Hadronic interactions: From LHC to Ultra-High Energy Cosmic Rays
Astrophysics and Astronomy
Theoretical Chemistry: Molecules, Materials, Surfaces
Final Report Abstract
The interpretation of high energy cosmic ray data and the solution of the enigma of the origin of ultra-high energy cosmic rays (UHECRs) depend crucially on the validity of hadronic Monte Carlo (MC) models which are required for the description of the interactions of cosmic ray particles in the atmosphere. The main result of the project is the development of a new MC generator of hadronic collisions, QGSJET-III, which included a phenomenological treatment of nonlinear interaction effects related to multiparton interactions and higher twist corrections to parton production. This allowed us to extend the perturbative treatment over a larger part of the relevant kinematic space and thereby enhance the predictive power of the model, which may thus have a vast range of applications in the astroparticle physics field, notably, in relation to investigations of UHECRs. On the other hand, the developed model can be used in collider physics, e.g. for studies of general minimum bias proton-proton collisions, of soft and hard diffraction, and of multi-parton interactions. Other activities performed within the scope of the project concerned a number of problems related to studies of high energy proton-proton collisions and to investigations of ultra-high energy cosmic rays. In particular, we performed calculations of the rapidity gap survival probabilities for diffractive dijet production, using the Reggeon Field Theory framework, and demonstrated that the so-called non-eikonal absorption, caused by elastic rescatterings of intermediate partons, plays a sub-dominant role, compared to the usual eikonal rescatterings between constituent partons. Additionally, we revealed a relation of MC model predictions for forward hadron spectra to the assumptions concerning the structure of constituent parton Fock states in hadrons and proposed a way to discriminate between the respective model approaches by studying correlations between signal strengths in central and forward-looking LHC detectors. We proposed also a viable astrophysical model, which is able to describe simultaneously both the spectra and nuclear composition of UHECRs, observed by the Pierre Auger Observatory, and the astrophysical neutrino flux, measured by the IceCube experiment.
Publications
- Rapidity gap survival in enhanced pomeron scheme
S. Ostapchenko and M. Bleicher
- Constraining high energy interaction mechanisms by studying forward hadron production at the LHC, Physical Review D 94, 114026 (2016)
S. Ostapchenko, M. Bleicher, T. Pierog, and K. Werner
(See online at https://doi.org/10.1103/PhysRevD.94.114026) - Constraining pion interactions at very high energies by cosmic ray data, Physical Review D 93, 051501(R) (2016)
S. Ostapchenko and M. Bleicher
(See online at https://doi.org/10.1103/PhysRevD.93.051501) - Constraints on high energy interaction models from LHC and cosmic ray data, EPJ Web of Conferences 125, 03013 (2016)
S. Ostapchenko
(See online at https://doi.org/10.1051/epjconf/201612503013) - Cosmic ray interaction models: an overview, EPJ Web of Conferences 120, 04003 (2016)
S. Ostapchenko
(See online at https://doi.org/10.1051/epjconf/201612004003) - Double parton scattering: Impact of nonperturbative parton correlations, Physical Review D 93, 034015 (2016)
S. Ostapchenko and M. Bleicher
(See online at https://doi.org/10.1103/PhysRevD.93.034015) - A minimal model for extragalactic cosmic rays and neutrinos, Physical Review D 96, 083006 (2017)
M. Kachelriess, O. Kalashev, S. Ostapchenko, and D. V. Semikoz
(See online at https://doi.org/10.1103/PhysRevD.96.083006) - A minimal model for extragalactic high energy particles, Proceeding of Science IFS2017, 176 (2017)
M. Kachelriess, O. Kalashev, S. Ostapchenko, and D. V. Semikoz
(See online at https://dx.doi.org/10.22323/1.312.0176) - Solution of heliospheric propagation: unveiling the local interstellar spectra of cosmic ray species, Astrophysical Journal 840, 115 (2017)
M. J. Boschini, S. Della Torre, M. Gervasi, D. Grandi, G. Johannesson, M. Kachelriess, G. La Vacca, N. Masi, I. V. Moskalenko, E. Orlando, S. S. Ostapchenko, S. Pensotti, T. A. Porter, L. Quadrani, P. G. Rancoita, D. Rozza, and M. Tacconi
(See online at https://doi.org/10.3847/1538-4357/aa6e4f)
