Study of K{sup -}{yields}{pi}{sup 0}e{sup -}{nu}-bar{sub e}{gamma} decay with ISTRA+ setup

Journal Article · Sun Apr 15 04:00:00 EDT 2007 · Physics of Atomic Nuclei

DOI:https://doi.org/10.1134/S1063778807040114· OSTI ID:21075896

Akimenko, S A ^[1]; Britvich, G I; Datsko, K V ^[1]; Duk, V A ^[2]; Filin, A P ^[1]; Gushchin, E N ^[2]; Inyakin, A V; Khmelnikov, V A; Konstantinov, A S; Konstantinov, V F; Korolkov, I Yu ^[1]; Laptev, S V; Lebedev, V A ^[2]; Leontiev, V M ^[1]; Mazurov, A E ^[2]; Novikov, V P; Obraztsov, V F; Polyakov, V A ^[1]; Polyarush, A Yu ^[2]

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1. Institute for High Energy Physics (Russian Federation)
2. Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

Results of study of the K{sup -}{yields}{pi}{sup 0}e{sup -}{nu}-bar{gamma} decay at the ISTRA+ setup are presented. We observed 4476 events of this decay. The branching ratio is found to be R=(Br(K{sup -}{yields}{pi}{sup 0}e{sup -}{nu}-bar{sub e}{gamma}))/(Br(K{sup -}{yields}{pi}{sup 0}e{sup -}{nu}-bar{sub e})) (1.81{+-}0.03(stat.){+-}0.07(syst.)) x 10{sup -2} for E*{sub {gamma}} > 10 MeV and {theta}*{sub e{gamma}} > 10{sup o}. For comparison with the previous experiment the branching ratio with cuts E*{sub {gamma}} > 10 MeV, 0.6 < cos {theta}*{sub e{gamma}} < 0.9 is calculated: R (Br(K{sup -}{yields}{pi}{sup 0}e{sup -}{nu}-bar{sub e}{gamma}))/(Br(K{sup -}{yields}{pi}{sup 0}e{sup -}{nu}-bar{sub e})) (0.47{+-}0.02(stat.) {+-} 0.03(syst.)) x 10{sup -2}. For the cuts E*{sub {gamma}} > 30 MeV and {theta}*{sub e{gamma}} > 20{sup o}, used in most theoretical papers, Br (3.06 {+-} 0.09(stat.) {+-} 0.14(syst.)) x 10{sup -4}. For the asymmetry we get A{sub {xi}} = -0.015 {+-} 0.021. At present it is the best estimate of this asymmetry.

• OSTI ID: 21075896
• Journal Information: Physics of Atomic Nuclei, Journal Name: Physics of Atomic Nuclei Journal Issue: 4 Vol. 70; ISSN 1063-7788; ISSN PANUEO
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
BRANCHING RATIO
COMPARATIVE EVALUATIONS
ELECTRON ANTINEUTRINOS
ELECTRONS
GAMMA RADIATION
KAONS MINUS
MEV RANGE
PARTICLE DECAY
PIONS NEUTRAL