Related papers: Neutron's Dark Secret
Dark sector particles at the GeV scale carrying baryon number provide an attractive framework for understanding the origin of dark matter and the matter-antimatter asymmetry of the universe. We demonstrate that dark decays of hadronic…
A brief sketch is given of the present observational status and future prospects of the physics of neutrino mass, including a survey of the various theoretical schemes of neutrino mass generation. Emphasis is given to those which are…
We conduct a systematic investigation of the influence of the nuclear symmetry energy on the proposed neutron decay into dark matter particles within the cores of neutron stars. Unlike the majority of previous studies that considered only…
The precise value of the mean neutron lifetime, $\tau_n$, plays an important role in nuclear and particle physics and cosmology. It is a key input for predicting the ratio of protons to helium atoms in the primordial universe and is used to…
The idea of a hidden sector of mirror partners of elementary particles has attracted considerable interest as a possible candidate for dark matter. Recently it was pointed out by Berezhiani and Bento that the present experimental data…
We consider a class of models involving interactions between ultra-light scalar dark matter and Standard Model neutrinos. Such couplings modify the neutrino mass splittings and mixing angles to include additional components that vary in…
We report a novel neutron interferometry scheme aimed at probing the potential existence of mirror neutrons, which have been proposed as viable dark matter candidates. Our theoretical analysis demonstrates that if mirror neutrons exist,…
Recent observational results for the masses and radii of some neutron stars are in contrast with typical observations and theoretical predictions for "normal" neutron stars. We propose that their unusual properties can be interpreted as the…
We explore the hypothesis that the unexplained data from LSND and MiniBooNE are evidence for a new, heavy neutrino mass-eigenstate that mixes with the muon-type neutrino and decays into an electron-type neutrino and a new, very light scalar…
Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from…
Various issues in neutrino phenomenology are reviewed, including: the possibility of large mixing angles in various models for neutrino masses, difficulties for degenerate neutrinos as candidates for hot dark matter, strategies for…
We briefly review the theoretical and experimental results concerning decays of positronium. Possible solutions of the "orthopositronium lifetime puzzle" are discussed. Positronium annihilation into neutrinos is examined and disagreement is…
New measurements of the cosmic microwave background (CMB) by the Planck mission have greatly increased our knowledge about the Universe. Dark radiation, a weakly interacting component of radiation, is one of the important ingredients in our…
It is well-known that the momentum spectra of particles confined to finite spatial volumes deviate from the continuous spectra used for unconfined particles. In this article, we consider real scalar particles confined to finite volumes with…
As we have pointed out in (arXiv:1806.10107 [hep-ph]), the existence of neutron dark matter decay modes "n -> chi + anything", where "chi" is a dark matter fermion, for the solution of the neutron lifetime problem changes priorities and…
The neutron is a well-suited system to search for a violation of time reversal invariance beyond the Standard Model. Recent experiments and projects searching for time reversal violation in the neutron decay and in the neutron electric…
We study a model of dark matter in which the hidden sector interacts with standard model particles via a hidden photonic portal. We investigate the effects of this new interaction on the hydrogen atom, including the Stark, Zeeman and…
In the model of hidden sector proposed recently, protons and neutrons scatter differently on cold-dark-matter particles. First, we summarize briefly our model based on a mechanism of "photonic portal" between hidden and Standard-Model…
We focus on a novel baryon-number ($\mathcal{B}$) violating process within neutron stars, where two neutrons convert into two dark photons ($nn \rightarrow VV$) via new Higgs-like scalar bosons. This process is believed to be greatly…
We study scenarios where loop processes give the dominant contributions to dark matter decay or annihilation despite the presence of tree level channels. We illustrate this possibility in a specific model where dark matter is part of a…