Related papers: Constraining Light Thermal Inelastic Dark Matter w…
Despite the robust cosmological and astrophysical evidence confirming the existence of a non-baryonic matter component in the Universe, the underlying nature of Dark Matter (DM) remains a mystery. Among the several possible scenarios, light…
Thermal light dark matter (LDM) with particle masses in the 1 MeV - 1 GeV range could successfully explain the observed dark matter abundance as a relic from the primordial Universe. In this picture, a new feeble interaction acts as a…
We present a comprehensive study of the Muonic Portal to Vector Dark Matter (MPVDM), a minimal extension of the Standard Model featuring a new $SU(2)_D$ gauge symmetry and vector-like muons that mediate interactions between the dark sector…
We present a model featuring sub-GeV vector dark matter by augmenting the Standard Model with a new non-Abelian dark $SU(2)_D$, spontaneously broken by the vacuum expectation values of a scalar doublet and a triplet. Interactions between…
In rich dark sector models, dark photons heavier than tens of MeV can behave as semi-visible particles: their decays contain both visible and invisible final states. We present models containing multiple dark fermions which allow for such…
The NA64 electron beam program comprises of a high sensitivity search for visible and invisible decays of the hypothetical dark photon, $A'$, with a goal to either observe the sub-GeV Dark Matter mediator or exclude most of the model…
The current most stringent constraints for the existence of sub-GeV dark matter coupling to Standard Model via a massive vector boson $A^\prime$ were set by the NA64 experiment for the mass region $m_{A^\prime}\lesssim 250$ MeV, by…
We systematically study light (< few GeV) Dark Matter (DM) models that thermalize with visible matter through the Higgs portal and identify the remaining gaps in the viable parameter space. Such models require a comparably light scalar…
We examine the vector-portal inelastic dark matter (DM) model with DM mass $m_\chi$ and dark photon mass $m_{A'}$, in the `forbidden dark matter' regime where $1 \lesssim m_{A'}/m_\chi \lesssim 2$, carefully tracking the dark sector…
Thermal dark matter models with particle $\chi$ masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and…
We calculate direct detection constraints on inelastic dark matter (DM) for a scalar portal scenario with leptophilic couplings. The p-wave velocity suppression of the annihilation cross section of scalar-mediated inelastic Dirac DM implies…
Inelastic dark matter scenarios have attracted considerable attention in contemporary particle physics. In this study, we investigate the phenomenology of sub-GeV inelastic dark matter interacting via a lepton-specific scalar portal. By…
GeV-scale thermal dark matter (DM) is highly constrained by the null results of both direct and indirect detection experiments, especially in the context of simplified models. In this work, we study the interplay of collider, direct and…
Inspired by the recently new measurement of $(g-2)_{\mu}$ at FermiLab and reported upper bound for electron-dark matter (DM) recoil by the XENON1T collaboration, we revisited phenomenology of a light MeV scale vector dark matter in a…
We discuss prospects of searching for a dark photon ($A'$) which serves as mediator between Standard model (SM) particles and light dark matter (LDM) by using the combined results from the NA64 experiment at the CERN SPS running in…
We report on a search for a new $Z'$ ($L_\mu-L_\tau$) vector boson performed at the NA64 experiment employing a high energy muon beam and a missing energy-momentum technique. Muons from the M2 beamline at the CERN Super Proton Synchrotron…
In this research we consider a $U(1)_X$ gauge boson acting as a dark matter candidate. The vector dark matter (DM) gets mass when a complex singlet scalar breaks the gauge symmetry spontaneously, adding a second Higgs boson to the spectra.…
We test a novel idea of using a $\pi^-$ beam in the fixed-target experiments to search for New Physics in the events with missing energy. Bounds for invisible vector $\rho$ meson decay were derived, analyzed, and compared with the current…
Some extensions of the Standard Model consider inelastic dark matter (iDM) as an attractive candidate for sub-GeV DM of thermal origin that could be detected at modern accelerators. In the present paper, we calculate the production rate of…
We investigate the prospects for detecting light leptophilic dark sectors with a missing-momentum experiment at NA64 running in muon mode. In particular, we consider models in which dark matter connects to the visible sector through a…