文档介绍：- CNS1 Apr 2005 1 New results from BaBar Summary of contributions to Winter Conferences Gianluca Cavoto Universita ’ di Roma “ La Sapienza ” and INFN Roma - CNS1 Apr 2005 2 Outline ??? cb ubV V cb tdV VB????K s,K sK sK s D * ???D 0 K, DK s |V ub | (x 3!), b?s?B???+ new physics studies ? K s? 0??????? X(3872) Tree Penguins New Physics Exotic lands … - CNS1 Apr 2005 3 Data Sample 244 fb -1 Run1-4 data (if not otherwise specified) 244 fb -1 Run1-4 data (if not otherwise specified) Publish Summer preliminary results. A lot of interesting new ing out of BaBar (cannot cover everything) - CNS1 Apr 2005 4 Measurements of | V ub| Including b ?s? studies and search for B ??? ub cbVV - CNS1 Apr 2005 5 Physics on the recoil The high luminosity and the high number of fully reconstructed B ’ s opens a new world in B physics: Fully reconstruct one of the Bs and study the remaining of the event ? close the kinematics , missing energy reconstruction Semileptonic D (*) l(n?) 5K/ fb -1 Hadronic D (*) X 3K/ fb -1 efficiency purity Tag types X= n?+m ? 0+ pK + qK s - CNS1 Apr 2005 6 |V ub | and semileptonic B decays ?|V ub | determines the left side of the UT ? Uncertainty on | V ub | is dominated by theory errors ? Measurements with different methods important ? Exclusive B→???v,??v, ??v, …? Better S/B , (with B-tagging) ? Theory (LCSR, LQCD, etc.) must predict form factors ? Theory error hard to quantify ? Inclusive B→X u?v ? Use difference in kinematics to separate u? v from c?v ? Extrapolation to full rate need theory for efficiency ? Theory (OPE, SCET) must predict signal spectra ? Current theory error 10-15% of | V ub| Br as a function of q 2 Br as a function of q 2B?s? spectrum B?s? spectrum - CNS1 Apr 2005 7 Semileptonic tags : ?+l???? 0l? PRELIMINARY ? B =angle between the B momentum and the plane defined by the D (*)? and ?? momenta fully reconstruct one B in D (*)l? and