Dark matter contribution to $b \to s \mu^+ \mu^-$ anomaly in local $U(1)_{L_\mu-L_\tau}$ model

by Dr Seungwon Baek (KIAS)

Wednesday 20 Sept 2017, 15:00 → 16:00 Asia/Seoul

CTPU Seminar Room (KAIST Munji Campus)

We propose a local $U(1)_{L_mu-L_tau}$ model to explain $b to s mu^+ mu^-$ anomaly observed at the LHCb and Belle experiments. The model also has a natural dark matter candidate. We introduce colored $SU(2)_L$-doublet scalar $widetilde{q}$ to mediate $b to s$ transition at one-loop level. The $U(1)_{L_mu-L_tau}$ is spontaneously broken by the scalar $S$. All the new particles are charged under $U(1)_{L_mu-L_tau}$. We can obtain $C_9^{mu,{rm NP}} sim -1$ ! to explain the $b to smu^+mu^-$ anomaly and explain the correct dark matter relic density of the universe, $Omega_{rm DM} h^2 approx 0.12$ while evading constraints from other FCNC processes such as $b to s gamma$ or $B_s-overline{B}_s$ mixing. Our model can be tested by searching for new colored scalar at the LHC and $B to K^* nu overline{nu}$ process at Belle-II.