arXiv subjects

Xiang-Dong Gao

Publications and source records attributed to Xiang-Dong Gao.

2 recordsLinked to original sources

arXiv2013

Study the Forward-Backward Asymmetry of the Top Quark Production in the Randall-Sundrum Model with an Extension of Strong Interaction

The large forward-backward asymmetry of the top quark pair production measured by the hadron colliders shed light on new physics signals beyond the Standard Model. In the Randall-Sundrum model with an additional SU(3) group in the strong sector, we compare the total cross section and forward-backward asymmetry of the top quark pair production with the newest data obtained by the CDF and the D0 collaborations. Our numerical analysis shows that the parameter $c_q \gtrsim 0.5$, $c_t \sim -0.6\sim-0.8$, $\tanϕ\gtrsim 20$ or $\tanϕ\leq 1/20$ and the first excitation of axial gluon with a mass about $5 \thicksim 6 \mathrm{TeV}$ can accommodate this large anomaly without violating other experimental constraints.

hep-ph↗

arXiv2013

Constraints on the R-parity violating couplings using the newest measurement of the decay $B_s^0 \rightarrow μ^+ μ^-$

Recently, the LHCb collaboration reported the first evidence for the decay $B_s^0 \rightarrow μ^+ μ^-$. A branching ratio of $\mathcal{B}(B_s^0 \rightarrow μ^+ μ^-) = (3.2^{+1.5}_{-1.2}) \times 10^{-9}$ is given. Using the newest data, and together with the most precise predictions of the Standard Model contributions to the decay, we derive the constraints on the combinations of the R-parity violating parameters. Our results are several orders of magnitudes stronger than the constraints in the previous literature. We also update the constraints on the relevant parameters using the upper limit of $\mathcal{B}(B_d^0 \rightarrow μ^+ μ^-)$.

hep-ph↗