Journal article

Transverse polarization of Λ and (Λ)over-bar hyperons in quasireal photoproduction


Authors listAirapetian, A.; Akopov, N.; Akopov, Z.; Amarian, M.; Ammosov, V. V.; Andrus, A.; Aschenauer, E. C.; Augustyniak, W.; Avakian, R.; Avetissian, A.; Avetissian, E.; Bailey, P.; Baturin, V.; Baumgarten, C.; Beckmann, M.; Belostotski, S.; Bernreuther, S.; Bianchi, N.; Blok, H. P.; Boettcher, H.; Borissov, A.; Bouwhuis, M.; Brack, J.; Bruell, A.; Brunn, I.; Capitani, G. P.; Chiang, H. C.; Ciullo, G.; Contalbrigo, M.; Court, G. R.; Dalpiaz, P. F.; De Leo, R.; De Nardo, L.; De Sanctis, E.; Devitsin, E.; Di Nezza, P.; Dueren, M.; Ehrenfried, M.; Elalaoui-Moulay, A.; Elbakian, G.; Ellinghaus, F.; Elschenbroich, U.; Ely, J.; Fabbri, R.; Fantoni, A.; Fechtchenko, A.; Felawka, L.; Fox, B.; Franz, J.; Frullani, S.; Gaerber, Y.; Gapienko, G.; Gapienko, V.; Garibaldi, F.; Garutti, E.; Gaskell, D.; Gavrilov, G.; Gharibyan, V.; Graw, G.; Grebeniouk, O.; Greeniaus, L. G.; Haeberli, W.; Hafidi, K.; Hartig, M.; Hasch, D.; Heesbeen, D.; Henoch, M.; Hertenberger, R.; Hesselink, W. H. A.; Hillenbrand, A.; Holler, Y.; Hommez, B.; Iarygin, G.; Izotov, A.; Jackson, H. E.; Jgoun, A.; Kaiser, R.; Kinney, E.; Kisselev, A.; Koenigsmann, K.; Kolster, H.; Kopytin, M.; Korotkov, V.; Kozlov, V.; Krauss, B.; Krivokhijine, V. G.; Lagamba, L.; Lapikas, L.; Laziev, A.; Lenisa, P.; Liebing, P.; Lindemann, T.; Lipka, K.; Lorenzon, W.; Makins, N. C. R.; Marukyan, H.; Masoli, F.; Menden, F.; Mexner, V.; Meyners, N.; Mikloukho, O.; Miller, C. A.; Miyachi, Y.; Muccifora, V.; Nagaitsev, A.; Nappi, E.; Naryshkin, Y.; Nass, A.; Nowak, W. -D.; Oganessyan, K.; Ohsuga, H.; Orlandi, G.; Potashov, S.; Potterveld, D. H.; Raithel, M.; Reggiani, D.; Reimer, P. E.; Reischl, A.; Reolon, A. R.; Rith, K.; Rosner, G.; Rostomyan, A.; Ryckbosch, D.; Sanjiev, I.; Savin, I.; Scarlett, C.; Schaefer, A.; Schill, C.; Schnell, G.; Schueler, K. P.; Schwind, A.; Seibert, J.; Seitz, B.; Shanidze, R.; Shibata, T. -A.; Shutov, V.; Simani, M. C.; Sinram, K.; Stancari, M.; Statera, M.; Steffens, E.; Steijger, J. J. M.; Stewart, J.; Stoesslein, U.; Tanaka, H.; Taroian, S.; Tchuiko, B.; Terkulov, A.; Tessarin, S.; Thomas, E.; Tkabladze, A.; Trzcinski, A.; Tytgat, M.; Urciuoli, G. M.; van der Nat, P. B.; van der Steenhoven, G.; van de Vyver, R.; Veretennikov, D.; Vetterli, M. C.; Vikhrov, V.; Vincter, M. G.; Visser, J.; Vogt, M.; Volmer, J.; Weiskopf, C.; Wendland, J.; Wilbert, J.; Wise, T.; Yen, S.; Yoneyama, S.; Zihlmann, B.; Zohrabian, H.; Zupranski, P.

Publication year2007

JournalPhysical Review D

Volume number76

Issue number9

ISSN1550-7998

eISSN1550-2368

DOI Linkhttps://doi.org/10.1103/PhysRevD.76.092008

PublisherAmerican Physical Society


Abstract
The HERMES experiment has measured the transverse polarization of Lambda and (Lambda) over bar hyperons produced inclusively in quasireal photoproduction at a positron beam energy of 27.6 GeV. The transverse polarization P-n(Lambda) of the Lambda hyperon is found to be positive while the observed (Lambda) over bar polarization is compatible with zero. The values averaged over the kinematic acceptance of HERMES are P-n(Lambda)=0.078 +/- 0.006(stat)+/- 0.012(syst) and P-n((Lambda) over bar)=-0.025 +/- 0.015(stat)+/- 0.018(syst) for Lambda and (Lambda) over bar, respectively. The dependences of P-n(Lambda) and P-n((Lambda) over bar) on the fraction zeta of the beam's light-cone momentum carried by the hyperon and on the hyperon's transverse momentum p(T) were investigated. The measured Lambda polarization rises linearly with p(T) and exhibits a different behavior for low and high values of zeta, which approximately correspond to the backward and forward regions in the center-of-mass frame of the gamma*N reaction.



Citation Styles

Harvard Citation styleAirapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V., Andrus, A., et al. (2007) Transverse polarization of Λ and (Λ)over-bar hyperons in quasireal photoproduction, PHYSICAL REVIEW D, 76(9), Article 092008. https://doi.org/10.1103/PhysRevD.76.092008

APA Citation styleAirapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V., Andrus, A., Aschenauer, E., Augustyniak, W., Avakian, R., Avetissian, A., Avetissian, E., Bailey, P., Baturin, V., Baumgarten, C., Beckmann, M., Belostotski, S., Bernreuther, S., Bianchi, N., Blok, H., ...Zupranski, P. (2007). Transverse polarization of Λ and (Λ)over-bar hyperons in quasireal photoproduction. PHYSICAL REVIEW D. 76(9), Article 092008. https://doi.org/10.1103/PhysRevD.76.092008



Keywords


800-GEV/C PROTONSGEV/CINCLUSIVE HADRON-PRODUCTIONNUCLEONPHOTON ENERGIESP INTERACTIONS

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