Title: Semitauonic B decays: a key window for new Physics 
Speaker: Guy Wormser（LAL） 
Moderator: Prof. Shen Xiaoyan
Time:15:00, March 13, 2017
Place: Room C305, IHEP Main Building 

Abstract: 
Semitauonic decays are one of the most abundant channels in B hadron decays and are predicted very precisely in the Standard Model. They are in addition very sensitive to many new physics phenomena, in particular to the presence of charged Higgs bosons and are therefore an ideal platform to search for new physics effects. A new very powerful method to measure this reaction will be presented, using the hadronic decay of the tau lepton in 3 pions in LHCb data. To fully exploit this new gateway to BSM physics, more detailed information than presently available regarding inclusive D0, D+ and Ds decays into 3 pions is required. The BES-III data set can be extremely valuable in this regard. 

About the speaker:
Guy Wormser is a senior researcher at Laboratory of Accélérateur Linéaire of Orsay, which he joined 40 years ago. He worked in many HEP experiments at CERN and overseas. After his PhD degree obtained in 1984 on the study of prompt photo production (NA14 experiment et CERN), the first one to confirm the fractional nature of the quarks electric charge, he searched for new physics at e+e- colliders: MarkII at SLC and DELPHI at CERN. HE then specialized in flavor physics, being one of the early promoters of the asymmetric B factories and of the BABAR experiment at SLAC, in which he led the French community. He became involved in research management, deputy director of IN2P3, the French national funding agency for 1999 to 2003, period during which he played a very active role in promoting grid computing and what will become the WLCG collaboration. From 2005 to 2011 , he was named head of the LAL laboratory, period during which he promoted the interest of very high precision B physics as a key avenue towards new physics, in the framework of the SuperB project , as a deputy project leader. He then joined the LHCb experiment at CERN, to pursue this quest.