https://doi.org/10.1140/epja/s10050-021-00580-y
Regular Article - Theoretical Physics
Deeply virtual Compton scattering off Helium nuclei with positron beams
1
Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Perugia, Italy
2
INFN, Sezione di Perugia, via A. Pascoli snc, 06123, Perugia, Italy
3
Old Dominion University, 23529, Norfolk, VA, USA
Received:
27
April
2021
Accepted:
26
August
2021
Published online:
15
September
2021
Positron initiated deeply virtual Compton scattering (DVCS) off 
He and 
He nuclei is described. The way the so-called 
term could be obtained from the real part of the relevant Compton form factor is summarized, and the importance and novelty of this measurement is discussed. The measurements addressed for He targets could be very useful even in a standard unpolarized target setup, measuring beam spin and beam charge asymmetries only. The unpolarized beam charge asymmetries for DVCS off He and He are also estimated, at JLab kinematics and, for He, also at a configuration typical at the future Electron–Ion Collider. Incoherent DVCS processes, in particular the ones with tagging the internal target by measuring slow recoiling nuclei, and the unique possibility offered by positron beams for the investigation of Compton form factors of higher twist, are also briefly addressed.
© The Author(s) 2021
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