1301.6183 (Belle Collaboration et al.)

Precision measurement of charged pion and kaon multiplicities in
electron-positron annihilation at Q = 10.52 GeV    [PDF]

Belle Collaboration, M. Leitgab, R. Seidl, M. Grosse Perdekamp, A. Vossen, I. Adachi, H. Aihara, D. M. Asner, V. Aulchenko, T. Aushev, A. M. Bakich, B. Bhuyan, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, T. E. Browder, V. Chekelian, A. Chen, P. Chen, B. G. Cheon, K. Chilikin, K. Cho, V. Chobanova, Y. Choi, D. Cinabro, J. Dalseno, Z. Drásal, D. Dutta, S. Eidelman, D. Epifanov, H. Farhat, J. E. Fast, V. Gaur, N. Gabyshev, R. Gillard, F. Giordano, Y. M. Goh, B. Golob, J. Haba, K. Hayasaka, H. Hayashii, Y. Hoshi, W. -S. Hou, Y. B. Hsiung, H. J. Hyun, T. Iijima, A. Ishikawa, R. Itoh, W. W. Jacobs, T. Julius, J. H. Kang, P. Kapusta, E. Kato, T. Kawasaki, H. J. Kim, H. O. Kim, J. B. Kim, J. H. Kim, M. J. Kim, J. Klucar, B. R. Ko, P. Kodyš, R. T. Kouzes, P. Križan, P. Krokovny, R. Kumar, T. Kumita, Y. -J. Kwon, J. S. Lange, S. -H. Lee, Y. Li, Z. Q. Liu, D. Liventsev, D. Matvienko, K. Miyabayashi, H. Miyata, R. Mizuk, A. Moll, N. Muramatsu, E. Nakano, M. Nakao, Z. Natkaniec, M. Nayak, E. Nedelkovska, C. Ng, N. Nellikunnummel, O. Nitoh, A. Ogawa, S. Ogawa, T. Ohshima, S. Okuno, S. L. Olsen, C. Oswald, P. Pakhlov, H. Park, H. K. Park, T. K. Pedlar, R. Pestotnik, M. Petrič, L. E. Piilonen, M. Röhrken, H. Sahoo, Y. Sakai, S. Sandilya, L. Santelj, T. Sanuki, Y. Sato, O. Schneider, G. Schnell, C. Schwanda, K. Senyo, O. Seon, M. E. Sevior, M. Shapkin, C. P. Shen, T. -A. Shibata, J. -G. Shiu, B. Shwartz, A. Sibidanov, F. Simon, P. Smerkol, Y. -S. Sohn, A. Sokolov, E. Solovieva, M. Starič, M. Sumihama, T. Sumiyoshi, G. Tatishvili, Y. Teramoto, T. Tsuboyama, M. Uchida, T. Uglov, Y. Unno, S. Uno, Y. Usov, C. Van Hulse, G. Varner, V. Vorobyev, M. N. Wagner, C. H. Wang, J. Wang, M. -Z. Wang, P. Wang, M. Watanabe, Y. Watanabe, K. M. Williams, E. Won, Y. Yamashita, V. Zhilich, V. Zhulanov

Precise measurements of inclusive multiplicities of charged pions and kaons produced in electron-positron annihilation have been carried out at a center-of-mass energy of 10.52 GeV. The measurements were performed with the Belle detector at the KEKB electron-positron collider using a data sample containing 113 million e+e- -> qqbar events, where q={u,d,s,c}. We present charge-integrated multiplicities 1/N_evts * dN_h+-/dz for h+- = pi+-, K+- as a function of the relative hadron energy z = 2*E_h / sqrt{s} from 0.2 to 0.98 (0.97) for pions (kaons). The combined statistical and systematic uncertainties for pi+- (K+-) are 4% (5%) at z ~ 0.6 and 18% (51%) at z ~ 0.9. The multiplicities are the first measurements of the z-dependence of pion and kaon multiplicities for z > 0.7 as well as the first precision multiplicity measurements at a center-of-mass energy far below the Z^0 resonance used by the experiments at LEP and SLC.

View original: http://arxiv.org/abs/1301.6183