Related papers: Proton Decay in Intersecting D-brane Models
We have searched for proton decays via p -> e^+ pi^0 and p -> mu^+ pi^0 using data from a 91.7 kiloton year exposure of Super-Kamiokande-I and a 49.2 kiloton year exposure of Super-Kamiokande-II. No candidate events were observed with…
We recapitulate the primary sources of theoretical uncertainties in proton lifetime estimates in renormalizable, four-dimensional and non-supersymmetric grand unifications that represent the most conservative framework in which this…
Two-proton (2$p$) radioactivity is a rare decay mode found in a few proton-unbound nuclei. The $2p$-decay lifetime and properties of emitted protons carry invaluable information on nuclear structure in the presence of low-lying proton…
We make a detailed analysis of gauge coupling unification in supersymmetry. When the Standard Model gauge group is embedded in a Grand Unified Theory, new particles often appear below the GUT scale in order to predict the right…
We discuss proton and neutron decays involving three leptons in the final state. Some of these modes could constitute the dominant decay channel because they conserve lepton-flavor symmetries that are broken in all usually considered…
In the Standard Model, no dim-5 $\Delta B \neq 0$ operators exist, so that Planck-scale-induced proton decay amplitudes are suppressed by at least $1/M^2_{P \ell}$. If the Standard Model is augmented by a light, color-non-singlet boson,…
The proton radioactivity half-lives of spherical proton emitters are investigated theoretically. The potential barriers preventing the emission of protons are determined in the quasimolecular shape path within a generalized liquid drop…
We study the non-linear realization of supersymmetry. We classify all lower dimensional operators, describing effective interactions of the Goldstino with Standard Model fields. Besides a universal coupling to the energy momentum tensor of…
Proton decay is a baryon number violating process, and hence is forbidden in the Standard Model (SM) of particle physics. Baryon number violation is expected to be an important criteria to explain the matter-anti-matter asymmetry of the…
The various decay modes of the type $B \to \gamma D^* $ are dynamically different. In general there are factorizable contributions, and there are pole diagrams and pseudoscalar exchange contributions at meson level. The purpose of this…
In this talk we show that it is possible to find an upper bound on the total proton lifetime. We conclude that the minimal realistic non-supersymmetric grand unified theory is the modified Georgi-Glashow model with a Higgs sector composed…
The success of SU(5)-like gauge coupling unification boundary conditions $g_3^2=g_2^2=5/3 g_1^2$ has biased most attempts to embed the SM interactions into a unified structure. After discussing the limitations of the orthodox approach, we…
We show that in generic leptoquark (LQ) extensions of the standard model lepton and baryon numbers are broken at the level of renormalizable operators. In particular, this may cause fast proton decay unless the leptoquarks are heavy enough.…
The beta decay of 31Ar, produced by fragmentation of a 36Ar beam at 880 MeV/nucleon, was investigated. Identified ions of 31Ar were stopped in a gaseous time projection chamber with optical readout allowing to record decay events with…
Giving up the solutions to the fine-tuning problems, we propose the non-supersymmetric flipped $SU(5)\times U(1)_X$ model based on the minimal particle content principle, which can be constructed from the four-dimensional $SO(10)$ models,…
We perform a detailed study of the grand unified theories $SO(10)$ and $E(6)$ with left-right intermediate gauge symmetries of the form $SU(N)_L\otimes SU(N)_R \otimes \mathcal{G}$. Proton decay lifetime constrains the unification scale to…
We analyze gauge coupling unification in the context of heterotic strings on anisotropic orbifolds. This construction is very much analogous to effective 5 dimensional orbifold GUT field theories. Our analysis assumes three fundamental…
I review the theoretical and experimental status of proton decay theory and experiment. Regarding theory, I focus mostly, but not only, on grand unification. I discuss only the minimal, well established SU(5) and SO(10) models, both…
We study several different kinds of bound states built from D-branes and orientifolds. These states are to atoms what branonium - the bound state of a brane and its anti-brane - is to positronium, inasmuch as they typically involve a light…
The production of the isoscalar Jp = 3+ didelta dibaryon d* by proton inelastic scattering from deuteron targets is described in a double-scattering Glauber approximation. Each scattering changes a target nucleon into a Delta with the help…