Ramírez M A, Akhter S, Ahmad Dar Z, Akbar F, Ansari V, Ascencio M V, Sajjad Athar M, Bashyal A, Bellantoni L, Bercellie A, Betancourt M, Bodek A, Bonilla J L, Bravar A, Budd H, Caceres G, Cai T, Díaz G A, da Motta H, Dytman S A, Felix J, Fields L, Filkins A, Fine R, Gallagher H, Ghosh A, Gilligan S M, Gran R, Granados E, Harris D A, Henry S, Jena D, Jena S, Kleykamp J, Klustová A, Kordosky M, Last D, Lozano A, Lu X-G, Maher E, Manly S, Mann W A, Mauger C, McFarland K S, Messerly B, Miller J, Moreno O, Morfín J G, Naples D, Nelson J K, Nguyen C, Olivier A, Paolone V, Perdue G N, Plows K-J, Ransome R D, Ruterbories D, Schellman H, Su H, Sultana M, Syrotenko V S, Valencia E, Vaughan N H, Waldron A V, Yaeggy B, Zazueta L
Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato 36000, Guanajuato, Mexico.
Phys Rev Lett. 2023 Aug 4;131(5):051801. doi: 10.1103/PhysRevLett.131.051801.
MINERvA has measured the ν_{μ}-induced coherent π^{+} cross section simultaneously in hydrocarbon (CH), graphite (C), iron (Fe), and lead (Pb) targets using neutrinos from 2 to 20 GeV. The measurements exceed the predictions of the Rein-Sehgal and Berger-Sehgal PCAC based models at multi-GeV ν_{μ} energies and at produced π^{+} energies and angles, E_{π}>1 GeV and θ_{π}<10°. Measurements of the cross-section ratios of Fe and Pb relative to CH reveal the effective A scaling to increase from an approximate A^{1/3} scaling at few GeV to an A^{2/3} scaling for E_{ν}>10 GeV.
MINERvA实验使用能量在2至20 GeV的中微子,同时测量了在碳氢化合物(CH)、石墨(C)、铁(Fe)和铅(Pb)靶中由νμ引发的相干π+截面。在多GeV的νμ能量以及产生的π+能量和角度(Eπ>1 GeV且θπ<10°)下,测量结果超出了基于Rein-Sehgal和Berger-Sehgal PCAC模型的预测。Fe和Pb相对于CH的截面比测量结果表明,有效A标度从几GeV时近似的A1/3标度增加到Eν>10 GeV时的A2/3标度。