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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Low-energy eta-nucleon interaction studied with eta photoproduction off the deuteron

Texto completo
Autor(es):
Nakamura, S. X. [1, 2] ; Kamano, H. [3, 4] ; Ishikawa, T. [5]
Número total de Autores: 3
Afiliação do(s) autor(es):
[1] Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043 - Japan
[2] Univ Cruzeiro Sul, LFTC, BR-01506000 Sao Paulo, SP - Brazil
[3] High Energy Accelerator Res Org KEK, KEK Theory Ctr, IPNS, Tsukuba, Ibaraki 3050801 - Japan
[4] KEK, IPNS, KEK Theory Ctr, J PARC Branch, Tokai, Ibaraki 3191106 - Japan
[5] Tohoku Univ, Res Ctr Electron Photon Sci ELPH, Sendai, Miyagi 9820826 - Japan
Número total de Afiliações: 5
Tipo de documento: Artigo Científico
Fonte: Physical Review C; v. 96, n. 4 OCT 26 2017.
Citações Web of Science: 8
Resumo

We develop a reaction model for eta photoproduction off the deuteron (gamma -> eta pn) and study the reaction at a special kinematics, where the photon beam energy is similar to 0.94 GeV and the scattered proton is detected at similar to 0 degrees, for the purpose of determining the eta-nucleon scattering length (a(eta)N) and effective range (r(eta)N). In this kinematics, the eta-nucleon elastic rescattering is significantly enhanced while other background mechanisms are suppressed. We show that a ratio R, the gamma d -> eta pn cross section divided by the gamma d -> eta p cross section convoluted with the proton momentum distribution in the deuteron, has a very good resolving power of a(eta)N and r(eta)N. We conclude that the R data with 5% error, binned in 1 MeV width of the eta-neutron invariant mass, can determine Re{[}a(eta)N] (Re{[}r(eta)N]) at the precision of similar to +/- 0.1 fm (similar to +/- 0.5 fm), significantly narrowing down the previously estimated ranges of the parameters. To arrive at the conclusion, it is essential to use the gamma d -> eta pn reaction model equipped with elementary amplitudes that are well constrained by pi N and gamma N reaction data through a sophisticated coupled-channel analysis. This result strongly motivates the Research Center for Electron Photon Science (ELPH) at Tohoku University to measure R. (AU)

Processo FAPESP: 16/15618-8 - Análise de Tau e pesados méson hadrônicas decaimentos e neutrino-núcleo interações, para estruturas e interações hadron, e física além do modelo padrão
Beneficiário:Kazuo Tsushima
Linha de fomento: Auxílio à Pesquisa - Pesquisador Visitante - Internacional