Some Selected Physics at BESIII and New Physics

Some Selected Physics at BESIII and New Physics Searches Xian-Wei Kang USTC, Hefei , May 25 -26, 2019 http: //cicpi. ustc. edu. cn/indico/conference. Display. py? ovw=True&conf. Id=1857

n CP asymmetry in D->VV X. W. Kang, H. B. Li, PLB 2010 n CP asymmetry in decay X. W. Kang, H. B. Li, G. R. Lu, A. Datta, IJMPA 2010 n CP asymmetry in strange baryon I. I. Bigi, X. W. Kang, H. B. Li, CPC 2018 n Prospects for CP and P violation in charm baryon at STCF. X. D. Shi, X. W. Kang, Bigi, H. P. Peng… ar. Xiv: 1904. 12415 Point out different path to find CPV, maybe tiny, worth to do Sensitivities studied by MC samples based on the performance of data Still have no reliable way to estimate the central values See talk given by Bo Zheng.

Outline •

Elastic part and annihilation

Chiral potentials No unknown parameters in those contributions: pion-nucleon coupling constant, pion decay constant

Contact terms u Contact terms treat ü short-range force, where effective field theory fails ü (strong) annihilation effect u Contact terms are parametrized as polynomials, power expansion by momentum u The parameters are fixed by fitting to the partial wave amplitudes. [Zhou and Timmermans, PRC 86, 044003 (2012)]

Uncoupled-channel case

Coupled-channel case

Relation with the recent measurements n BESIII collaboration, “Polarization and Entanglement in Baryon -Antibaryon Pair Production in Electron-Positron Annihilation”, Nature Physics 2019 n BESIII collaboration, “Complete measurement of Λ electromagnetic form factors”, ar. Xiv: 1903. 09421 Phase difference between GE and GM The polarization ΔΦ = 42. 4 ± 0. 6 ± 0. 5°

Relation with the New Physics n Workshop on New Physics Searches at BESIII n New Physics refers to physics beyond Standard Model üLarge deviations from SM, we should focus on the precision of SM prediction üDifferent New Physics models as input to predict

Kinematics

Decay rate expressed by kinematic factors and form factors. Dynamical information is embedded in form factors.

Dynamics Taking into account the major intermediate state contributions from η, η′, f 0(980) and X(1835)

• A crude but first-time prediction < 10 -7 Challenge all the measurements given the statistics of Ds data sample Agrees with the current experiment limit, the work is ongoing

Semiletonic D and Ds decay n Precise extraction of CKM matrix elements n Clean final state interaction n Test various theoretical model calculation n Examine the property of axial-vector and scalar mesons