Measurement of spin-density matrix elements in ρ ( 770 ) production with a linearly polarized photon beam at E γ = 8.2 – 8.8   GeV

Journal Article · 14 November 2023 · Physical Review. C

DOI: https://doi.org/10.1103/physrevc.108.055204 · OSTI ID:2217104

Adhikari, S. ^[1]; 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.

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1. Old Dominion University, Norfolk, VA (United States). GlueX Collaboration. et al

The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized 8.5GeV 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. Here 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<0.5GeV²/c².

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• Contributing Organization: GlueX Collaboration
• Grant/Contract Number: FG02-87ER40315; AC05-06OR23177
• OSTI ID: 2217104
• Alternate ID(s): OSTI ID: 2208863
• Report Number(s): JLAB-PHY--23-3838; arXiv:2305.09047; DOE/OR/23177--6282
• Journal Information: Physical Review. C, Journal Name: Physical Review. C Journal Issue: 5 Vol. 108; ISSN 2469-9985
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English