We report the first observation of the radiative charm decay D0→ρ0γ and the first search for CP violation in decays D0→ρ0γ, φγ, and K̄∗0(892)γ, using a data sample of 943 fb-1 collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The branching fraction is measured to be B(D0→ρ0γ)=(1.77±0.30±0.07)×10-5, where the first uncertainty is statistical and the second is systematic. The obtained CP asymmetries ACP(D0→ρ0γ)=+0.056±0.152±0.006, ACP(D0→φγ)=-0.094±0.066±0.001, and ACP(D0→K̄∗0γ)=-0.003±0.020±0.000 are consistent with no CP violation. We also present an improved measurement of the branching fractions B(D0→φγ)=(2.76±0.19±0.10)×10-5 and B(D0→K̄∗0γ)=(4.66±0.21±0.21)×10-4.
Bibliographical noteFunding Information:
We acknowledge support from the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan, the Japan Society for the Promotion of Science (JSPS), and the Tau-Lepton Physics Research Center of Nagoya University; the Australian Research Council; Austrian Science Fund; the National Natural Science Foundation of China; the Chinese Academy of Science Center for Excellence in Particle Physics; the Ministry of Education, Youth and Sports of the Czech Republic; the Carl Zeiss Foundation, the Deutsche Forschungsgemeinschaft, the Excellence Cluster Universe, and the VolkswagenStiftung; the Department of Science and Technology of India; the Istituto Nazionale di Fisica Nucleare of Italy; the WCU program of the Ministry of Education, National Research Foundation (NRF) of Korea; the Brain Korea 21-Plus program and Radiation Science Research Institute; the Polish Ministry of Science and Higher Education and the National Science Center; the Ministry of Education and Science of the Russian Federation and the Russian Foundation for Basic Research; the Slovenian Research Agency; Ikerbasque, Basque Foundation for Science and the Euskal Herriko Unibertsitatea (UPV/EHU) (Spain); the Swiss National Science Foundation; the Ministry of Education and the Ministry of Science and Technology of Taiwan; and DOE and NSF (USA).
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)