Explaining B \to K pi anomaly with non-universal Z' boson

We study the effect of non-universal $Z'$ boson in the decay modes $B \to K \pi$. In the standard model these modes receive dominant contributions from $b \to s$ QCD penguins. Therefore, in this limit one expects $S_{\pi^0 K^0} \approx \sin 2 \beta$, $A_{\pi^0 K^0} \approx 0$ and $A_{\pi^0 K^-} \approx A_{\pi^+ K^-}$. The corrections due to the presence of small non-penguin contributions is found to yield $S_{\pi^0 K^0} > \sin 2 \beta$ and $\Delta A_{CP}(K \pi) \simeq 2.5$. However, the measured value of $S_{\pi^0 K^0}$ is less than $\sin 2 \beta$ and $\Delta A_{CP}(K \pi) \simeq 15$. We show the model with a non-universal $Z'$ boson can successfully explain these anomalies.Comment: 11 pages, 3 figure

Implications of lepton nonuniversality in the beauty sector

The phenomenon of CP violation in the standard model (SM) framework and the decay dynamics have been established from the data obtained from the B factories and so far we have not seen anything new. Nevertheless, there have been instances of deviations in many measured observables in the flavor sector, as far as the data and predictions are concerned. Here we will mention some deviations obtained in measurements related to lepton universality, as seen from the data, and try to understand their implications. To accommodate the observed data we will consider a leptoquark model, which seems to be one interesting model beyond the SM.Comment: 6 pages, 4 figures, talk given at BEACH 2016, George Mason University, Fairfax, Virginia, USA, June 201

Probing new physics in B -> f_0(980) K decays

We study the hadronic decay modes $B^{\pm(0)} \to f_0(980) K^{\pm(0)}$, involving a scalar and a pseudoscalar meson in the final state. These decay modes are dominated by the loop induced $b \to s \bar q q(q=s,u,d)$ penguins along with a small $b \to u$ tree level transition (for $B^+ \to f_0 K^+$) and annihilation diagrams. Therefore, the standard model expectation of direct CP violation is negligibly small and the mixing induced CP violation parameter in the mode $B^0 \to f_0 K_S$ is expected to give the same value of $\sin(2\beta)$, as extracted from $B^0 \to J/\psi K_S$ but with opposite sign. Using the generalized factorization approach we find the direct CP violation in the decay mode $B^+ \to f_0 K^+$ to be of the order of few percent. We then study the effect of the R-parity violating supersymmetric model and show that the direct CP violating asymmetry in $B^+ \to f_0(980) K^+$ could be as large as $\sim 80$ and the mixing induced CP asymmetry in $B^0 \to f_0 K_S$ (i.e., $-S_{f_0 K_S}$) could deviate significantly from that of $\sin(2 \beta)_{J/\psi K_S}$.Comment: 18 pages, 5 figures, version to appear in Phys. Rev.

Analysis of direct CP violation in B−→D0Ds−,D0D−B^- \to D^0 D_s^-, D^0 D^- decays

We investigate the possibility of observing the direct CP violation in the decay modes $B^- \to D^0 D_s^-$ and $D^0 D^-$ within the Standard Model. Including the contributions arising from the tree, annihilation, QCD as well as electroweak penguins with both time- and space-like components, we find that the direct CP asymmetry in $B^- \to D^0 D_s^-$ is very small $\sim 0.2$ % but in $B^- \to D^0 D^-$ decay it can be as large as 4%. Approximately $10^7$ charged $B$ mesons are required to experimentally observe the CP asymmetry parameter for the later case. Since this is easily accessible with the currently running B factories, the decay mode $B^- \to D^0 D^-$ may be pursued to look for CP violation.Comment: Latex, 14 page

The Bonded Labor System in Nepal: Exploring Halia and Kamaiya Children’s Life-worlds

Nepal is believed to have thousands of bonded laborers under the so-called haliya and kamaiya systems. The latter was outlawed in 2000 and the former in 2008, following a widespread campaign by local organisations, including the bonded laborers themselves. While state intervention has reportedly discouraged adults from forging an annual haliya or kamaiya contract, even the so-called “systematic rehabilitation” of “freed” kamaiya families has not been entirely successful in offering long-term livelihood alternatives. As a result, patchy reports suggest that children are increasingly taking the jobs done by their parents or elders. This study, which focuses on Musahar and Tharu communities, explores the perspective of such bonded children on their daily life-worlds