分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: As a top quark factory, the LHC can test the new physics models used to explain the top quark forward-backward asymmetry A^t_FB measured at the Tevatron. In this work we perform a comparative study for two such models: the W'-model and the color triplet d
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: The excess of top quark forward-backward asymmetry (AtFBAFBtA^t_{FB}) reported by the Tevatron and the enhancement of the Higgs decay to diphoton observed by the LHC may point to a same origin of new physics. In this note we examined such anomalies in the
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: In a topcolor-assisted technicolor model (TC2) with large FCNC top quark couplings, we study its correlated contributions to the top quark forward-backward asymmetry (AF B ) at the Tevatron, the top charge asymmetry (AC) and the triple-top production at the LHC. Under current constraints on the top quark from the LHC and Tevatron (such as the total and differential production rates), we scan the parameter space of such a TC2 model. We find that in the allowed parameter space the TC2 model can explain the Tevatron measured AFB at 2σ level, but meanwhile significantly enhance AC at the LHC. Such enhanced AC, albeit currently allowed by the LHC measurement at 2σ level, will serve as a test of TC2 with the improvement of measurement precision at the LHC. Then with all the constraints (including the requirement to explain AF B at 2σ level and satisfying the current LHC measurement of AC at 2σ level), we find that the TC2 model can induce sizable triple-top production at the 14 TeV LHC (the production rate can maximally reach 16 pb). Due to the low SM backgrounds, the triple-top production can also be a good probe for TC2 model, complementary to AC.
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: In order to explain the Tevatron anomaly of the top quark forward-backward asymmetry AtFBAFBtA_{FB}^t in the left-right twin Higgs model, we choose to give up the lightest neutral particle of h^h^\hat{h} field as a stable dark matter candidate. Then a new
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2016-12-28
摘要: In the next-to-minimal supersymmetric model (NMSSM) a light CP-odd Higgs boson is so far allowed by current experiments, which, together with a large tanβtan?β\tan\beta, may greatly enhance the rare dileptonic decays B\to X_s l^+ l^- and B_s\to l^+ l^- \g
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: The anomaly of the top quark forward-backward asymmetry AtFBAFBtA^t_{FB} observed at the Tevatron can be explained by the t-channel exchange of a neutral gauge boson (Z') which has sizable flavor changing coupling for top and up quarks. This gauge boson c