Deeply virtual compton scattering off the neutron

M. Mazouz (1) , A. Camsonne (2) , C. Munoz Camacho (3) , C. Ferdi (2) , G. Gavalian , E. Kuchina , M. Amarian , K.A. Aniol , M. Beaumel (3) , H. Benaoum , P.Y. Bertin (2) , M. Brossard (2) , J.-P. Chen , E. Chudakov , B. Craver , F. Cusanno , C.W. de Jager , A. Deur , R. Feuerbach , J.-M. Fieschi (2) , S. Frullani , M. Garcon (3) , F. Garibaldi , O. Gayou , R. Gilman , J. Gomez , P. Gueye (2) , P.A.M. Guichon (3) , B. Guillon (1) , O. Hansen , D. Hayes , D. Higinbotham , T. Holmstrom (3) , C. E. Hyde (2) , H. Ibrahim , R. Igarashi , X. Jiang , H.S. Jo (4) , L.J. Kaufman , A. Kelleher (3) , A. Kolarkar , G. Kumbartzki , G. Laveissiere (2) , J.J. Lerose , R. Lindgren , N. Liyanage , H.-J. Lu , D.J. Margaziotis , Z.-E. Meziani , K. Mccormick , R. Michaels , B. Michel (2) , B. Moffit (3) , P. Monaghan , S. Nanda , V. Nelyubin , M. Potokar (2) , Y. Qiang , R.D. Ransome , J.S. Réal (1) , B. Reitz , Y. Roblin , J. Roche , F. Sabatie (3) , A. Saha , S. Sirca (2) , K. Slifer , P. Solvignon , R. Subedi (2) , V. Sulkosky (3) , P.E. Ulmer , E. Voutier (1) , K. Wang , L.B. Weinstein , B. Wojtsekhowski , X. Zheng (2) , L. Zhu

1 LPSC - Laboratoire de Physique Subatomique et de Cosmologie
2 LPC - Laboratoire de Physique Corpusculaire - Clermont-Ferrand
3 DAPNIA - Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée
4 IPNO - Institut de Physique Nucléaire d'Orsay

The present experiment exploits the interference between the Deeply Virtual Compton Scattering (DVCS) and the Bethe-Heitler processes to extract the imaginary part of DVCS amplitudes on the neutron and on the deuteron from the helicity-dependent D$({\vec e},e'\gamma)X$ cross section measured at $Q^2$=1.9 GeV$^2$ and $x_B$=0.36. We extract a linear combination of generalized parton distributions (GPDs) particularly sensitive to $E_q$, the least constrained GPD. A model dependent constraint on the contribution of the up and down quarks to the nucleon spin is deduced.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

M. Mazouz, A. Camsonne, C. Munoz Camacho, C. Ferdi, G. Gavalian, et al.. Deeply virtual compton scattering off the neutron. Physical Review Letters, 2007, 99, pp.242501. ⟨10.1103/PhysRevLett.99.242501⟩. ⟨in2p3-00169804⟩