47,123 research outputs found
Odderon with a running coupling constant
The running coupling is introduced into the equation for the odderon via the
bootstrap relation. It is shown that the previously found odderon state with a
maximal intercept, which is constructed from antisymmetric pomeron wave
function, continues to exist in the running coupling case. Its intercept is
found to remain equal to unity independent of the behaviour assumed for the
running coupling at low momenta.Comment: 9 pages, LaTe
On the inclusive gluon jet production from the triple pomeron vertex in the perturbative QCD
Single and double inclusive cross-sections for gluon jet production from
within the triple pomeron vertex are studied in the reggeized gluon technique.
It is shown that to satisfy the AGK rules the vertex has to be fully symmetric
in all four reggeized gluons which form the two final pomerons. The single
inclusive cross-sections are found for different cuttings of the triple pomeron
vertex. They sum into the expression obtained by Yu.Kovchegov and K.Tuchin in
the colour dipole picture. The found double inclusive cross-sections satisfy
the AGK rules.Comment: 17 pages in LaTex, 6 figures, revised version with partially changed
rsult
BKP states in the inclusive gluon production
Inclusive cross-section for gluon production is calculated by the dispersion
technique in the NLO in the perturbative QCD with a large number of colours.
The found cross-section coincides with the one derived in the dipole picture.
No trace of the BKP states is found.Comment: 30 pages, 17 figures. Appendix with a new observation added.
Conclusions changed
Loops in the gluon emission amplitude: reggeization from the Glauber scattering
It is shown that in the Glauber scattering of a fast quark in the external
field loop corrections to the gluon emission amplitude due to virtual softer
gluon after renormalization coincide with a correction due to reggeization of
the exchanged gluon in the BFKL picture.Comment: 26 pages, 10 figure
On the initial condition for evolution of the perturbative QCD Pomeron in the nucleus
It is shown that subdominant terms found in the reggeized gluon diagram
technique, to be added to Pomeron fan diagrams with the 3P interaction, can be
exactly taken into account by taking the initial condition for evolution in the
Glauber form. This demonstrates complete equivalence of the dipole picture and
the reggeized gluon approach not only on the leading level but also on the
subleading level.Comment: 5 pages in LaTe
Three Generations on the Quintic Quotient
A three-generation SU(5) GUT, that is 3x(10+5bar) and a single 5-5bar pair,
is constructed by compactification of the E_8 heterotic string. The base
manifold is the Z_5 x Z_5-quotient of the quintic, and the vector bundle is the
quotient of a positive monad. The group action on the monad and its
bundle-valued cohomology is discussed in detail, including topological
restrictions on the existence of equivariant structures. This model and a
single Z_5 quotient are the complete list of three generation quotients of
positive monads on the quintic.Comment: 19 pages, LaTeX. v2: section on anomaly cancellation adde
The Reggeon 2 Reggeons Particle vertex in the Lipatov effective action formalism
The vertex for gluon emission during the splitting of a reggeized gluon into
two is constructed in the framework of Lipatov effective action formalism. Its
reduction to a pure transverse form for the diffractive amplitude gives the
standard Bartels vertex plus an additional contribution corresponding to the
emission from a pointlike splitting vertex. This additional contribution turns
out to be given by a longitudinal integral divergent both in the ultraviolet
and infrared. A certain specific recipe for this part, including the principal
value prescription for the integration, allows to eliminate this unwanted
contribution.Comment: 4 figures; misprints corrected; to be published in Eur.Phys.J.
Cumulative particle production as a rare event
The generalization of the Glauber formula for cumulative production events is
derived. On its basis the multiplicity distribution in such events is related
to the one in the minimum bias events. As compared to the rare events of type
, the formula involves a shift in the arguments determined by the
multiplicity from a collision with a cluster of several nucleons.Comment: 11 pages, LaTe
Statistical hadronization of charm at SPS, RHIC and LHC
We study the production of charmonia and charmed hadrons for nucleus-nucleus
collisions at SPS, RHIC, and LHC energies within the framework of the
statistical hadronization model. Results from this model are compared to the
observed centrality dependence of J/psi production at SPS energy. We further
provide predictions for the centrality dependence of the production of open and
hidden charm mesons at RHIC and LHC.Comment: Contribution to Quark Matter 2002, 4 pages, 3 figures; revised
version including charmed hyperons (omitted in v1
Probing the Phase Boundary between Hadronic Matter and the Quark-Gluon-Plasma in Relativistic Heavy Ion Collisions
We discuss recent data on particle production with emphasis on the degree of
thermal and chemical equilibration achieved. The data are interpreted in terms
of a resonance gas model. The phase boundary constructed between the resonance
gas and the quark-gluon plasma is shown to be very close to the deduced
parameters characterizing the hadronic fireball at freeze-out.Comment: 7 pages, latex, 6 figures, 1 table submitted to Nuclear Physics A,
dedicated to Gerry Brown in honor of his 70th birthda
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