Related papers: Proton Decay
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…
Naturally small Majorana neutrino masses arise from nonstandard supersymmetry breaking terms. This mechanism works in the minimal supersymmetric framework and does not require extra particles or new mass scales. It could also be responsible…
Different decompositions (sum rules) for the proton mass have been proposed in the literature. All of them are related to the energy-momentum tensor in quantum chromodynamics. We review and revisit these decompositions by paying special…
The existing discrepancy between neutron lifetime measurements in bottle and beam experiments has been interpreted as a sign of the neutron decaying to dark particles. We summarize the current status of this proposal, including a discussion…
We discuss proton decay in a recently proposed model of supersymmetric hybrid inflation based on the gauge symmetry $SU(4)_c \times SU(2)_L \times SU(2)_R$. A $U(1)\, R$ symmetry plays an essential role in realizing inflation as well as in…
The theoretical and experimental issues relevant to neutrinoless double-beta decay are reviewed. The impact that a direct observation of this exotic process would have on elementary particle physics, nuclear physics, astrophysics and…
Neutrino decay in vacuum has often been considered as an alternative to neutrino oscillations. Because non-zero neutrino masses imply the possibility of both neutrino decay and neutrino oscillations, we present a model-independent formal…
The neutron lifetime anomaly has been used to motivate the introduction of new physics with hidden-sector particles coupled to baryon number, and on which neutron stars provide powerful constraints. Although the neutron lifetime anomaly may…
A delicate interplay between the anomalous magnetic moments of the proton and neutron makes, in magnetic fields $B\ge 2\times 10^{14}$ T, the neutron stable and for fields $B\ge 5\times 10^{14}$ T the proton becomes unstable to a decay into…
The increasing precision of the measurements on the proton structure and an improved treatment of the correlated systematic experimental errors constitute a major step forward in our understanding of the flavour decomposition of the proton…
We propose a new grand unification scenario for ensuring proton stability. Our scenario is based on the idea that the proton decay problem is an artificial one, which is caused from the identification of the gauge coupling unification scale…
A recent proposal suggests that experimental discrepancies on the lifetime of neutrons can be resolved if neutrons decay to dark matter. At the same time it has been demonstrated that such a decay mode would soften the nuclear equation of…
Properties and experimental predictions of a broad class of supergravity grand unified models possessing an $SU(5)$-type proton decay and $R$ parity are described. Models of this type can be described in terms of four parameters at the Gut…
Experiments with cold and ultracold neutrons have reached a level of precision such that problems far beyond the scale of the present Standard Model of particle physics become accessible to experimental investigation. Due to the close links…
The explanation of various observed phenomena such as large angle neutrino oscillations, hierarchies of charged fermion masses and CKM mixings, and apparent baryon number conservation may have a common origin. We show how this could occur…
The well-known baryon and lepton numbers of the standard model of quarks and leptons are extended to include new fermions and bosons in a simple structure with several essential features. The usual heavy right-handed neutrino singlets (for…
Precision measurements of neutron decay offer complementary access to particle physics at small distance scales or high energies. In particular they allow tests of the V-A structure of the weak interaction. Among many experimental…
Processes that violate baryon number, most notably proton decay and $n\bar n$ transitions, are promising probes of physics beyond the Standard Model (BSM) needed to understand the lack of antimatter in the Universe. To interpret current and…
We investigate the decay of accelerated protons and neutrons. Calculations are carried out in the inertial and coaccelerated frames. Particle interpretation of these processes are quite different in each frame but the decay rates are…
Neutrinoless double-beta decay is a forbidden, lepton-number-violating nuclear transition whose observation would have fundamental implications for neutrino physics, theories beyond the Standard Model and cosmology. In this review, we…