Leading twist nuclear shadowing, nuclear generalized parton distributions, and nuclear deeply virtual Compton scattering at small x

Journal Article · Sun Mar 15 04:00:00 EDT 2009 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.79.035210· OSTI ID:21199638

Goeke, K ^[1]; Guzey, V ^[2]; Siddikov, M ^[1]

---

1. Institut fuer Theoretische Physik II, Ruhr-Universitaet-Bochum, D-44780 Bochum (Germany)
2. Theory Center, Jefferson Laboratory, Newport News, Virginia 23606 (United States)

We generalize the leading twist theory of nuclear shadowing and calculate quark and gluon generalized parton distributions (GPDs) of spinless nuclei. We predict very large nuclear shadowing for nuclear GPDs. In the limit of the purely transverse momentum transfer, our nuclear GPDs become impact-parameter-dependent nuclear parton distribution functions (PDFs). Nuclear shadowing induces nontrivial correlations between the impact parameter b and the light-cone fraction x. We make predictions for the deeply virtual Compton scattering (DVCS) amplitude and the DVCS cross section on {sup 208}Pb at high energies. We calculate the cross section of the Bethe-Heitler (BH) process and address the issue of the extraction of the DVCS signal from the eA{yields}e{gamma}A cross section. We find that the eA{yields}e{gamma}A differential cross section is dominated by DVCS at the momentum transfer t near the minima of the nuclear form factor. We also find that nuclear shadowing leads to dramatic oscillations of the DVCS beam-spin asymmetry, A{sub LU}, as a function of t. The position of the points where A{sub LU} changes sign is directly related to the magnitude of nuclear shadowing.

• OSTI ID: 21199638
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 3 Vol. 79; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ASYMMETRY
BETHE-HEITLER THEORY
COMPTON EFFECT
CORRELATIONS
DIFFERENTIAL CROSS SECTIONS
DISTRIBUTION
DISTRIBUTION FUNCTIONS
EXTRACTION
FORECASTING
FORM FACTORS
GLUONS
IMPACT PARAMETER
LEAD 208
LIGHT CONE
MOMENTUM TRANSFER
OSCILLATIONS
QUARKS
SPIN
TRANSVERSE MOMENTUM