Observation of the radiative kaon decay K{sup -} {sup {yields}} {mu}{sup -}{pi}{sup 0}{gamma}{nu}

Journal Article · Mon Jan 15 04:00:00 EST 2007 · Physics of Atomic Nuclei

DOI:https://doi.org/10.1134/S1063778807010048· OSTI ID:21075972

Akimenko, S A; Britvich, G I; Datsko, K V; Filin, A P; Inyakin, A V; Khmelnikov, V A; Konstantinov, A S; Korolkov, I Ya; Leontiev, V M; Novikov, V P; Obraztsov, V F; Polyakov, V A; Romanovsky, V I; Shelikhov, V I; Uvarov, V A; Yushchenko, O P; Bolotov, V N; Laptev, S V; Duk, V A ^[1]

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1. Institute for High Energy Physics (Russian Federation)

Using data collected with the ISTRA+ spectrometer during the 2001 run of the U-70 proton synchrotron in Protvino, the first observation of the radiative kaon decay K{sup -} {sup {yields}} {mu}{sup -}{pi}{sup 0}{gamma}{nu} is reported. The ratio Br(K{sub {mu}}{sub 3{gamma}}, 5 < E*{sub {gamma}} < 30 MeV)/Br(K{sub {mu}}{sub 3}) is found to be [0.270 {+-} 0.029(stat.) {+-} 0.026(syst.)]% and the ratio Br(K{sub {mu}}{sub 3{gamma}}, 30 < E*{sub {gamma}} < 60 MeV)/Br(K{sub {mu}}{sub 3}) = [0.0448 {+-} 0.0068(stat.) {+-} 0.0099(syst.)]%. These ratios are consistent with the theoretical predictions 0.21 and 0.047%, respectively. The measured angular distribution asymmetry for the region 5 < E*{sub {gamma}} < 30 MeV, A(cos {theta}*{sub {mu}}{sub {gamma}}) = 0.093 {+-} 0.141, is two standard deviations away from the theoretical prediction of 0.354. The measured asymmetry in the T-odd variable {xi} = p{sub {gamma}} . (p{sub {mu}} x p{sub {pi}})/m{sub K}{sup 3} is -0.03 {+-} 0.13.

• OSTI ID: 21075972
• Journal Information: Physics of Atomic Nuclei, Journal Name: Physics of Atomic Nuclei Journal Issue: 1 Vol. 70; ISSN 1063-7788; ISSN PANUEO
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR DISTRIBUTION
ASYMMETRY
FORECASTING
GAMMA RADIATION
KAONS
KAONS MINUS
MEV RANGE
MUONS MINUS
NEUTRINOS
PARTICLE DECAY
PIONS NEUTRAL
PROTONS
RADIATIVE DECAY
SPECTROMETERS
STANDARDS
SYNCHROTRONS