Knockout reaction induced by ^6He at 61.2 MeV/u

A knockout reaction induced by ^6He at 61.2 MeV/u was carried out at the HIRFL-RIBLL ra- dioactive beam line. The α core fragments at forward angles were detected in coincidence with the recoiled protons at large angles. From this coincident measurement the valence nucleon knockout mechanism and the core knockout mechanism can be separated according to the polar angle correlation between the core fragments and the recoiled protons. It is demonstrated that, when reconstructing the resonant state of a weakly bound nucleus, the contamination resulting from the core knockout mechanism should be eliminated in order to obtain the correct structure information.

Analysis of B_s→Φμ^+μ^- decay within supersymmetry

Motivated by the first measurement on B（Bs→ Ф μ^＋ μ^-by the CDF Collaboration, we study the supersymmetric effects in semi-leptonic Bs→ Ф μ^＋ μ^-ecay. In our evaluations, we analyze the dependences of the dimuon invariant mass spectrum and the forward-backward asymmetry on relevant supersymmetric couplings in the MSSM with and without R-parity. The analyses show that the new experimental upper limits of B（Bs→ Ф μ^＋ μ^-from the LHCb Collaboration could further improve the bounds on sneutrino exchange couplings and （δ^u LL）23 as well as （δ^d LL,RR）23 mass insertion couplings. In addition, within the allowed ranges of relevant couplings under the constraints from B（Bs→ Ф μ^＋ μ^- B（B → K^（＊） μ^＋ μ^-and B（Bs → μ^＋ μ^-, the dimuon forward-backward asymmetry and the differential dimuon forward-backward asymmetry of Bs→Ф μ^＋ μ^-re highly sensitive to the squark exchange contribution and the （ LL）23 mass insertion contribution. The results obtained in this work will be very useful in searching for supersymmetric signals at the LHC.