Using the analytical expression for transverse momentum dependent (TMD) gluon density in a proton, a self-consistent simultaneous description of low Q2 data on proton structure function F2(x,Q2), ...reduced cross section for the electron-proton deep inelastic scattering at HERA and soft hadron production in pp collisions at the LHC is achieved in the framework of color dipole approach and modified quark-gluon string model.
The study of
e
+
e
−
-pairs production in n-p interactions was carried out at HADES set-up due to irradiation of proton target by deuteron beam at
T
k
i
n
d
=
2
.
5
AGeV. The momentum and angular ...distributions of proton-spectator an effective masses of
e
+
e
−
-pairs were satisfactory described by a sum of various reactions of quasi-free n-p and p-p interactions.
To describe the data on hadron production at high energies in the midarapidity region and not large transverse momenta
p
T
, we modify the simple exponential form of the
p
T
-spectrum. The hadron
p
T
...-spectrum is presented in two parts due to the contributions of quarks and gluons, each of them has different energy dependence. The suggested approach alows us to describe rather satisfactorily the inclusive spectra of hadrons produced in
p
p
collisions at energies from the AGS up to LHC.
We study the role of the non-perturbative input to the transverse momentum dependent (TMD) gluon density in hard processes at the LHC. We derive the TMD gluon distribution from the fit of the ...inclusive hadron spectra measured at low transverse momenta in
p
p
collisions at the LHC and demonstrate that the best description of these spectra for larger hadron transverse momenta can be achieved by matching the derived TMD gluon distribution with the exact solution of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation obtained at small transverse momenta outside the saturation region. A special attention is put to the phenomenological applications of presented TMD parton densities to some LHC processes, which are sensitive to the quark and gluon content of a proton.
The inclusive spectra of pions and kaons produced in
BeBe
collisions as functions of their transverse momentum
p
T
at mid-rapidity are calculated within the approach, which is based on the assumption ...of the similarity of inclusive spectra of hadrons produced in
AA
collisions at their small transverse momenta in the mid-rapidity region. The essence of the modification of the self-similarity approach consists in the inclusion of a quark-gluon dynamics in hadron production in nucleon–nucleon interaction at mid-rapidity. We focus mainly on the ratio of cross-sections of
K
±
to
π
±
mesons produced in
BeBe
collisions as a function of
s
. A fast rise of this ratio, when the initial energy increases starting from the kaon production threshold up to
s
≃
20–30 GeV, is revealed together with its very slow increase up to LHC energies. The energy dependence of this ratio is due to the conservation laws of four-momenta and quantum numbers of the initial and produced hadrons and the Regge asymptotic behavior of the total and inelastic cross-sections of nucleon–nucleon collisions at large initial energies The satisfactory description of NA61/SHINE data on these ratios is demonstrated. Some predictions for RHIC and LHC on the
K
+
/
π
+
and
K
-
/
π
-
yield ratios as functions of
s
in
BeBe
collisions as functions of
s
are presented. The similarity of these observables to the ones for
pp
collisions at mid-rapidity and in the wide range of initial energies is illustrated.
We update the phenomenological parameters of the Transverse Momentum Dependent (TMD, or unintegrated) gluon density in a proton proposed in our previous studies. This analysis is based on the ...analytical expression for starting gluon distribution which provides a self-consistent simultaneous description of HERA data on proton structure function F 2 ( x , Q 2 ), reduced cross section for the electron-proton deep inelastic scattering at low Q 2 and soft hadron production in pp collisions at the LHC conditions. We extend it to the whole kinematical region using the Catani–Ciafaloni–Fiorani–Marchesini (CCFM) evolution equation. Exploiting our previous results on a number of semihard QCD processes, we performed a combined fit to an extended set of LHC and HERA data, comprising a total of 509 points from 16 data sets. We illustrate our fit by applying the derived TMD gluon density in a proton to inclusive prompt photon photoproduction at HERA.
The LHC with pp-collisions at radicals = 7-14 TeV will obviously supply extra unique information concerning the non-zero intrinsic (or valence-like) heavy quark component of the proton distribution ...functions component of the proton. On the basis of theoretical study it is demonstrated that investigaton of the intrinsic heavy quark contributions looks very promising at the LHC in processes like pp arrow right y + c(b) + X.
We update the phenomenological parameters of the Transverse Momentum Dependent (TMD, or unintegrated) gluon density in a proton proposed in our previous studies. This analysis is based on the ...analytical expression for starting gluon distribution which provides a self-consistent simultaneous description of HERA data on proton structure function \(F_2(x,Q^2)\), reduced cross section for the electron-proton deep inelastic scattering at low \(Q^2\) and soft hadron production in \(pp\) collisions at the LHC conditions. We extend it to the whole kinematical region using the Catani-Ciafaloni-Fiorani-Marchesini (CCFM) evolution equation. Exploiting our previous results on a number of semihard QCD processes, we performed a combined fit to an extended set of LHC and HERA data, comprising a total of \(509\) points from \(16\) data sets. We illustrate our fit by applying the derived TMD gluon density in a proton to inclusive prompt photon photoproduction at HERA.
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