Measurement of Spin-Density Matrix Elements in $\rho(770)$ Production
with a Linearly Polarized Photon Beam at $E_\gamma = 8.2\,-\,8.8\,\text{GeV}$
S. Adhikari,F. Afzal,C. S. Akondi,M. Albrecht,M. Amaryan,V. Arroyave,A. Asaturyan,A. Austregesilo,Z. Baldwin,F. Barbosa,J. Barlow,E. Barriga,R. Barsotti,T. D. Beattie,V. V. Berdnikov,T. Black,W. Boeglin,W. J. Briscoe,T. Britton,W. K. Brooks,D. Byer,E. Chudakov,P. L. Cole,O. Cortes,V. Crede,M. M. Dalton,D. Darulis,A. Deur,S. Dobbs,A. Dolgolenko,R. Dotel,M. Dugger,R. Dzhygadlo,D. Ebersole,M. Edo,H. Egiyan,T. Erbora,P. Eugenio,A. Fabrizi,C. Fanelli,S. Fang,S. Fegan,J. Fitches,A. M. Foda,S. Furletov,L. Gan,H. Gao,A. Gardner,A. Gasparian,C. Gleason,K. Goetzen,V. S. Goryachev,B. Grube,J. Guo,L. Guo,T. J. Hague,H. Hakobyan,J. Hernandez,N. D. Hoffman,D. Hornidge,G. Hou,G. M. Huber,P. Hurck,A. Hurley,W. Imoehl,D. G. Ireland,M. M. Ito,I. Jaegle,N. S. Jarvis,T. Jeske,R. T. Jones,V. Kakoyan,G. Kalicy,V. Khachatryan,M. Khatchatryan,C. Kourkoumelis,A. LaDuke,I. Larin,D. Lawrence,D. I. Lersch,H. Li,B. Liu,K. Livingston,G. J. Lolos,L. Lorenti,V. Lyubovitskij,R. Ma,D. Mack,A. Mahmood,H. Marukyan,V. Matveev,M. McCaughan,M. McCracken,C. A. Meyer,R. Miskimen,R. E. Mitchell,K. Mizutani,V. Neelamana,L. Ng,E. Nissen,S. Orešić,A. I. Ostrovidov,Z. Papandreou,C. Paudel,R. Pedroni,L. Pentchev,K. J. Peters,E. Prather,S. Rakshit,J. Reinhold,A. Remington,B. G. Ritchie,J. Ritman,G. Rodriguez,D. Romanov,K. Saldana,C. Salgado,S. Schadmand,A. M. Schertz,K. Scheuer,A. Schick,A. Schmidt,R. A. Schumacher,J. Schwiening,P. Sharp,X. Shen,M. R. Shepherd,A. Smith,E. S. Smith,D. I. Sober,S. Somov,A. Somov,J. R. Stevens,I. I. Strakovsky,B. Sumner,K. Suresh,V. V. Tarasov,S. Taylor,A. Teymurazyan,A. Thiel,T. Viducic,T. Whitlatch,N. Wickramaarachchi,M. Williams,Y. Wunderlich,B. Yu,J. Zarling,Z. Zhang,Z. Zhao,X. Zhou,J. Zhou,B. Zihlmann
arXiv (Cornell University)（2023）
引用0|浏览3
暂无评分
摘要
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 $-t<0.5\,\text{GeV}^{2}/c^{2}$.
