Transverse target spin asymmetry in inclusive DIS with two-photon exchange
| dc.creator | Afanasev, A. | |
| dc.creator | Strikman, M. | |
| dc.creator | Weiss, C. | |
| dc.date | 2007-09-06 | |
| dc.date.accessioned | 2026-07-07T11:42:17Z | |
| dc.date.available | 2026-07-07T11:42:17Z | |
| dc.description | We study the transverse target spin dependence of the cross section for inclusive electron-nucleon scattering with unpolarized beam. Such dependence is absent in the one-photon exchange approximation (Christ-Lee theorem) and arises only in higher orders of the QED expansion, from the interference of one-photon and absorptive two-photon exchange amplitudes as well as from real photon emission (bremsstrahlung). We demonstrate that the transverse spin-dependent two-photon exchange cross section is free of QED infrared and collinear divergences. We argue that in DIS kinematics the transverse spin dependence should be governed by a "parton-like" mechanism in which the two-photon exchange couples mainly to a single quark. We calculate the normal spin asymmetry in an approximation where the dominant contribution arises from quark helicity flip due to interactions with non-perturbative vacuum fields (constituent quark picture) and is proportional to the quark transversity distribution in the nucleon. Such helicity-flip processes are not significantly Sudakov-suppressed if the infrared scale for gluon emission in the photon-quark subprocess is of the order of the chiral symmetry breaking scale, mu_chiral^2 >> Lambda_QCD^2. We estimate the asymmetry in the kinematics of the planned Jefferson Lab Hall A experiment to be of the order 10^{-4}, with different sign for proton and neutron. We also comment on the spin dependence in the limit of soft high-energy scattering. | |
| dc.description | 22 pages, 14 figures; uses revtex4 | |
| dc.identifier | https://arxiv.org/abs/0709.0901 | |
| dc.identifier | http://arxiv.org/abs/0709.0901 | |
| dc.identifier | Phys.Rev.D77:014028,2008 | |
| dc.identifier | doi:10.1103/PhysRevD.77.014028 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/200832 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | Transverse target spin asymmetry in inclusive DIS with two-photon exchange | |
| dc.type | text |