Upper Limit on the Photoproduction Cross Section of the Spin-Exotic $π_1(1600)$
GlueX Collaboration, F. Afzal, C. S. Akondi, M. Albrecht, M. Amaryan, S. Arrigo, V. Arroyave, A. Asaturyan, A. Austregesilo, Z. Baldwin, F. Barbosa, J. Barlow, … 展开作者
GlueX Collaboration, F. Afzal, C. S. Akondi, M. Albrecht, M. Amaryan, S. Arrigo, V. Arroyave, A. Asaturyan, A. Austregesilo, Z. Baldwin, F. Barbosa, J. Barlow, E. Barriga, R. Barsotti, D. Barton, V. Baturin, V. V. Berdnikov, T. Black, W. Boeglin, M. Boer, W. J. Briscoe, T. Britton, S. Cao, E. Chudakov, G. Chung, P. L. Cole, O. Cortes, V. Crede, M. M. Dalton, D. Darulis, A. Deur, S. Dobbs, A. Dolgolenko, M. Dugger, R. Dzhygadlo, D. Ebersole, M. Edo, H. Egiyan, T. Erbora, P. Eugenio, A. Fabrizi, C. Fanelli, S. Fang, J. Fitches, A. M. Foda, S. Furletov, L. Gan, H. Gao, A. Gardner, A. Gasparian, D. Glazier, C. Gleason, V. S. Goryachev, B. Grube, J. Guo, L. Guo, J. Hernandez, K. Hernandez, N. D. Hoffman, D. Hornidge, G. Hou, P. Hurck, A. Hurley, W. Imoehl, D. G. Ireland, M. M. Ito, I. Jaegle, N. S. Jarvis, T. Jeske, M. Jing, R. T. Jones, V. Kakoyan, G. Kalicy, V. Khachatryan, 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, N. Septian, P. Sharp, X. Shen, M. R. Shepherd, J. Sikes, A. Smith, E. S. Smith, D. I. Sober, A. Somov, S. 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, Y. Wunderlich, B. Yu, J. Zarling, Z. Zhang, X. Zhou, B. Zihlmann
The spin-exotic hybrid meson $π_{1}(1600)$ is predicted to have a large decay rate to the $ωππ$ final state. Using 76.6~pb$^{-1}$ of data collected with the GlueX detector, we measure the cross sections for the reactions $γp \to ωπ^+ π^- p$, $γp \to ωπ^0 π^0 p$, and $γp\toωπ^-π^0Δ^{++}$ in the range $E_γ=$ 8-10 GeV. Using isospin conservation, we set the first upper limits on the photoproduction cross sections of the $π^{0}_{1}(1600)$ and $π^{-}_{1}(1600)$. We combine these limits with lattice calculations of decay widths and find that photoproduction of $η'π$ is the most sensitive two-body system to search for the $π_1(1600)$.
Incoherent $ρ$ meson photoproduction in ultraperipheral nuclear collisions at the LHC
利用Gribov-Glauber模型的光子-核散射和广义矢量介子模型的光子强子结构，对大型强子对撞机中Pb-Pb超周边碰撞（UPC）中的非相干光生$ρ$截面进行了预测.我们发现，非弹性核阴影的影响是显着的，并导致额外的25%的抑制的非相干截面。将我们的预测与STARlight Monte Carlo框架的预测进行比较，我们观察到非常显著的差异。
On the Extraction of Cross Sections for pi0 and eta Photoproduction off Neutrons from Deuteron Data
本文讨论了从氘核数据中提取中性赝标介子离中子光生截面的过程。主要的陈述是，质子和中子靶的末态相互作用（FSI）修正通常是不相等的，但对于π 0的产生，有一些特殊情况，它们必须是相同的，并且在入射光子能量和π极角θ^* 的参数空间中有很大的区域，它们碰巧非常相似。由于这种激发的特定的同位旋结构，在Delta（1232）3/2+共振的能量范围内，对于$π_0$的产生，对两个靶核子的校正实际上是相同的。同样在$Δ$ -等压线范围以上，质子和中子修正因子之间的大差异仅在极端前向角（$θ^*$ < 20度）下预测，但结果在较大角下相似。讨论了gp-> pi 0 p和gn-> pi 0 n修正因子的数值结果。并给出了gd--> pi 0 pn截面的模型描述。
Nuclear effects in photoproduction of heavy quarks and vector mesons in ultraperipheral PbPb and pPb collisions at the LHC
通过比较$c\bar{c}$和b-b（bar）在PbPb和pPb碰撞中的光生截面，可以得到对核遮蔽效应的敏感性.光生矢量介子对底层胶子的分布更为敏感。本文研究了在sqrt（s_NN）=5 TeV和sqrt（s_NN）=2.76 $ TeV, respectively. The potentials of using these processes for constraining nuclear gluon shadowing are explored. It is found that photoproduction of $ J/J条件下，在大型强子对撞机上进行的超周边pPb和PbPb碰撞中，重夸克光生和矢量介子光生的截面及其与快度的关系。特别是PbPb碰撞中的$ and $对胶子遮蔽表现出很好的敏感性。
Investigating the impact of the gluon saturation effects on the momentum transfer distributions for the exclusive vector meson photoproduction in hadronic collisions
