Speaker
Sergio Scopetta
(Perugia University)
Description
The time reversal-odd parton transverse momentum distributions (TMDs) [1]
in the neutron will be studied through polarized SIDIS experiments off 3He, where a high-energy pion is detected in coincidence with the scattered electron (see for example [2]). To disentangle the nuclear and the partonic degrees of freedom an accurate theoretical description of the process is needed. In Ref. [3] the plane wave impulse approximation (IA) was adopted. It was found that the nuclear effects described in IA can be taken into account in a simple effective way, and a procedure to safely extract the neutron SSAs was proposed. In a recent paper [4] the spectator SIDIS process off 3He was studied, and the final state interaction (FSI) between the hadronizing quark and a recoiling deuteron was taken into account through a distorted spin-dependent spectral function. We are now studying the standard SIDIS process, where the FSI between the observed pion and the remnant is again taken into account through a distorted spin-dependent spectral function [5]. The result, very interesting in particular for the experiments planned at the 12 GeV upgrade of JLab [2], is that in the nuclear SSA the effect of FSI cancels to a large extent and the ususal extraction appears to be safe.
An extension of the approach to a relativistic treatment will be addressed [6].
REFERENCES
[1] V. Barone, F. Bradamante, a. Martin Prog. Part. Nucl. Phys. 65, 267, 2010.
[2] G. Cates et al., E12-09-018, JLAB approved experiment,
hallaweb.jlab.org/collab/PAC/PAC38//E12-09-018-SIDIS.pdf
[3] S. Scopetta, Phys. Rev. D 75, 054005 (2007).
[4] L.P. Kaptari, A. Del Dotto, E. Pace, G. Salme` and S. Scopetta, Phys. Rev. C 89, 035206 (2014).
[5] A. Del Dotto, L. Kaptari, E. Pace, G. Salme` and S. Scopetta, in preparation.
[6] E. Pace, G. Salme`, S. Scopetta, A. Del Dotto and M. Rinaldi, Few Body Syst. 54, 1079 (2013); A. Del Dotto, L.P. Kaptari, E. Pace, G., Sergio Scopetta, Few-Body Syst. 55, 877 (2014).
| Session | 4: TMDs from azimuthal asymmetries in polarized SIDIS with transverse and longitudinal spin |
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Author
Sergio Scopetta
(Perugia University)
Co-authors
Alessio Del Dotto
(University of Rome-3)
Emanuele Pace
(University of Rome-2, Torvergata, and INFN)
Giovanni Salme'
(INFN Roma)
Leonid Kaptari
(JINR Dubna, Russia)
Matteo Rinaldi
(Perugia University and INFN)
