相关论文: Impact of saturation on s-channel helicity noncons…
I review the recent progress in the theory of s-channel helicity nonconservation (SCHNC) effects in diffractive DIS. SCHNC in diffractive vector meson production is an unique probe of the spin-orbit coupling and Fermi motion of quarks in…
We derive a full set, and determine the twist, of helicity amplitudes for diffractive production of light to heavy vector mesons in deep inelastic scattering. For large $Q^{2}$ all helicity amplitudes but the double-flip are calculable in…
I review new results on s-channel helicity nonconservation (SCHNC) in diffractive DIS. I discuss how by virtue of unitarity diffractive DIS gives rise to spin structure functions which were believed to vanish at x << 1. These include tensor…
We investigate saturation effects in exclusive vector meson production in deep inelastic scattering (DIS), where we model fluctuations within the target protons as localized color-charge hotspots. Based on the Color Glass Condensate (CGC)…
I review the recent progress in the theory of s-channel helicity nonconservation (SCHNC) effects in diffractive DIS including the unitarity driven demise of the Burkhardt-Cottingham sum rule and strong scaling departure from the…
In this work the production of vector mesons in diffractive DIS is analyzed, with an emphasis on the impact of the internal spin structure of a vector meson upon its virtual photoproduction rate. We derived the full sets of s-channel…
Within the limits of the large-N_c approximation (with N_c the number of colors), we establish the high-energy behaviour of the diffractive and inclusive cross-sections for deep inelastic scattering at fixed impact parameter. We demonstrate…
The Lorentz contraction of ultrarelativistic nuclei entails a spatial overlap and fusion (recombination, saturation) of partons belonging to different nucleons at the same impact parameter. In these lectures we present a consistent…
In this work we present for the first time the comprehensive study of the Melosh spin rotation effects in diffractive electroproduction of S-wave heavy quarkonia off a nucleon target. Such a study has been performed within the color dipole…
We study exclusive vector meson production in ultra-peripheral collisions (UPCs) of a wide range of nuclei, and assess the potential of measurements to constrain the small-$x$ structure of oxygen and neon nuclei. We employ an…
I review the modern status of QCD theory of diffractive vector meson production with the focus on shrinkage of photons with Q2 and (Q2+mV2)$scaling, j-plane properties of the QCD pomeron and Regge shrinkage of diffraction cone, $s$-channel…
It is already known from phenomenological studies that in exclusive deep-inelastic scattering off nuclei there appears to be a scaling behavior of vector meson production cross section in both nuclear mass number, $A$, and photon…
The neutron spin-orbit density contributes to the nuclear charge density as a relativistic effect. The contribution is enhanced by the effective mass stemming from the Lorentz-scalar potential in relativistic models. This enhancement…
We consider the s-channel scattering of massive fermion or vector-boson pairs with equal helicities, mediated by a graviton in the linearized Einstein theory. We show that, although in general both spin-2 and spin-0 components are present…
The structure of the spin interaction operator (SI) (the interaction that remains after space variables are integrated out) in the first order S-matrix element of the elastic scattering of a Dirac particle in a general helicity-conserving…
We study in perturbative QCD the helicity ampltiudes of the process $\gamma^{*} p \to \rho p $ at large virtualities $Q$ of the photon $\gamma^{*}$. We estimate all spin flip amplitudes taking into account an important effect of the scale…
We propose a new description of inclusive diffraction in deep inelastic scattering (DIS). The diffractive structure functions are expressed in the dipole picture and contain heavy-quark contributions. The dipole scattering amplitude, a…
We summarize recent work in which the shell effect, which causes the onset of the mass asymmetry in nuclear fission, could be explained semiclassically in the framework of the periodic orbit theory. We also present new results for the…
We derive helicity amplitudes for diffractive leptoproduction of the S and D wave states of vector mesons. We predict a dramatically different spin dependence for production of the S and D wave vector mesons. We find very small…
We derive the two-plateau momentum distribution of final state (FS) quarks produced in deep inelastic scattering (DIS) off nuclei in the saturation regime. The diffractive plateau which dominates for small transverse momentum p measures…