the validity at high energies at collider experiments and improves the generality of the simplified models.
For fermionic and scalar dark matter with a...
The results of the monojet search using $36.1~\rm{fb}^{-1}$ of $\sqrt{s} = 13~\rm{TeV}$ data from the ATLAS detector are reinterpreted in the context of a search for the associate production of an axion-like CP-odd boson and a gluon. Such processes are predicted by models addressing the strong CP problem of QCD [1], leading to a variety of signatures which depend on the assumed couplings of...
