Related papers: Improved Lower Bounds on Partial Lifetimes for Nuc…

Most studies on baryon number violating (BNV) processes in the literature focus on free or bound nucleons in nuclei, with limited attention given to the decay of bound atoms. Given that hydrogen is the most abundant atom in the universe, it…

We compute the fully differential rate for the Higgs-boson decay $h\to Z\ell^+\ell^-$, with $Z\to\ell^{'+}\ell^{'-}$. For these processes we assume the most general matrix elements within an effective Lagrangian framework. The electroweak…

Baryons with three heavy quarks are the last missing pieces of the lowest-lying baryon multiplets in the quark model after the discovery of doubly heavy baryons. In this work, we study nonleptonic weak decays of triply heavy baryons…

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…

Leptonic rare decays of $B^0_{s,d}$ mesons offer a powerful tool to search for physics beyond the Standard Model. The $B^0_{s}\to\mu^+\mu^-$ decay has been observed at the Large Hadron Collider and the first measurement of the effective…

We investigate rare decays of tau leptons that occur via exchange of heavy on-shell neutrinos $N_j$ ($j=1,2$). These neutrinos can be either Dirac or Majorana, and are considered to be almost degenerate in mass. The decays can thus be…

In this report we discuss the main theories to understand the origin of baryon and lepton number violation in physics beyond the Standard Model. We present the theoretical predictions for rare processes such as neutrinoless double beta…

We study to what extent the unique observation of $\Lambda\Lambda$ hypernuclei by their weak decay into known $\Lambda$ hypernuclei, with lifetimes of order 10$^{-10}$ s, rules out the existence of a deeply bound doubly-strange (${\cal…

We study the semileptonic decay $\bar{B}_s \to K^{*+} \ell^-\bar\nu_\ell$, which is induced by $b\to u \ell^- \bar\nu_\ell$ transitions at the quark level. We take into account the standard model (SM) operator from $W$-boson exchange as…

The non-observation of baryon number violation suggests that the scale of baryon-number violating interactions at zero temperature is comparable to the GUT scale. However, the pertinent measurements involve hadrons made of the…

We compute $\beta$-decay half-lives of isotonic nuclear chains located at neutron shell closures $N=50$, $82$, $126$ and $184$, which are of particular importance for the $r$-process nucleosynthesis, and study the role of first-forbidden…

A search for the rare decay $B^{+} \to \bar \Lambda p \mu^{+} \mu^{-}$ is performed using proton-proton collision data recorded by the LHCb experiment at a center-of-mass energy of $\sqrt{s}= 13$ TeV, corresponding to an integrated…

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…

With the BaBar detector at the PEP-II asymmetric $B$ Factory at SLAC, we present the first search for the decays $B^0\to\ell^+\ell^-\gamma$ ($l=e, \mu$). Using a data set of 292 $fb^{-1}$ collected at the $\Upsilon(4S)$ resonance, we find…

We calculate the lifetime of the deuteron with dimension-nine quark operators that violate baryon number by two units. We construct an effective field theory for $|\Delta B|=2$ interactions that give rise to neutron-antineutron…

A search for a Higgs boson decaying into a pair of electrons or muons and a photon is described. Higgs boson decays to a Z boson and a photon (H $\to$ Z$\gamma\to\ell\ell\gamma$, $\ell =$ e or $\mu$), or to two photons, one of which has an…

The possible discovery of proton decay, neutron-antineutron oscillation, neutrinoless beta decay in low energy experiments, and exotic signals related to the violation of the baryon and lepton numbers at collider experiments will change our…

The rare decays $\eta^{(\prime)}\to\ell^+\ell^-$, $\ell\in\{e,\mu\}$, are highly suppressed in the Standard Model, both by their chirality structure and the required loop attaching the lepton line to the $\eta^{(\prime)}\to\gamma^*\gamma^*$…

Searches for the lepton flavour violating decay $\tau^-\rightarrow \mu^-\mu^+\mu^-$ and the lepton flavour and baryon number violating decays $\tau^-\rightarrow \bar{p}\mu^+\mu^-$ and $\tau^-\rightarrow p\mu^-\mu^-$ have been carried out…

Discrepancies from in-beam and in-bottle type experiments measuring the neutron lifetime are on the 4$\sigma$ standard deviation level. In a recent publication Fornal and Grinstein proposed that the puzzle could be solved if the neutron…