학술논문
Measurement of Spin-Density Matrix Elements in $\rho(770)$ Production with a Linearly Polarized Photon Beam at $E_\gamma = 8.2\,-\,8.8\,\text{GeV}$
Document Type
Working Paper
Author
Adhikari, S.; Afzal, F.; Akondi, C. S.; Albrecht, M.; Amaryan, M.; Arroyave, V.; Asaturyan, A.; Austregesilo, A.; Baldwin, Z.; Barbosa, F.; Barlow, J.; Barriga, E.; Barsotti, R.; Beattie, T. D.; Berdnikov, V. V.; Black, T.; Boeglin, W.; Briscoe, W. J.; Britton, T.; Brooks, W. K.; Byer, D.; Chudakov, E.; Cole, P. L.; Cortes, O.; Crede, V.; Dalton, M. M.; Darulis, D.; Deur, A.; Dobbs, S.; Dolgolenko, A.; Dotel, R.; Dugger, M.; Dzhygadlo, R.; Ebersole, D.; Edo, M.; Egiyan, H.; Erbora, T.; Eugenio, P.; Fabrizi, A.; Fanelli, C.; Fang, S.; Fegan, S.; Fitches, J.; Foda, A. M.; Furletov, S.; Gan, L.; Gao, H.; Gardner, A.; Gasparian, A.; Gleason, C.; Goetzen, K.; Goryachev, V. S.; Grube, B.; Guo, J.; Guo, L.; Hague, T. J.; Hakobyan, H.; Hernandez, J.; Hoffman, N. D.; Hornidge, D.; Hou, G.; Huber, G. M.; Hurck, P.; Hurley, A.; Imoehl, W.; Ireland, D. G.; Ito, M. M.; Jaegle, I.; Jarvis, N. S.; Jeske, T.; Jones, R. T.; Kakoyan, V.; Kalicy, G.; Khachatryan, V.; Khatchatryan, M.; Kourkoumelis, C.; LaDuke, A.; Larin, I.; Lawrence, D.; Lersch, D. I.; Li, H.; Liu, B.; Livingston, K.; Lolos, G. J.; Lorenti, L.; Lyubovitskij, V.; Ma, R.; Mack, D.; Mahmood, A.; Marukyan, H.; Matveev, V.; McCaughan, M.; McCracken, M.; Meyer, C. A.; Miskimen, R.; Mitchell, R. E.; Mizutani, K.; Neelamana, V.; Ng, L.; Nissen, E.; Orešić, S.; Ostrovidov, A. I.; Papandreou, Z.; Paudel, C.; Pedroni, R.; Pentchev, L.; Peters, K. J.; Prather, E.; Rakshit, S.; Reinhold, J.; Remington, A.; Ritchie, B. G.; Ritman, J.; Rodriguez, G.; Romanov, D.; Saldana, K.; Salgado, C.; Schadmand, S.; Schertz, A. M.; Scheuer, K.; Schick, A.; Schmidt, A.; Schumacher, R. A.; Schwiening, J.; Sharp, P.; Shen, X.; Shepherd, M. R.; Smith, A.; Smith, E. S.; Sober, D. I.; Somov, A.; Somov, S.; Stevens, J. R.; Strakovsky, I. I.; Sumner, B.; Suresh, K.; Tarasov, V. V.; Taylor, S.; Teymurazyan, A.; Thiel, A.; Viducic, T.; Whitlatch, T.; Wickramaarachchi, N.; Williams, M.; Wunderlich, Y.; Yu, B.; Zarling, J.; Zhang, Z.; Zhao, Z.; Zhou, J.; Zhou, X.; Zihlmann, B.
Source
Phys. Rev. C 108, 055204 (2023)
Subject
Language
Abstract
The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized $8.5\,\text{GeV}$ photons impinging on a hydrogen target which is contained within a detector with near-complete coverage for charged and neutral particles. We present measurements of spin-density matrix elements for the photoproduction of the vector meson $\rho$(770). The statistical precision achieved exceeds that of previous experiments for polarized photoproduction in this energy range by orders of magnitude. We confirm a high degree of $s$-channel helicity conservation at small squared four-momentum transfer $t$ and are able to extract the $t$-dependence of natural and unnatural-parity exchange contributions to the production process in detail. We confirm the dominance of natural-parity exchange over the full $t$ range. We also find that helicity amplitudes in which the helicity of the incident photon and the photoproduced $\rho(770)$ differ by two units are negligible for $-t<0.5\,\text{GeV}^{2}/c^{2}$.
Comment: 15 pages, 11 figures
Comment: 15 pages, 11 figures