Azimuthal asymmetries of back-to-back π±- (π0, η, π±) pairs in e+e- annihilation
This work reports the first observation of azimuthal asymmetries around the thrust axis in e+e- annihilation of pairs of back-to-back charged pions in one hemisphere, and π0 and η mesons in the opposite hemisphere. These results are complemented by a new analysis of pairs of back-to-back charged pions. The π0 and η asymmetries rise with the relative momentum z of the detected hadrons as well as with the transverse momentum with respect to the thrust axis. These asymmetries are sensitive to the Collins fragmentation function H1¥ and provide complementary information to previous measurements with charged pions and kaons in the final state. In particular, the η final states will provide additional information on the flavor structure of H1¥. This is the first measurement of the explicit transverse-momentum dependence of the Collins fragmentation function from Belle data. It uses a dataset of 980.4 fb-1 collected by the Belle experiment at or near a center-of-mass energy of 10.58 GeV.
Li, H; Vossen, A; Aihara, H; Asner, DM; Aulchenko, V; Aushev, T; Babu, V; Badhrees, I; Bakich, AM; Bennett, J; Bhardwaj, V; Bilka, T; Biswal, J; Bobrov, A; Bračko, M; Campajola, M; Cao, L; Červenkov, D; Chekelian, V; Chen, A; Cheon, BG; Cho, HE; Cho, K; Choi, Y; Choudhury, S; Cinabro, D; Cunliffe, S; Di Capua, F; Di Carlo, S; Dong, TV; Eidelman, S; Ferber, T; Fulsom, BG; Gaur, V; Garmash, A; Giri, A; Goldenzweig, P; Hartbrich, O; Hayasaka, K; Hayashii, H; Huang, K; Inami, K; Ishikawa, A; Itoh, R; Iwasaki, M; Jacobs, WW; Jang, EJ; Jia, S; Jin, Y; Kang, KH; Karyan, G; Kim, DY; Kim, SH; Kodyš, P; Korpar, S; Kotchetkov, D; KriŽan, P; Kroeger, R; Krokovny, P; Kwon, YJ; Lee, SC; Li, YB; Li Gioi, L; Libby, J; Lieret, K; Liventsev, D; Luo, T; Macqueen, C; Masuda, M; Matsuda, T; Merola, M; Miyabayashi, K; Miyata, H; Mizuk, R; Mussa, R; Nakano, T; Nakao, M; Naruki, M; Nath, KJ; Natkaniec, Z; Nishida, S; Ono, H; Ostrowicz, W; Pakhlov, P; Pakhlova, G; Pal, B; Pardi, S; Patra, S; Paul, S; Pedlar, TK; Pestotnik, R; Piilonen, LE; Popov, V; Prencipe, E; Prim, MT; Russo, G; Sahoo, D; Sakai, Y; Santelj, L; Sanuki, T
Volume / Issue
Electronic International Standard Serial Number (EISSN)
International Standard Serial Number (ISSN)
Digital Object Identifier (DOI)