We calculate the atmospheric flux of prompt neutrinos, produced in decays of the charmed particles at energies beyond 1 TeV. Cross sections of the $D$-mesons and ${Lambda}^{+}_{c}$ baryons production in pA and $pi$A collisions are calculated in the phenomenological quark-gluon string model (QGSM) which is updated using of the recent measurements of cross sections of the charmed meson production in the LHC experiments. A new estimate of the prompt atmospheric neutrino flux is obtained and compared with the limit of the IceCube experiment as well as with predictions of other charm production models.
We present predictions for the prompt-neutrino flux arising from the decay of charmed mesons and baryons produced by the interactions of high-energy cosmic rays in the Earths atmosphere, making use of a QCD approach on the basis of the general-mass variable-flavor-number scheme for the description of charm hadroproduction at NLO, complemented by a consistent set of fragmentation functions. We compare the theoretical results to those already obtained by our and other groups with different theoretical approaches. We provide comparisons with the experimental results obtained by the IceCube Collaboration in two different analyses and we discuss the implications for parton distribution functions.
We evaluate the prompt atmospheric neutrino flux including nuclear correction and $B$ hadron contribution in the different frameworks: NLO perturbative QCD and dipole models. The nuclear effect is larger in the prompt neutrino flux than in the total charm production cross section, and it reduces the fluxes by $10% - 30%$ depending on the model. We also investigate the uncertainty using the QCD scales allowed by the charm cross section data from RHIC and LHC experiments.
Within the Quark-Gluon String Model A.B. Kaidalov found a behaviour of quark and diquark fragmentation functions for $zrightarrow 0$ and $zrightarrow 1$, and proposed interpolation formulae for the functions in the whole region of $z$. These functions must be a solution of the well-known system of the integral equations. A simplified Monte Carlo estimation of the functions, based on usage of the fragmentation functions at $zrightarrow 1$ as the kernel functions of the system, does not reproduce Kaidalovs results. An improvement of the Monte Carlo simulations is proposed in this paper. It can be implemented in Monte Carlo event generators such as Los Alamos QGSM, QGSJet-II and the Geant4 QGS model. It will improve a description of experimental data in the models, especially, the description of the latest NA61/SHINE Collaboration data on $pi{rm C}$ interactions. Description of the data is a problem in DPMJet, QGSJet, EPOS and Sibyll models.
We evaluate the prompt atmospheric neutrino flux using the different QCD models for heavy quark production including the $b$ quark contribution. We include the nuclear correction and find it reduces the fluxes by $10 % - 50%$ according to the models. Our heavy quark results are compared with experimental data from RHIC, LHC and LHCb.
The search for stable heavy exotic hadrons is a promising way to observe new physics processes at collider experiments. The discovery potential for such particles can be enhanced or suppressed by their interactions with detector material. This paper describes a model for the interactions in matter of stable hadrons containing an exotic quark of charges $pm {1/3}e$ or $pm {2/3}e$ using Regge phenomenology and the Quark Gluon String Model. The influence of such interactions on searches at the LHC is also discussed.