Related papers: How Long Could We Live?
We present a comprehensive analysis of a supersymmetric $SO(10)$ Grand Unified Theory, which is broken to the Standard Model via the breaking of two intermediate symmetries. The spontaneous breaking of the first intermediate symmetry,…
We discuss baryon and lepton violation in the context of a simple 5-dimensional grand unified model, based on the orbifold S^1/(Z_2 x Z_2'). While gauge and Higgs degrees of freedom live in the bulk, matter is located on the boundaries of…
We searched for bound neutron decay via $n\to\bar{\nu}+K^0$ predicted by the Grand Unified Theories in 0.401 Mton$\cdot$years exposure of all pure water phases in the Super-Kamiokande detector. About 4.4 times more data than in the previous…
Experimental studies of neutron decay, $n\to pe\bar\nu$, exhibit two anomalies. The first is a 8.6(2.1)s, roughly $4\sigma$ difference between the average beam measured neutron lifetime, $\tau_n^\text{beam}=888.0(2.0)$s, and the more…
We derive 95% CL lower limits on the lifetime of decaying dark matter in the channels $Z\nu$, $W\ell$ and $h\nu$ using measurements of the cosmic-ray antiproton flux by the PAMELA experiment. Performing a scan over the allowed range of…
We study visible neutrino decay at the reactor neutrino experiments KamLAND and, JUNO. Assuming the Majoron model of neutrino decay, we obtain constraints on the couplings between Majoron and neutrino as well as on the lifetime/mass of the…
The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. The neutron lifetime recently obtained, 878.5 +/- 0.7stat +/- 0.3sys s, is the most accurate one to date. The new result for the…
We discuss a supersymmetric grand unified model which has gauge group SU(5) $\times$ SU(5) $\times$ SU(5), with matter fields transforming asymmetrically under different gauge SU(5) groups. We observe that the gauge structure of the model…
We study the production of antineutrinos from the solar neutrinos due the Majorana neutrino decays of neutrino to antineutrino. Using the antineutrino spectra from KamLAND and Borexino, we present newest limits on the lifetime of $\nu_{3}$…
Within a chiral $SU(15)$ gauge theory in which the Standard Model fermions are bound states of massless preons, we show that proton-decay operators are likely induced at the compositeness scale, $\Lambda_{\rm pre}$. Our estimate of the…
(Abridged) Neutrino interactions beyond the standard model may affect the cosmological evolution and can be constrained through observations. We consider the possibility that neutrinos possess secret scalar or pseudoscalar interactions…
Proton decay is one of the most important predictions of the grand unified theory (GUT). In the supersymmetric (SUSY) GUT, proton decays via the dimension-five operators need to be suppressed. In the $SO(10)$ model where ${\bf…
We comment on the status and prospects of the minimal non-supersymmetric renormalizable SO(10) grand unified model. We emphasize its unique predictive power owing to the particular robustness of the gauge unification pattern to the…
We consider a phenomenologically viable SO(10) grand unification model of the unification scale $M_G$ around $10^{16} $ GeV which reproduces the MSSM at low energy and allows perturbative calculations up to the Planck scale $M_P$ or the…
We construct a four-dimensional SU(5) grand unified theory in which the proton is stable. The Standard Model leptons reside in the 5 and 10 irreps of SU(5), whereas the quarks live in the 40 and 50 irreps. The SU(5) gauge symmetry is broken…
Dark matter candidates and proton decay in a class of models based on the AdS/CFT correspondence are discussed. We show that the present bound on the proton decay lifetime is inconsistent with ${\cal N} = 1$ SUSY, and strongly constrains…
The author considers a hypothesis of neutron lifetime splitting in beta-decay and shows that the beta-decay of neutrons could be described by the triad of lifetimes tau_{Left}, tau_{Mean}, tau_{Right}. The lifetime tau_{Left} is the…
A constraint on masses of superheavy gauge and Higgs multiplets at the grand unification (GUT) scale is obtained from the gauge coupling unification in the case of high-scale supersymmetry. We found that all of the particles may lie around…
We propose simpler Higgs sectors in $E_6$ grand unified theory with anomalous $U(1)_A$ gauge symmetry than the previous model in Ref.1). As in the previous model, the doublet-triplet splitting can be realized in a natural way, while proton…
We study the mass scales in the $SO(10)$ grand unified theory based on the following minimal Higgs representation content: adjoint $45_{\rm H}$, spinor $16_{\rm H}$ and complex vector $10_{\rm H}$, with higher dimensional operators on top…