相关论文: Metastable GeV-scale particles as a solution to th…
We revisit the impact of heavy neutrinos with masses in the MeV-GeV range on neutrinoless double beta decay ($0\nu\beta\beta$) in view of updated results for the lifetime of this process. Working in a minimal realistic extension of the…
At present, cosmological observations set the most stringent bound on the neutrino mass scale. Within the standard cosmological model ($\Lambda$CDM), the Planck collaboration reports $\sum m_\nu < 0.12\,\text{eV}$ at 95% CL. This bound,…
Results of a detailed examination of the cascade nucleosynthesis resulting from the putative hadronic decay, evaporation, or annihilation of a primordial relic during the Big Bang nucleosynthesis (BBN) era are presented. It is found that…
Nucleon decays are generic predictions of motivated theories, including those based on the unification of forces and supersymmetry. We demonstrate that non-canonical nucleon decays offer a unique opportunity to broadly probe light new…
Recent spectroscopic observations of metal poor stars have indicated that both $^7$Li and $^6$Li have abundance plateaus with respect to the metallicity. Abundances of $^7$Li are about a factor three lower than the primordial abundance…
The success of primordial nucleosynthesis as a cornerstone of the hot Big Bang model has been limited by the long-standing lithium problem. Recent work presented a self-consistent perturbative analysis of the effects of variations in…
We derive constraints on the couplings of light vector particles to all first-generation Standard Model fermions using leptonic decays of the charged pion, $\pi^+\to e^+ \nu_e X_\mu$. In models where the net charge to which $X_\mu$ couples…
Unstable heavy particles well above the TeV scale are unaccessible experimentally. So far, Big-Bang Nucleosynthesis (BBN) provides the strongest limits on their mass and lifetime, the latter being shorter than 0.1 second. We show how these…
The vacuum expectation value $v_s$ of a Higgs triplet field $\Delta$ carrying two units of lepton number $L$ induces neutrino masses $\propto v_s$. The neutral component of $\Delta$ gives rise to two Higgs particles, a pseudoscalar $A$ and…
A new observation of D in a primordial gas cloud, made using the high resolution spectrograph at the Keck telescope, indicates an abundance $ D/H =(1.9-2.5) \times 10^{-4}$ \cite{SCHR}. Since deuterium is destroyed by stars, and the…
The origin of both the diffuse high-latitude MeV gamma-ray emission and the 511 keV line flux from the Galactic bulge are uncertain. Previous studies have invoked dark matter physics to independently explain these observations, though as…
The MiniBooNE collaboration recently released a report claiming have observed an excess of electron and anti-electron neutrino with significance of $4.8 \, \sigma$ C.L. corroborating, in this way, the long-standing LSND anomaly. Combined…
The observation of cosmic--ray events above the Greisen-Kuzmin-Zatsepin (GZK) cutoff of $\sim 5\times 10^{19}$ eV challenges orthodox modeling. We discuss a possible solution which uses standard hot Big Bang cosmology and Standard Model…
Cosmological baryon asymmetry B is studied in supersymmetric standard models, assuming the electroweak reprocessing of B and L. Only when the soft supersymmetry breaking is taken into account, B is proportional to the primordial B-L in the…
The Standard Model is by far the most encompassing physics theory. With the recent discovery of the Higgs Boson, the Standard Model has performed extremely well against experimental data. However, the theory is intrinsically not complete,…
The unresolved nuclear region of M87 emits strong non-thermal emission from radio to X-rays. Assuming this emission to originate in the pc scale jet aligned at $\theta \sim 30^\circ$ to the line of sight, we interpret this emission in the…
We calculate the fluxes of 511 KeV photons from the Galactic bulge caused by positrons produced in the decays of relic particles with masses less than 100 MeV. In particular, we tighten the constraints on sterile neutrinos over a large…
Many particles predicted by extensions of the Standard Model feature interactions with neutrinos, e.g., Majoron-like bosons $\phi$. If the mass of $\phi$ is larger than about 10 keV, they can be produced abundantly in the core of the next…
We study the model with three right-handed neutrinos which masses are smaller than the weak scale ${\cal O}(10^2)$ GeV (called as the $\nu$MSM). The model can explain the origin of neutrino masses by the seesaw mechanism, offer a candidate…
We consider the prospects for observing the effects of quantum decoherence in high-energy (TeV-PeV) neutrinos from astrophysical sources. In particular, we study Galactic sources of electron anti-neutrinos produced in the decay of…