Near-threshold diffractive psi-meson photoproduction from the proton.
Photoproduction of a phi meson on protons was studied by means of linearly polarized photons at forward angles in the low-energy region from threshold to Egamma = 2.37 GeV. The differential cross sections at t = -|t|min do not increase smoothly as Egamma increases but show a local maximum at around 2.0 GeV. The angular distributions demonstrate that phi mesons are photoproduced predominantly by helicity-conserving processes, and the local maximum is not likely due to unnatural-parity processes.
Mibe
T
T
Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan.
Chang
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Nakano
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Ahn
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Ahn
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Akimune
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Asano
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Daté
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Ejiri
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Fujimura
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Fujiwara
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Hicks
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Hotta
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Imai
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Ishikawa
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Iwata
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Kim
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Kino
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Kohri
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Kumagai
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Makino
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Matsuda
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Matsumura
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Matsuoka
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Miwa
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Miyabe
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Miyachi
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Morita
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Muramatsu
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Niiyama
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Nomachi
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Ohashi
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Ooba
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Ohkuma
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Oshuev
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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
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Sugaya
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Sumihama
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Titov
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Toi
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Toyokawa
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Wakai
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Wang
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Wang
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Yonehara
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Yorita
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Yoshimura
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Yosoi
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Zegers
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