First observation of radiative B{sup 0}{yields}{phi}K{sup 0}{gamma} decays and measurements of their time-dependent CP violation

Journal Article · Sat Oct 01 00:00:00 EDT 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.84.071101· OSTI ID:21607727

Sahoo, H; Browder, T E; Nishimura, K; Vahsen, S E; Varner, G ^[1]; Adachi, I; Haba, J; Itoh, R; Iwasaki, Y; Nakao, M; Nishida, S; Nozaki, T; Sakai, K; Sakai, Y; Sumisawa, K; Trabelsi, K; Uno, S; Ushiroda, Y ^[2]; Asner, D M; Fast, J E ^[3]

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1. University of Hawaii, Honolulu, Hawaii 96822 (United States)
2. High Energy Accelerator Research Organization (KEK), Tsukuba (Japan)
3. Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

We report the first observation of the radiative decay B{sup 0}{yields}{phi}K{sup 0}{gamma} using a data sample of 772x10{sup 6} BB pairs collected at the {Upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider. We observe a signal of 37{+-}8 events with a significance of 5.4 standard deviations including systematic uncertainties. The measured branching fraction is B(B{sup 0}{yields}{phi}K{sup 0}{gamma})=(2.74{+-}0.60{+-}0.32)x10{sup -6}, where the uncertainties are statistical and systematic, respectively. We also report the first measurements of time-dependent CP-violation parameters: S{sub {phi}}K{sub S}{sup 0}{sub {gamma}}=+0.74{sub -1.05}{sup +0.72}(stat){sub -0.24}{sup +0.10}(syst) and A{sub {phi}}K{sub S}{sup 0}{sub {gamma}}=+0.35{+-}0.58(stat){sub -0.10}{sup +0.23}(syst). Furthermore, we measure B(B{sup +}{yields}{phi}K{sup +}{gamma})=(2.48{+-}0.30{+-}0.24)x10{sup -6}, A{sub CP}=-0.03{+-}0.11{+-}0.08, and find that the signal is concentrated in the M{sub {phi}}K mass region near threshold.

• OSTI ID: 21607727
• Journal Information: Physical Review. D, Particles Fields, Vol. 84, Issue 7; Other Information: DOI: 10.1103/PhysRevD.84.071101; (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
B NEUTRAL MESONS
BRANCHING RATIO
CP INVARIANCE
ELECTRON-POSITRON COLLISIONS
GAMMA DECAY
GAMMA RADIATION
KAONS NEUTRAL
KAONS PLUS
KEK LINAC
MASS
PHI MESONS
POSITRONS
RADIATIVE DECAY
RESONANCE
TIME DEPENDENCE
VECTOR MESONS
ACCELERATORS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
B MESONS
BEAUTY MESONS
BEAUTY PARTICLES
BOSONS
COLLISIONS
DECAY
DIMENSIONLESS NUMBERS
ELECTROMAGNETIC RADIATION
ELECTRON COLLISIONS
ELEMENTARY PARTICLES
FERMIONS
HADRONS
INVARIANCE PRINCIPLES
IONIZING RADIATIONS
KAONS
LEPTONS
LINEAR ACCELERATORS
MATTER
MESONS
NUCLEAR DECAY
PARTICLE DECAY
POSITRON COLLISIONS
PSEUDOSCALAR MESONS
RADIATIONS
STRANGE MESONS
STRANGE PARTICLES