Evidence for Direct CP Violation in the Measurement of the Cabbibo-Kobayashi-Maskawa Angle gamma with B∓→D(*)K(*)∓ Decays

• Main Authors: Fisher, Peter H. (Contributor), Cowan, Ray Franklin (Contributor), Dujmic, Denis (Contributor), Sciolla, Gabriella (Contributor), Zhao, M. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Physics (Contributor), Massachusetts Institute of Technology. Laboratory for Nuclear Science (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2011-02-17T22:38:57Z.
• Subjects: Article
• Online Access: Get fulltext

We report the measurement of the Cabibbo-Kobayashi-Maskawa CP-violating angle gamma through a Dalitz plot analysis of neutral D-meson decays to KS0pi+pi- and KS0K+K- produced in the processes B∓→DK∓, B∓-->D*K∓ with D*-->Dpi0, Dgamma, and B∓→DK*∓ with K*∓-->KS0pi∓, using 468 million BB̅ pairs collected by the BABAR detector at the PEP-II asymmetric-energy e+e- collider at SLAC. We measure gamma=(68±14±4±3)° (modulo 180°), where the first error is statistical, the second is the experimental systematic uncertainty, and the third reflects the uncertainty in the description of the neutral D decay amplitudes. This result is inconsistent with gamma=0 (no direct CP violation) with a significance of 3.5 standard deviations.
Alfred P. Sloan Foundation
United States-Israel Binational Science Foundation
United States. Dept. of Energy
National Science Foundation (U.S.)