arXiv subjects

Deshpande

Publications and source records attributed to Deshpande.

4 recordsLinked to original sources

arXiv1999

Electroweak Penguins, Final State Interaction Phases and CP Violatioin in $B\to K π$ Decays

The recently observed $B^-\to K^- π^0$, $\bar K^0 π^-$ and $\bar B^0 \to K^- π^+$ decay modes appear to have nearly equal branching ratios. This suggests that tree and electroweak penguins play an important role, and inclusion of the latter improves agreement between factorization calculation and experimental data. The value $γ$ in the range $90^\circle - 130^\circle$ and $220^\circle - 260^\circle$ is favored, while the $\bar B^0 \to \bar K^0 π^0$ rate is suppressed. Direct CP violation for $B\to K π$ modes can be large if final state interaction phases are large.

hep-ph↗

arXiv1995

The Nonresonant Cabibbo Suppressed Decay $B^\pm\to π^+π^-π^\pm$ and Signal for CP Violation

We consider various contributions to the nonresonant decay $B^\pm\rightarrow π^+π^-π^\pm$, both of the long-distance and short-distance types with the former providing for most of the branching ratio, predicted to be $BR(B^\pm\rightarrow π^+π^-π^\pm) = (1.5 - 8.4 )\times 10^{-5}$. We also discuss an application to CP violation resulting from the interference of that nonresonant background (with $m(π^+π^-)\approx 3.4$ GeV) and $B^\pm\rightarrow χ_{c0} π^\pm$ followed by $χ_{c0}\rightarrow π^+π^-$. The resulting value of the partial rate asymmetry is $(0.40\sim 0.48)\mbox{sin}γ$, where $γ= \mbox{arg}(V_{ub}^*)$.

hep-ph↗

arXiv1994

Unique Signature of Electroweak Penguin In Pure Hadronic $B$ Decays

We study elelctroweak penguin contributions in pure hadronic $B$ decays in the Standard and two-Higgs-doublet models. We find that in $B_s\rightarrow π^0 (η\;, ϕ)$ and $B_s\rightarrow ρ^0 (η\;, ϕ)$ decays, the electroweak penguin contributions dominate over all other contribuitons. These processes provide unique signatures of electroweak penguin in pure hadronic processes. These modes could be in measureable range of future $B$ facilities.

hep-ph↗

arXiv1994

Amplitude Zeros in Radiative Decays of Scalar Particles

We study amplitude zeros in radiative decay processes with a photon or a gluon emission of all possible scalar particles(e.g. scalar leptoquarks) which may interact with the usual fermions in models beyond the standard model. For the decays with a photon emission, the amplitudes clearly exhibit the factorization property and the differential decay rates vanish at specific values of a certain variable which are determined only by the electric charges of the particles involved and independent of the particle masses and the various couplings. For the decays with a gluon emission, even though the zeros are washed away, the differential decay rates still have distinct minima. The branching ratios as a function of leptoquark masses are presented for the scalar leptoquark decays. We also comment on the decays of vector particles into two fermions and a photon.

hep-ph↗