Pentaquark $\Theta^+$ search at HERMES
High Energy Physics - Experiment
2015-04-28 v2
Abstract
The earlier search at HERMES for narrow baryon states excited in quasi-real photoproduction, decaying through the channel , has been extended with improved decay-particle reconstruction, more advanced particle identification, and increased event samples. The structure observed earlier at an invariant mass of 1528 MeV shifts to 1522 MeV and the statistical significance drops to about 2 for data taken with a deuterium target. The number of events above background is . No such structure is observed in the hydrogen data set.
Keywords
Cite
@article{arxiv.1412.7317,
title = {Pentaquark $\Theta^+$ search at HERMES},
author = {The HERMES Collaboration and N. Akopov and Z. Akopov and W. Augustyniak and R. Avakian and A. Avetissian and E. Avetisyan and S. Belostotski and H. P. Blok and A. Borissov and J. Bowles and V. Bryzgalov and J. Burns and G. P. Capitani and E. Cisbani and G. Ciullo and M. Contalbrigo and P. F. Dalpiaz and W. Deconinck and R. De Leo and E. De Sanctis and P. Di Nezza and G. Elbakian and E. Etzelmüller and R. Fabbri and A. Fantoni and L. Felawka and S. Frullani and D. Gabbert and J. Garay García and F. Garibaldi and G. Gavrilov and F. Giordano and S. Gliske and M. Hartig and D. Hasch and Y. Holler and I. Hristova and Y. Imazu and A. Ivanilov and H. E. Jackson and S. Joosten and R. Kaiser and G. Karyan and T. Keri and E. Kinney and A. Kisselev and V. Kozlov and P. Kravchenko and V. G. Krivokhijine and L. Lagamba and L. Lapikás and I. Lehmann and A. López Ruiz and W. Lorenzon and X. Lu and B. -Q. Ma and D. Mahon and S. I. Manaenkov and Y. Mao and B. Marianski and A. Martinez de la Ossa and H. Marukyan and C. A. Miller and Y. Miyachi and A. Movsisyan and M. Murray and E. Nappi and A. Nass and M. Negodaev and W. -D. Nowak and L. L. Pappalardo and R. Perez-Benito and A. Petrosyan and P. E. Reimer and A. R. Reolon and C. Riedl and K. Rith and G. Rosner and A. Rostomyan and J. Rubin and D. Ryckbosch and Y. Salomatin and G. Schnell and K. P. Schüler and B. Seitz and T. -A. Shibata and M. Stancari and J. J. M. Steijger and S. Taroian and A. Terkulov and R. Truty and A. Trzcinski and M. Tytgat and Y. Van Haarlem and C. Van Hulse and D. Veretennikov and V. Vikhrov and I. Vilardi and S. Wang and S. Yaschenko and H. Ye and Z. Ye and S. Yen and B. Zihlmann and P. Zupranski},
journal= {arXiv preprint arXiv:1412.7317},
year = {2015}
}