We present a unified explanation for the B-decay anomalies in R D ( * ) and RK together with the anomalous muon magnetic moment, consistent with the constraints from the current measurements of leptonic decay rates ands mixings, within the framework of a minimal left-right symmetric gauge theory motivated by one of the low-energy subgroups of E6 naturally accommodating leptoquarks.

The LHCb has measured the ratios of B → K * µ + µ − to B → K * e + e − branching fractions in two dilepton invariant mass squared bins, which deviate from the Standard Model predictions by approximately 2.5σ. These new measurements strengthen the hint of lepton flavor universality breaking which was observed earlier in B → K + − decays. In this work we explore the possibility of explaining these anomalies within the framework of R-parity violating interactions. In this framework, b → s + − transitions are generated through tree and one loop diagrams involving exchange of down-type right-handed squarks, up-type left-handed squarks and left-handed sneutrinos. We find that the tree level contributions are not enough to explain the anomalies, but at one loop, simultaneous explanation of the deviations in B → K * + − and B → K + − is feasible for a parameter space of the Yukawa couplings that is consistent with the bounds coming from B → K ( * ) νν and D 0 → µ + µ − decays and Bs −Bs mixing.

We give an assessment of the three approaches, undertaken by the D∅ experiment, to probe CP violation in Bs mixing without measurement of Bs-Bs oscillations or tagging: dimuon charge asymmetry ASL, untagged single muon charge asymmetry A s SL , and lifetime difference in untagged Bs → J/ψφ decay. The latter two approaches provide an alternative avenue, if not crosscheck, to the usual mixing-decay interference study in modes such as Bs → J/ψφ. Prospects at the Tevatron, LHC and (Super) B factories are discussed. PACS numbers: 13.25.Hw, 13.20.-v, 12.60.-i B s -B s mixing has recently been measured by the CDF experiment [1]. The result is consistent with the Standard Model (SM) expectation, albeit slightly on the low side. This suggests that New Physics (NP) corrections are mild, unless the CP violation (CPV) phase in M 12 , φ s ≡ 2Φ Bs , is greatly different from SM expectation. Thus, the focus has shifted to measurement of φ s . The standard approach is via mixing-decay interference, or the so-called time-dependent CPV studies, such as via the B s → J/ψφ mode [2], which is analogous to B d → J/ψK S studies at the B factories. This approach depends on the ability of resolving B s -B s oscillations, tagging the B s vsB s flavor, as well as having a large data sample of B s → J/ψφ.An alternative approach does not rely on measuring the very rapid B s -B s oscillations, oftentimes forsaking even tagging. The D∅ experiment has recently conducted a three-pronged approach along this line: the dimuon charge asymmetry A SL (self-tagged) [3], the untagged single muon charge asymmetry A s SL [4], and a measurement of the lifetime difference in untagged B s → J/ψφ decay, but keeping the CPV phase φ s free [5]. The three measurements offer independent probes of CPV in the B s system, although A SL also incorporates the effect from B d in the Tevatron environment. The experimental results, however, are not so easy to grasp. While there are hints for large deviations from SM, at the same time there are some conflicts.In this note we comment on the merits and demerits of the three different measurements, and assess future prospects at the Tevatron, LHC, and the (Super)B factories. Part of our motivation is whether one could have near maximal CPV in A s SL . For this purpose, we take the 4 generation model recently studied in [6,7] as our NP scenario, which we will show nearly saturates the possible enhancements from SM in A s SL . The same sign dimuon asymmetry

We calculate the zeroes of angular observables P 4 and P 5 of 4 -body angular distribution of B → K * (→ Kπ)l + l − where LHCb, in its analysis of form factor independent angular observables, has found deviations from standard model predictions in one of the q 2 bins. In the large recoil region, we obtain relations between the zeroes of P 4 , P 5 and the zero of forward-backward asymmetry of lepton pair. These relations, in the considered region, are independent of hadronic uncertainties and depend only on Wilson coefficients. We also construct a new observable, O L,R T, whose zero in the standard model coincides with the zero of forward-backward asymmetry but in presence of new physics contributions will show different behavior. Moreover, the profile of the new observable, even within the standard model, is very different from the forward backward asymmetry. We point out that precise measurements of these zeroes in near future would provide crucial test of the standard model and would be useful in distinguishing between different possible new physics contributions to Wilson coefficients.

In this paper we study the polarization asymmetries of the final state lepton in the radiative dileptonic decay of B meson (Bs → ℓ + ℓ − γ ) in the framework of Minimal Supersymmetric Standard Model (MSSM) and various other unified models within the framework of MSSM e.g. mSUGRA, SUGRA (where condition of universality of scalar masses is relaxed) etc. Lepton polarization, in addition of having a longitudinal component (PL ), can have two other components, PT and PN , lying in and perpendicular to the decay plane, which are proportional to m ℓ and hence are significant for final state being µ + µ − or τ + τ − . We analyse the dependence of these polarization asymmetries on the parameters of the various models.

Within the framework of Standard Model, the exclusive decay mode B → πγγ is studied. Although the usual short distance contribution is small compared to the similar B → Kγγ mode, the process offers the possibility of studying the CP violation, a feature absent in the B → K counterpart.

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If neutrinos are to be identified with the primary source of ultrahigh energy cosmic rays ͑UHECR͒, their interaction on relic neutrinos is of great importance in understanding their long intergalactic journey. In theories with large compact dimensions, the exchange of a tower of massive spin-2 gravitons ͑Kaluza-Klein excitations͒ gives an extra contribution to → f f and ␥␥ processes along with the opening of a new channel for the neutrinos to annihilate with the relic cosmic neutrino background →G kk to produce bulk gravitons in the extra dimensions. This will affect their attenuation. We compute the contribution of these Kaluza-Klein excitations to the above processes and find that for parameters of the theory constrained by supernova cooling, the contribution does indeed become the dominant contribution above ͱsӍ300 GeV.