Measurements of Beam Spin Asymmetries of $π^\pmπ^0$ dihadrons at CLAS12
University of York（约克大学）；Christopher Newport University（克里斯托弗纽波特大学）；Universit’e Paris-Saclay, CNRS/IN2P3, IJCLab（巴黎萨克雷大学）；Old Dominion University（老道明大学）；Argonne National Laboratory（阿贡国家实验室）；Temple University（天普大学）；Thomas Jefferson National Accelerator Facility（托马斯杰斐逊国家加速设施）；INFN, Sezione di Ferrara（意大利国家核物理研究所费拉拉分部）；INFN, Sezione di Genova（意大利国家核物理研究所热那亚分部）；Duquesne University（杜肯大学）；Universit‘a degli Studi di Brescia（布雷西亚大学）；INFN, Sezione di Pavia（意大利国家核物理研究所帕维亚分部）；Fairfield University（费尔菲尔德大学）；II Physikalisches Institut der Universitaet Giessen（吉森大学第二物理研究所）；IRFU, CEA, Universit’e Paris-Saclay（法国原子能和替代能源委员会）；The George Washington University（乔治华盛顿大学）
A. G. Acar, P. Achenbach, J. S. Alvarado, M. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, N. A. Baltzell, L. Barion, M. Battaglieri, F. Benmokhtar, A. Biancon… 展开作者
A. G. Acar, P. Achenbach, J. S. Alvarado, M. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, N. A. Baltzell, L. Barion, M. Battaglieri, F. Benmokhtar, A. Bianconi, A. S. Biselli, K. -T. Brinkmann, F. Bossù, W. J. Briscoe, S. Bueltmann, V. D. Burkert, D. S. Carman, T. Cao, A. Celentano, P. Chatagnon, H. Chinchay, G. Ciullo, P. L. Cole, M. Contalbrigo, A. D'Angelo, N. Dashyan, R. De Vita, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, L. El Fassi, M. Farooq, S. Fegan, E. Ferrand, I. P. Fernando, A. Filippi, C. Fogler, K. Gates, G. Gavalian, G. P. Gilfoyle, D. I. Glazier, R. W. Gothe, Y. Gotra, B. Gualtieri, M. Hattawy, T. B. Hayward, M. Hoballah, D. Holmberg, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. S. Jo, S. Joosten, T. Kageya, D. Keller, H. Klest, V. Klimenko, A. Kripko, V. Kubarovsky, S. E. Kuhn, L. Lanza, P. Lenisa, X. Li, D. Marchand, D. Martiryan, V. Mascagna, G. Matousek, B. McKinnon, Z. E. Meziani, R. G. Milner, T. Mineeva, M. Mirazita, V. Mokeev, E. F. Molina Cardenas, C. Munoz Camacho, P. Nadel-Turonski, T. Nagorna, K. Neupane, S. Niccolai, G. Niculescu, M. Osipenko, M. Ouillon, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, C. Paudel, S. J. Paul, W. Phelps, N. Pilleux, P. S. H. Vaishnavi, L. Polizzi, J. Poudel, Y. Prok, A. Radic, J. Richards, M. Ripani, J. Ritman, P. Rossi, A. A. Rusova, S. Schadmand, A. Schmidt, Y. G. Sharabian, E. V. Shirokov, S. Shrestha, E. Sidoretti, D. Sokhan, N. Sparveris, M. Spreafico, I. I. Strakovsky, S. Strauch, F. Touchte Codjo, R. Tyson, M. Ungaro, D. W. Upton, C. Velasquez, L. Venturelli, H. Voskanyan, E. Voutier, A. Vossen, Y. Wang, U. Weerasinghe, X. Wei, N. Wickramaarachchi, L. Xu, Z. Xu, Z. W. Zhao
本文报告了在半包容深度非弹性散射中，对π+π⁰和π-π⁰双核子的束流自旋不对称性首次测量。通过将10.6 GeV纵向极化电子束散射到质子靶上，利用杰弗逊实验室的CLAS12探测器测量了双核子角分布中的不对称性。通过使用基于梯度提升树（GBTs）架构的光子分类器，利用蒙特卡洛模拟减少虚假组合背景π⁰的数量，使统计量提高了五倍以上。观测到非零的sinϕ_{R_⊥}不对称性。该测量对未被充分探索的线性扭-3 PDF e(x)敏感，该PDF编码了质子中的夸克-胶子相关性，并提供了一种新的逐点提取方法。这些不对称性还为双核子碎片函数G_1^⊥的宇称依赖性提供了首次实验证据，通过π+π⁰和π-π⁰通道在sin(ϕ_h-ϕ_{R_⊥})调制中的符号差异揭示出来。相比之下，在sin(2ϕ_h-2ϕ_{R_⊥})调制中观察到较大的同号增强，在ρ质量附近，与π+π-对的旁观者模型预测相匹配。
英文摘要：
