129 research outputs found
Are multiple parton interactions important at high energies? New types of hadrons production processes
Hadrons interaction at high energies is carried out by one color gluon
exchange. All quarks and gluons contained in colliding hadrons take part in
interaction and production of particles. The contribution of multiple parton
interactions is negligible. Multiple hadrons production at high energies occurs
only in three types of processes. The first process is hadrons production in
gluon string, the second is hadrons production in two quark strings and the
third is hadrons production in three quark strings. In proton-proton
interaction production of only gluon string and two quark strings is possible.
In proton-antiproton interaction production of gluon string, two quark strings
and three quark strings is possible. Therefore multiplicity distributions in
proton-proton and proton-antiproton interactions are different.Comment: Talk given at ISMD 2009 conference, 5 pages, 8 figure
Elliptic flow orientation, saturation and low behavior
We consider general model with factorization between macroscopic flow and
matter decay distribution. We show universality of behavior of elliptic
flow at small for identified final particles in the symmetric nucleus
collision. At high we compare non-relativistic and relativistic models
for boosted decay distribution. In the relativistic models with distribution
having power-like tail we show existence of elliptic flow saturation. This
means that the elliptic flow value tend to constant at high . We
discuss the importance of determination of elliptic flow orientation which can
help us to compare different models. For example, we introduce potential
expansion model which can reproduce azimuthal asymmetry but based on the
assumption that there are only cold strong forces and no thermalization. This
model show opposite sign of elliptic flow orientation in comparison with
thermal model. We also show that at small sign of elliptic flow can
change due to sign of second derivative of decay distribution. This fact tell
us that we must more carefully link elliptic flow sign and properties of the
model.Comment: Latex2e, 11 pages, 1 figur
Multipomeron quasi-eikonal model for single diffraction processes
Single diffraction processes was usually treated in the triple-reggeon
framework, but this formalism is inconsistent with CDF data. In this paper we
show, that multipomeron quasi-eikonal model gives agreement with these data.
Cross-section of single diffraction processes at LHC energy is estimated.Comment: 5 pages, 3 figures, LTeX2
Advanced rapidity gap trigger
Nubmer of physically interesting processes is charachterized by the rapidity
gaps. In reality, this gaps is filled by uderlying events with high (more than
0.75 for higgs) probability. In this paper we purpose a way to detect this
shadowed events with aim to raise the number of rare events.Comment: 5 pages, 2 figure
Possible improvements of higgs trigger at LHC
In this work we consider two ways to improve signal to background
cross-sections ratio for higgs searchings at LHC: likelyhood method and
advanced rapidity trigger. Both methods are universal enough, likelyhood method
can be applied to any processes with many observables, and advanced rapidity
trigger can separate any colourless scattering processes and processes with
colour charge at channel
Possible difference between multiplicity distributions and inclusive spectra of secondary hadrons in proton-proton and proton-antiproton collisions at energy sqrt(s)=900 GeV
We consider QCD based model of hadrons interaction in which gluons density in
wave function of initial state is low in rapidity space and real hadrons are
produced by decay of color field strings. Hadrons production processes in pp
and p antip interactions differ on principle. There are three types of
inelastic processes in p antip collision. The first type is production of
secondary hadrons shower from decay of gluon string. The second type is shower
produced from decay of two quark strings and the third one -- from decay of
three quark strings. At the same time there are only two types of inelastic
processes for pp collision, they are shower from gluon string and shower from
two quark strings. Therefore multiplicity distributions and inclusive spectra
of secondary hadrons are different in pp and p antip interactions, and this
difference may be observed at energy sqrt(s)=900 GeV.Comment: 12 pages, 13 figure
Total cross section of neutron-proton scattering at low energies in quark-gluon model
We show that analysis of nonrelativistic neutron-proton scattering in a
framework of relativistic QCD based quark model can give important information
about QCD vacuum structure. In this model we describe total cross section of
neutron-proton scattering at kinetic energies of projectile neutron from 1 eV
up to 1 MeV.Comment: 8 pages, 4 figure
KNO scaling in processes of electron-positron annihilation to hadrons
The charged particles multiplicity distribution in the KNO form is discussed
in processes of annihilation at energies 14 -- 206.2 GeV.
The experimental data are compared to data, obtained with Monte Carlo
simulation in PYTHIA in the Lund quark string model. It is shown, that both
experimental and simulated data are described by the same distribution function
in the KNO form. It is shown, that the KNO scaling is consequence of quark
string hadronization dynamics in the Lund string model.Comment: 11 pages, 5 figure
Color Diagrams for Non Vacuum Reggeons in Hadron-Hadron Interactions
One-to-one correspondence between dual diagrams of dual resonance model and
QCD based color diagrams describing non vacuum exchanges in pi+ pi-, pi+- p, p
anti p interactions is discussed. Both for dual and color diagrams there are
state with quark-antiquark in t channel and state, in which only coherent quark
string exists, in s channel. There are no such dual diagrams in pp interaction.
Color diagram for pp interaction was found basing on principle of conformity.
Secondary hadrons spectrum, obtained from this diagram, has nucleon in its
central region. This effect may lead to increase of baryon chemical potential
in nucleus-nucleus collisions in facilities NICA and FAIR.Comment: 9 pages, 13 figure
Cronin momentum behavior in saturation model for , , collisions
In this paper we consider Cronin momentum behaviour for , and
collisions in saturation model. Our analysis shows that Cronin momentum
behavior at different rapidities and energies, can be related with scaling law
using simple dimensional consideration. Using exact numerical solution of
Balitsky-Kovchegov equation we show that although this dependence is slightly
different for McLerran-Venugopalan and Balitsky-Kovchegov definition of gluon
distribution function in simple model in this case dependencies is almost the
same (i.e ratio of Cronin momentum calculated using these gluon distribution
functions is big constant). This can be used to experimentally distinguish this
two variant of gluon distribution function definition in saturation model and
choose the right one.Comment: 15 pages, 6 figure
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