相关论文: Dirac gaugino as leptophilic dark matter
We propose a novel cogenesis mechanism by utilising the two-body decay of heavy vector-like fermions to dark matter (DM) $\chi$ and right chiral part of light Dirac neutrino $\nu_R$ via the electromagnetic dipole operator. This leads to…
In this work, we make a detailed discussion on the phenomenology of the scotogenic Dirac model, which could accommodate the Dirac neutrino mass and dark matter. We have studied the LFV processes in this model, which are mediated by the…
Models of inelastic (or pseudo-Dirac) dark matter commonly introduce a gauge symmetry spontaneously broken by the introduction of a dark sector version of the Higgs mechanism. We find that this ubiquitous introduction of two extra fields, a…
We analyze the direct detection signals of a toy model consisting of a Dirac dark matter particle which couples to one Standard Model fermion via a scalar mediator. For all scenarios, the dark matter particle scatters off nucleons via one…
Since the PAMELA results on the "anomalously" high positron fraction and the lack of antiproton excess in our Galaxy, there has been a tremendous number of studies advocating new types of dark matter, with larger couplings to electrons than…
Recently published results from the PAMELA experiment have shown conclusive evidence for an excess of positrons at high (~ 10 - 100 GeV) energies, confirming earlier indications from HEAT and AMS-01. Such a signal is generally expected from…
The strong direct detection limits could be pointing to dark matter -- nucleus scattering at loop level. We study in detail the prototype example of an electroweak singlet (Dirac or Majorana) dark matter fermion coupled to an extended dark…
I point out several terms in the low energy effective Lagrangian of the Pyramid Scheme, which were missed in a previous analysis of the phenomenological consequences of the model. They lead to a Dirac contribution to the gluino mass, much…
The issue of a Majorana, Dirac or pseudo-Dirac mass for gauginos must not be reduced to a question of an extension of the Minimal Supersymmetric Standard Model by extra states, parameters and phenomenological implications. On the contrary,…
We discuss the Higgs phenomenology in models with a new $U(1)_X$ gauge symmetry including the $U(1)_{B-L}$ scenario, where three right-handed neutrinos are inevitably introduced due to the gauge anomaly cancellations. We find that the decay…
While much supersymmetric weakly interacting massive particle (WIMP) parameter space has been ruled out, one remaining important candidate is Higgsino dark matter. The Higgsino can naturally realize the "inelastic dark matter" scenario,…
Dirac neutrino masses require two distinct neutral Weyl spinors per generation, with a special arrangement of masses and interactions with charged leptons. Once this arrangement is perturbed, lepton number is no longer conserved and…
We study the constraints on neutralino dark matter in minimal low energy supersymmetry models and the case of heavy lepton and quark scalar superpartners. For values of the Higgsino and gaugino mass parameters of the order of the weak…
We consider a simple model of a dark sector with a chiral $U(1)$ gauge symmetry. The anomaly-free condition requires at least five chiral fermions. Some of the fermions acquire masses through a vacuum expectation value of a Higgs field, and…
Supersymmetric models with a Dirac gluino have been shown to be considerably less constrained from LHC searches than models with a Majorana gluino. In this paper, we generalize this discussion to models with a "Mixed Gluino", that acquires…
A chiral fourth generation is a simple and well motivated extension of the standard model, and has important consequences for Higgs phenomenology. Here we consider a scenario where the fourth generation neutrinos are long lived and have…
We consider an SU(3)'_c\times SU(2)'_L\times U(1)'_Y dark sector, parallel to the SU(3)_c\times SU(2)_L\times U(1)_Y ordinary sector. The hypercharges, baryon numbers and lepton numbers in the dark sector are opposite to those in the…
We investigate purely leptonic decays of leptons $\l^{\prime-}\to l^-\bar{\nu}_l\nu_{l^{\prime}}$ to distinguish Dirac or Majorana neutrinos. We derive the differences of the decay width (and associated quantities) between the two neutrino…
We present an R-parity conserving model of sneutrino dark matter within a Higgs-philic U(1)' extension of the minimal supersymmetric standard model. In this theory, the mu parameter and light Dirac neutrino masses are generated naturally…
Gluinos and neutralinos, supersymmetric partners of gluons and neutral electroweak gauge and Higgs bosons, are Majorana particles in the Minimal Supersymmetric Standard Model [MSSM]. Decays of such self-conjugate particles generate charge…