Azimuthal asymmetries of back-to-back π±- (π0, η, π±) pairs in e+e- annihilation

Date Issued
27-11-2019
Author(s)
Li, H.
Vossen, A.
Aihara, H.
Asner, D. M.
Aulchenko, V.
Aushev, T.
Babu, V.
Badhrees, I.
Bakich, A. M.
Bennett, J.
Bhardwaj, V.
Bilka, T.
Biswal, J.
Bobrov, A.
BraÄ ko, M.
Campajola, M.
Cao, L.
ÄŒervenkov, D.
Chekelian, V.
Chen, A.
Cheon, B. G.
Cho, H. E.
Cho, K.
Choi, Y.
Choudhury, S.
Cinabro, D.
Cunliffe, S.
Di Capua, F.
Di Carlo, S.
Dong, T. V.
Eidelman, S.
Ferber, T.
Fulsom, B. G.
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, W. W.
Jang, E. J.
Jia, S.
Jin, Y.
Kang, K. H.
Karyan, G.
Kim, D. Y.
Kim, S. H.
Kodyš, P.
Korpar, S.
Kotchetkov, D.
KriŽan, P.
Kroeger, R.
Krokovny, P.
Kwon, Y. J.
Lee, S. C.
Li, Y. B.
Li Gioi, L.
Indian Institute of Technology, Madras
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, K. J.
Natkaniec, Z.
Nishida, S.
Ono, H.
Ostrowicz, W.
Pakhlov, P.
Pakhlova, G.
Pal, B.
Pardi, S.
Patra, S.
Paul, S.
Pedlar, T. K.
Pestotnik, R.
Piilonen, L. E.
Popov, V.
Prencipe, E.
Prim, M. T.
Russo, G.
Sahoo, D.
Sakai, Y.
Santelj, L.
Sanuki, T.
DOI
Abstract
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.
Volume
100