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

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

KNO scaling in processes of electron-positron annihilation to hadrons

The charged particles multiplicity distribution in the KNO form is discussed in processes of $e^+e^-$ annihilation at energies $\sqrt{s}$ 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

Inclusive cross sections of proton-proton and proton-antiproton scattering

We have predicted the difference in inclusive cross sections on pseudorapidity in ${\rm d}\sigma^{p\bar{p}}/{\rm d}\eta$ and ${\rm d}\sigma^{pp}/{\rm d}\eta$ interactions at $\sqrt{s}=900$~GeV. Their ratio $R=\left({\rm d}\sigma^{p\bar{p}}/{\rm d}\eta\right)\left/\left({\rm d}\sigma^{pp}/{\rm d}\eta\right)\right.>1$ in the whole pseudorapidity range. On the basis of AGK theorem we show that the ratio of inclusive cross sections of $pp$ and $p\bar{p}$ at $\sqrt{s}=900$~GeV in the region of low transverse momenta $p_\perp$ up to 2~GeV $\left(\frac{1}{2\pi p_\perp}\frac{{\rm d}^2\sigma^{p\bar{p}}}{{\rm d}\eta {\rm d}p_\perp}\right)\left/\left(\frac{1}{2\pi p_\perp}\frac{{\rm d}^2\sigma^{pp}}{{\rm d}\eta {\rm d}p_\perp}\right)\right.=R$. Experimental measurements by the ATLAS Coll. give value $R\simeq1.2$ for interval $|\eta|<2.5$. The difference in inclusive cross sections results from presence of additional subprocess in $p\bar{p}$ -- hadrons production from decay of three quark strings, which is absent in $pp$ scattering.Comment: Talk presented at the ISMD 2010, Antwerp (Belgium). Some typos are correcte

Experimental evidences of difference in pppp and ppˉp\bar{p} interactions at high energies

Hadrons production is different in $p\bar{p}$ and $pp$ interactions at high energies. There is process of hadrons production from three quark strings in $p\bar{p}$ which is absent in $pp$. This process grows as $(\ln\sqrt{s})^2$ and becomes significant when energy of collision increases. Inclusive cross sections of $p\bar{p}$ interaction exceed inclusive cross sections of $pp$. Theoretical estimation of the ratio of $p\bar{p}$ to $pp$ at energy $\sqrt{s}=900$ GeV gives $R=1.12\pm0.03$. The UA1 data on $p\bar{p}$ transverse momentum distribution are about 1.2 -- 1.3 times higher than the CMS, ATLAS and ALICE data on $pp$ at energy $\sqrt{s}=900$ GeV.Comment: 16 pages, 4 figures, preprint submitted to Physics Letters

Nucleus-Nucleus Collisions at Low Energies. The Effects from Non Vacuum Exchange

Experimental data on total and differential elastic cross sections for $p+p(\bar{p})$, $n+p(\bar{p})$, $K^\pm+p$, $K^\pm+n$, $\pi^\pm+p$ starting from energy 3.5 GeV in CMS are used to determine parameters of vacuum contribution and parameters of basic non vacuum reggeons: $f$, $\omega$, $\rho$ and $A_2$. It is argued that non vacuum contributions to proton-proton and proton-neutron collisions correspond to spectrum in which baryon number is moved from the fragmentation region to central region in rapidity space. In this case it is possible that chemical potential is increased in central region of spectrum of nucleus-nucleus interaction at low energies. This effect might be important for facilities FAIR and NICA

Multiplicity Distribution of Secondary Hadrons at LHC Energy and Total Cross Sections of Hadron-Hadron Interactions

The multiple production processes of secondary hadrons in proton-antiproton scattering are divided into three types. The first type is a shower of secondary hadrons produced from gluon string decay, the second type is a shower of secondary hadrons produced from two quark strings decay and the third is a shower produced from three quark strings decay. At the same time there are only two types for proton-proton scattering - shower from gluon string and shower from two quark strings. These showers do not correspond to pomeron showers originating from cuts of one, two, three, ... pomerons. Multiplicity distribution in gluon string is Gaussian, in two and three quark strings it is negative binomial. Gluon string weight in the multiplicity distribution is determined by the constant contribution to total cross sections, the quark strings weights - by the growing with energy contributions. The expected value of proton-proton scattering total cross section and the multiplicity distribution at energy 14 TeV are givenComment: 17 pages, 26 figure

Soft colour interactions in hadron-hadron hard diffraction

SCI model gives a good and natural description of DDIS cross-sections. Howevere, this model is pure phenomenological, and does not explain the nature of soft color rearrangment. In this paper we argue, that the most capabilities of SCI model can be derived from low constituent model and overview applicability of low constituent model to DDIS processes.Comment: 5 pages, 3 figure

A crystal cleavage mechanism for UHV STM

A device for UHV cleavage of crystal specimens for the use with STM has been suggested and developed. We present a device suitable for the precise cleavage of semiconductors. The device needs only small space and can be easily mounted in a small and compact UHV chamber equipped with a wobble stick manipulator. In order to prove the technique UHV STM measurements on InAs(110) surfaces with different bulk conductivities (p-and n-type) have been performed.Comment: 6 pages, 3 figure