Differential cross section and photon-beam asymmetry for the gamma n --> K+ Sigma- reaction at E gamma = 1.5-2.4 GeV.
Differential cross sections and photon-beam asymmetries have been measured for the gamma n --> K+ Sigma- and gamma p --> K+Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of E gamma = 1.5-2.4 GeV at 0.6 < cos ThetacmK< 1. The cross section ratio of sigma K+ Sigma-/sigma K+ Sigma0, expected to be 2 on the basis of the isospin 1/2 exchange, is found to be close to 1. For the K+ Sigma- reaction, large positive asymmetries are observed, indicating the dominance of K* exchange. The large difference between the asymmetries for the K+ Sigma- and K+ Sigma0 reactions cannot be explained by simple theoretical considerations based on Regge model calculations.
Kohri
H
H
Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan.
Ahn
D S
DS
Ahn
J K
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Akimune
H
H
Asano
Y
Y
Chang
W C
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Date'
S
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Ejiri
H
H
Fukui
S
S
Fujimura
H
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Fujiwara
M
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Hasegawa
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Hicks
K
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Hotta
T
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Imai
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Ishikawa
T
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Iwata
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Kawai
H
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Kim
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Kino
K
K
Kumagai
N
N
Makino
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Mart
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Matsuda
T
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Matsumura
T
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Matsuoka
N
N
Mibe
T
T
Miyabe
M
M
Miyachi
Y
Y
Morita
M
M
Muramatsu
N
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Nakano
T
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Niiyama
M
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Nomachi
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Ohashi
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Ohkuma
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Ooba
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Oshuev
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Rangacharyulu
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Sakaguchi
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Sasaki
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Shagin
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Shiino
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Shimizu
A
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Shimizu
H
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Sugaya
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Sumihama
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Toi
Y
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Toyokawa
H
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Wakai
A
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Wang
C W
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Wang
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Yonehara
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Yorita
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Yoshimura
M
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Yosoi
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Zegers
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