Related papers: Mediator Decay through mixing with Degenerate Spec…
So far, the observed effects of dark matter are compatible with it having purely gravitational interactions. However, in many models, dark matter has additional interactions with itself, with the Standard Model, and/or with additional…
Despite overwhelming observational evidence for dark matter, we still have no evidence of direct detection. Consequently, our knowledge about dark matter is limited, for example, we do not know if dark matter is a stable particle or if it…
We consider a minimal renormalizable and gauge invariant dark matter (DM) model, in which the singlet fermion DM has only axial couplings to a new pseudoscalar mediator. The mixing between the pseudoscalar mediator and the standard model…
Many collider searches have attempted to detect the Higgs boson decaying to a photon and an invisible massless dark photon. For the branching ratio to this channel to be realistically observable at the LHC, there must exist new mediators…
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. In this…
Many attempts have been made to observe the decay of the Higgs boson to a photon and an invisible massless dark photon. For this decay to be potentially observable at the LHC, new mediators that communicate between the Standard Model and…
Many models containing particles which are candidates for dark matter, assume the standard model particles and the dark matter candidates are mediated by a spin-0 particle. At the LHC, one can use these models for dark matter searches. One…
LHC searches have revealed that the Higgs boson decay to a photon pair is nearly consistent with the Standard Model (SM), whereas recently, there is evidence for the decay of the Higgs boson to a $Z$-boson and a photon. These decays are…
We compute the branching fractions of vector quarkonia ($V_Q=J/\psi, \psi', \Upsilon(nS)$) decays into neutrino pairs, considering both Dirac and Majorana types, within the Standard Model (SM) and beyond. The vector nature of quarkonium…
Within the hypothesis of the dark-matter origin of the excess in $B\to K M_X$ decays over the standard-model expectation, observed by Belle-II, we show that: (i) Scalar- and vector-medator scenarios may be unambiguously discriminated by…
The vector-like quark model is one of the extensions of the standard model (SM) of particle physics. The simplest version of this model introduces a vector-like singlet quark which can mix with SM quarks and give rise to new contributions…
Solitons are observed to form in simulations of dark matter (DM) halos consisting of bosonic fields. We use the extended Press-Schechter formalism to compute the mass function of solitons, assuming various forms for the relationship between…
Light vector mediators can naturally induce velocity-dependent dark matter self-interactions while at the same time allowing for the correct dark matter relic abundance via thermal freeze-out. If these mediators subsequently decay into…
A light meta-stable dark photon decaying into collimated electron/positron pair can fake a photon, either converted or unconverted, at the LHC. The detailed object identification relies on the specifics of the detector and strategies for…
We study the dark matter particle, the dark photon (DP), in the decay of the Higgs-like boson. The nature of dark matter is maintained through the hidden sector including the effects of breaking of the scale invariance. The model is based…
We consider two body decays of B meson into a light vector (V) and a pseudoscalar (P) meson. The constraint obtained from the $B\to P P$ modes on the parameter space of the input parameters is imposed also on $B\to V P$ modes. In particular…
Motivated by the most recent measurement of tau polarization in $Z\to \tau^+\tau^-$ by CMS, we have introduced a new $U(1)_X$ gauge boson field X, which can have renormalizable kinetic mixing with the standard model $U(1)_Y$ gauge boson…
We present a search for the e+e- decay of a hypothetical dark photon, also names U vector boson, in inclusive dielectron spectra measured by HADES in the p (3.5 GeV) + p, Nb reactions, as well as the Ar (1.756 GeV/u) + KCl reaction. An…
The ultralight boson represents a promising dark matter candidate exhibiting unique wave-like behaviors. These properties could transfer to the dark mediator, such as the kinetic mixing dark photon, which can be a link between the dark and…
The phenomenological implications to the decay of the neutral pion from the introduction of new dark particles are discussed. We calculate the contribution to the $\pi^0$ decay width and then we extend the theory by adding dark sector…