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Study Of The Reactions E+E-→Π+Π-Π0Π0Π0 And Π+Π-Π0Π0Η At Center-Of-Mass Energies From Threshold To 4.35 Gev Using Initial-State Radiation, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, V. B. Golubev, E. A. Kozyrev, Milind Purohit, Et. Al.

Faculty Publications

We study the processes e⁺e⁻ → π⁺π⁻π⁰π⁰π⁰nγ in which an energetic photon is radiated from the initial state. The data are collected with the BABAR detector at SLAC. About 14 000 and 4700 events, respectively, are selected from a data sample corresponding to an integrated luminosity of 469 fb⁻¹. The invariant mass of the hadronic final state defines the effective e⁺e⁻ center-of-mass energy. From the mass spectra, the first precise measurement of the e⁺e⁻ → π⁺π^{− …}

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Production Cross Sections Of Hyperons And Charmed Baryons From E + E − Annihilation Near √ S = 10.52 Gev, M. Niiyama Et Al., D. Joffe, Ratnappuli L. Kulasiri

Faculty and Research Publications

We measure the inclusive production cross sections of hyperons and charmed baryons from e+e−annihilation using a 800 fb−1 data sample taken near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider. The feed-down contributions from heavy particles are subtracted using our data, and the direct production cross sections are presented for the first time. The production cross sections divided by the number of spin states for S=−1 hyperons follow an exponential function with a single slope parameter except for the Σ(1385)+ resonance. Suppression for Σ(1385)+ and Ξ(1530)0 hyperons is observed. Among the production cross sections of …

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Observation Of Excited Ω C Charmed Baryons In E + E − Collisions, J. Yelton, Ratnappuli L. Kulasiri

Faculty and Research Publications

Using the entire Belle data sample of 980 fb−1 of e+e− collisions, we present the results of a study of excited Ωc charmed baryons in the decay mode Ξ+cK−. We show confirmation of four of the five narrow states reported by the LHCb Collaboration: the Ωc(3000), Ωc(3050), Ωc(3066), and Ωc(3090).

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Study Of K 0 S Pair Production In Single-Tag Two-Photon Collisions, M. Masuda Et Al., Ratnappuli L. Kulasiri

Faculty and Research Publications

We report a measurement of the cross section for K0S pair production in single-tag two-photon collisions, γ∗γ→K0SK0S, for Q2 up to 30 GeV2, where Q2 is the negative of the invariant mass squared of the tagged photon. The measurement covers the kinematic range 1.0 GeV

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Azimuthal Transverse Single-Spin Asymmetries Of Inclusive Jets And Charged Pions Within Jets From Polarized-Proton Collisions At √S = 500 Gev, L. Adamczyk, J. R. Adams, James K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, N. N. Ajitanand, I. Alekseev, D. M. Anderson, R. Aoyama, A. Aparin, D. Arkhipkin, E. C. Aschenauer, M. U. Ashraf, A. Attri, G. S. Averichev, X. Bai, V. Bairathi, K. Barish, A. Behera, R. Bellwied, A. Bhasin, A. K. Bhati, P. Bhattarai, J. Bielcik, J. Bielcikova, L. C. Bland, I. G. Bordyuzhin, J. Bouchet, J. D. Brandenburg, Renee H. Fatemi, Suvarna Ramachandran

Physics and Astronomy Faculty Publications

We report the first measurements of transverse single-spin asymmetries for inclusive jet and jet + π^± production at midrapidity from transversely polarized proton-proton collisions at √s = 500 GeV. The data were collected in 2011 with the STAR detector sampled from 23 pb⁻¹ integrated luminosity with an average beam polarization of 53%. Asymmetries are reported for jets with transverse momenta 6 < p_T < 55 GeV/c and pseudorapidity |η| < 1. Presented are measurements of the inclusive-jet azimuthal transverse single-spin asymmetry, sensitive to twist-3 initial-state quark-gluon correlators; the Collins asymmetry, sensitive to quark transversity coupled to the polarized Collins fragmentation function; and the first measurement of the “Collins-like” asymmetry, sensitive to linearly polarized gluons. Within the present statistical precision, inclusive-jet and Collins-like asymmetries are small, with the latter allowing the first experimental constraints on gluon linear polarization in a polarized proton. At higher values of jet transverse momenta, we observe the first nonzero Collins asymmetries in polarized-proton collisions, with a statistical significance of greater than 5σ. The results span a range of x similar to results from semi-inclusive deep-inelastic scattering but at much higher Q². The Collins results enable tests of …

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Faculty Publications

Production Cross Sections Of Hyperons And Charmed Baryons From E + E − Annihilation Near √ S = 10.52 Gev, M. Niiyama Et Al., D. Joffe, Ratnappuli L. Kulasiri

Faculty and Research Publications

Observation Of Excited Ω C Charmed Baryons In E + E − Collisions, J. Yelton, Ratnappuli L. Kulasiri

Faculty and Research Publications

Study Of K 0 S Pair Production In Single-Tag Two-Photon Collisions, M. Masuda Et Al., Ratnappuli L. Kulasiri

Faculty and Research Publications

Physics and Astronomy Faculty Publications