Related papers: Muonic Boson Limits: Supernova Redux
In this study, the process $\gamma\gamma \to \gamma\gamma$ is investigated to establish constraints on anomalous Higgs boson couplings at $H\gamma\gamma$ vertice within the framework of the Standard Model Effective Field Theory (SMEFT). The…
Motivated by the long-standing discrepancy between the Standard Model prediction and the experimental measurement of the muon magnetic dipole moment, we have recently proposed to interpret this muon $g-2$ anomaly in terms of the loop effect…
We analyse the two-loop renormalization group (RG) flow of the gauge and Yukawa couplings within the E6 inspired supersymmetric (SUSY) models with extra U(1)_{N} gauge symmetry under which right-handed neutrinos have zero charge. In these…
We re-examine the bounds on supersymmetric particle masses in light of the new E821 data on the muon anomalous magnetic moment and the revised theoretical calculations of its hadronic contributions. The current experimental excess is either…
The most general supersymmetric model contains baryon number violating terms of the form $\lambda_{ijk}\;\ov{D}_i\, \ov{D}_j\, \ov{U}_k$ in the superpotential. We reconsider the bounds on these couplings, assuming that lepton number…
We elucidate the physical basis for the upper bound on high energy neutrino fluxes implied by the observed cosmic ray flux. We stress that the bound is valid for neutrinos produced either by p,gamma reactions or by p-p(n) reactions in…
Light hypothetical particles with masses up to $\mathcal{O}(100)\ {\rm MeV}$ can be produced in the core of supernovae. Their subsequent decays to neutrinos can produce a flux component with higher energies than the standard flux. We study…
Sterile neutrinos with masses up to $\mathcal{O} (100)$ MeV can be copiously produced in a supernova (SN) core, through the mixing with active neutrinos. In this regard the SN 1987A detection of neutrino events has been used to put…
A search for the resonant production of high mass photon pairs associated with a leptonic or hadronic system has been performed using a data sample of 57.7 pb-1 collected at an average center-of-mass energy of 182.6 GeV with the OPAL…
Muon colliders offer special opportunities to discover and study new physics. With the high intensity source of muons at the front end, orders of magnitude improvements would be realized in searches for rare muon processes, in deep…
Electromagnetic energy losses of charged pions and muons suppress the expected high energy, >1E18 eV, neutrino emission from sources of ultrahigh energy, >1E19 eV, cosmic-rays. We show here that >1E19 eV photons produced in such sources by…
We study the implications for bounds on the top quark pole mass m_t in models with low scale supersymmetry following the discovery of the Standard Model-like Higgs boson. In the minimal supersymmetric standard model, we find that m_t >= 164…
The most general supersymmetric model contains baryon number violating terms of the form $\lm_{ijk}\ \ov{D}_i\ \ov{D}_j\ \ov{U}_k$ in the superpotential. We reconsider the bounds on these couplings, assuming that lepton number conservation…
It is shown that top-bottom-tau Yukawa unification for \mu<0 can be consistent with (g-2)_\mu and b->s \gamma. This happens for non-universal gaugino masses which are assumed to be generated by the F-term vev in a 54-dimensional…
A gas cloud near a supernova remnant (SNR) provides a target for pp-collisions leading to subsequent gamma-ray emission through neutral pion decay. The assumption of a power-law ambient spectrum of accelerated particles with index near -2…
The effect of the recently observed 2.6 sigma deviation of the muon anomalous magnetic moment (a_mu = (g_mu -2)/2) from its Standard Model prediction is examined within the framework of supergravity models with grand unification and R…
We have studied anomalous four-photon couplings in the $\mu^+\mu^- \rightarrow \mu^+ \gamma\gamma \mu^-$ scattering at a future muon collider. The collision energies of 3 TeV, 14 TeV, and 100 TeV are addressed. Both differential and total…
We study the decays of a standard model-like MSSM Higgs boson to pairs of neutralinos, each of which subsequently decays promptly to a photon and a gravitino. Such decays can arise in supersymmetric scenarios where supersymmetry breaking is…
The simplest extension of the MSSM that does not contradict LEP II experimental bound on the lightest Higgs boson mass at $\tan\beta\sim 1$ is the modified Next-to-Minimal Supersymmetric Standard Model (MNSSM). We investigate the…
A degenerate sfermionic particle spectrum can escape constraints from flavor physics, and at the same time evade the limits from the direct searches if the degeneracy extends to the gaugino-higgsino sector. Inspired by this, we consider a…