A first measurement of beam spin asymmetries for $π^+π^0$ and $π^-π^0$ pairs in semi-inclusive deep inelastic scattering is reported. The asymmetries in the dihadron angular distributions were measured from the scattering of a 10.6 GeV longitudinally polarized electron beam off a proton target, using the CLAS12 detector at Jefferson Lab. A photon classifier using a Gradient Boosted Trees (GBTs) architecture was trained with Monte Carlo simulations to reduce the amount of false combinatorial background $π^0$s, increasing statistics by up to five-fold compared to previous CLAS12 $π^0$ analyses. A nonzero $\sinϕ_{R_\perp}$ asymmetry is observed. This measurement is sensitive to the underexplored collinear twist-3 PDF $e(x)$, which encodes quark-gluon correlations in the proton, and presents a new avenue for its point-by-point extraction. The asymmetries also provide the first experimental evidence for the isospin-dependence of the helicity-dependent dihadron fragmentation function $G_1^\perp$, revealed by a sign-difference between the $π^+π^0$ and $π^-π^0$ channels in the $\sin(ϕ_h-ϕ_{R_\perp})$ modulation. In contrast, a large, same-sign enhancement near the $ρ$ mass for the $\sin(2ϕ_h-2ϕ_{R_\perp})$ modulation is observed, matching spectator model predictions in $π^+π^-$ pairs.
Azimuthal Correlations in the Structure Functions of polarized Dihadron Semi-Inclusive Deep Inelastic Scattering
讨论了非极化轻子与横极化核子深度非弹性散射中两个强子产生的方位角关联。具体地说，一个简单的方法来访问对应于Sivers效应和横向诱导的单自旋方位角不对称性的结构函数的非极化结构函数的比率。然后将这种方法应用于由包括Sivers效应的LEPTO Monte Carlo事件发生器的修改版本生成的样本伪数据。利用这些数据，它示出，方位角的相关性在Sivers的结构功能和非极化结构功能是显着不同的。在一个双强子样品中的柯林斯一样的单强子不对称性也进行了讨论，其中的实验结果最近提出的COMPASS合作。
Dihadron azimuthal asymmetry and light-quark dipole moments at the Electron-Ion Collider
School of Physics, Peking University（北京大学物理学院）；Institute of High Energy Physics, Chinese Academy of Sciences（中国科学院高能物理研究所）；China Center of Advanced Science and Technology（中国科学技术大学北京校区）；Center for High Energy Physics, Peking University（北京大学高能物理中心）；Theory Center, Jefferson Lab（杰斐逊实验室理论中心）；High EnergyTheory Group, Physics Department,Brookhaven National Laboratory（布鲁克海文国家实验室物理系高能理论组）；Department of Physics and Astronomy, Michigan State University（密歇根州立大学物理与天文学系）
Transverse spin effects and light-quark dipole moments at colliders
Institute of High Energy Physics, Chinese Academy of Sciences（中国科学院高能物理研究所）；China Center of Advanced Science and Technology（中国高等科学技术中心）；Peking University（北京大学）；Brookhaven National Laboratory（布鲁克海文国家实验室）；Michigan State University（密歇根州立大学）
Measurement of Azimuthal Asymmetries With Respect To Both Beam Charge and Transverse Target Polarization in Exclusive Electroproduction of Real Photons
Probing Quark Electromagnetic Properties via Entangled Quark Pairs in Fragmentation Hadrons at Lepton Colliders
Peking University（北京大学）；Zhengzhou University（郑州大学）；Institute of High Energy Physics, Chinese Academy of Sciences（中国科学院高能物理研究所）；University of Chinese Academy of Sciences（中国科学院大学）；China Center of Advanced Science and Technology（中国高等科学技术中心）
CP-violating ZZh Coupling at e+e- Linear Colliders
我们研究了具有CP破坏的广义Higgs-弱玻色子耦合通过过程e+e- -> f \bar f h.我们通过子过程Zh产生和ZZ融合对信号通道进行分类，并通过利用偏振e+e-束来构建四个CP不对称。我们发现子过程之间的互补性和不对称性，以探测违反CP的形状因子的实部和虚部。非偏振光束的某些不对称性可以保持对耦合的显著敏感性。我们的结论是，在线性对撞机与高亮度，CP奇ZZh耦合可以灵敏地探测通过测量的不对称性。
