14042487
Prediction for unintegrated parton distributions
Unintegrated parton distributions in the proton and nucleus are predicted by a modified Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) equation incorporating the shadowing corrections, which include exact energy-momentum conservation in each splitting and fusion vertices. We find that the nuclear shadowing effects are obvious, although they are far from the saturation limit. On the other hand, we point out that the suppression of the unintegrated gluon distribution toward lower k{sub t}{sup 2} may arise from the valence-like input rather than the saturation effects.
118390841
Particle multiplicities at LHC and deviations from limiting fragmentation
The pseudorapidity density of charged particles produced at LHC collisions are predicted by using two complementary production mechanisms with a set of consistent integrated and unintegrated parton distributions. We discuss the limiting fragmentation hypothesis and its possible violation, and we compare our model with other partonic models.
124870414
Antishadowing Corrections in the Evolution Equation of Quark Distributions
We introduce the antishadowing effect to restore the momentum sum rule in the quantum chromodynamics evolution equation for quarks in small x region.
119186907
Are valence quarks rotating
We suggest to compare the deep inelastic scattering structure functions measured in the unpolarized charged-lepton scattering off a transversely polarized proton and off a longitudinally polarized proton at larger Bjorken variable $x$, one may get a direct evidence concerning the valence quark orbital angular momentum in the proton. This possible rotating effect is estimated by using a proton-ensemble model.
122554827
Antishadowing contribution to the small x behavior of the gluon distribution
Abstract We introduce antishadowing into the Gribov-Levin-Ryskin evolution equation and restore the momentum sum rule. It is found clearly that antishadowing will modify the shadowing effect in the region 10 −4 x −2 when a hot spot with small radius exists in the nucleon.
121492263
Antishadowing properties in the small-x region
Abstract The properties of the modified Gribov-Levin-Ryskin evolution equation which incorporates both shadowing and antishadowing are analyzed. We find that some important conclusions of the GLR equation should be rewritten.
119226266
Cold stream stability during minor mergers
We use high-resolution Eulerian simulations to study the stability of cold gas flows in a galaxy size dark matter halo (10(12) M-circle dot) at redshift z = 2. Our simulations show that a cold stream penetrating a hot gaseous halo is stable against thermal convection and Kelvin-Helmholtz instability. We then investigate the effect of a satellite orbiting the main halo in the plane of the stream. The satellite is able to perturb the stream and to inhibit cold gas accretion towards the centre of the halo for 0.5 Gyr. However, if the supply of cold gas at large distances is kept constant, the cold stream is able to re-establish itself after 0.3 Gyr. We conclude that cold streams are very stable against a large variety of internal and external perturbations.