English
Related papers

Related papers: Secondary Cosmic Positrons in an Inhomogeneous Dif…

200 papers

We consider the propagation of galactic cosmic rays under assumption that the interstellar medium is a fractal one. An anomalous diffusion equation in terms of fractional derivatives is used to describe of cosmic ray propagation. The…

Astrophysics · Physics 2007-05-23 A. A. Lagutin , V. V. Uchaikin

Sub-GeV dark matter candidates are of increasing interest, because long-favored candidates such as GeV-scale WIMPs have not been detected. For low-mass dark matter, model-independent constraints are weak or nonexistent. We show that for…

High Energy Physics - Phenomenology · Physics 2019-07-09 Christopher V. Cappiello , Kenny C. Y. Ng , John F. Beacom

Observations of molecular clouds in the gamma ray domain provide us with a tool to study the distribution of cosmic rays in the Galaxy. This is because cosmic rays can penetrate molecular clouds, undergo hadronic interactions in the dense…

High Energy Astrophysical Phenomena · Physics 2017-08-23 Stefano Gabici

We study the annihilating dark matter contribution to the extra-galactic diffuse gamma-ray background spectrum, motivated by the recent observations of cosmic-ray positron/electron anomalies. The observed diffuse gamma-ray flux provides…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-02 Masahiro Kawasaki , Kazunori Kohri , Kazunori Nakayama

The flux of cosmic-ray high-energy positrons has recently been measured by AMS with unprecedented precision. This flux is well above the expectation from secondary positrons made by the observed fluxes of nuclear cosmic rays impinging on…

High Energy Physics - Phenomenology · Physics 2019-09-05 A. De Rújula

We carry out a detailed analysis of fluxes of cosmic ray antiprotons, positrons, electrons and photons to be expected from the annihilation of relic heavy neutrinos in the galactic halo. The spectra of particles are evaluated by Monte Carlo…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yu. A. Golubkov , R. V. Konoplich

In a recent paper (Moskalenko et al., 2002), it has been shown that the flux of secondary cosmic ray (CR) antiprotons appears to be contradictory to measurements of secondary to primary nuclei ratios in cosmic rays when calculated in the…

Astrophysics · Physics 2010-05-27 V. S. Ptuskin , I. V. Moskalenko , F. C. Jones , A. W. Strong , S. G. Mashnik

It is well established that phenomenological two-zone diffusion models of the galactic halo can very well reproduce cosmic-ray nuclear data and the observed antiproton flux. Here, we consider lepton propagation in such models and compute…

Astrophysics of Galaxies · Physics 2015-05-28 Torsten Bringmann , Fiorenza Donato , Roberto A. Lineros

We have made a calculation of the propagation of positrons from dark-matter particle annihilation in the Galactic halo in different models of the dark matter halo distribution using our 3D code, and present fits to our numerical propagation…

Astrophysics · Physics 2009-10-31 I. V. Moskalenko , A. W. Strong

Despite significant efforts over the past decade, the origin of the cosmic ray positron excess has still not been unambiguously established. A popular class of candidate sources are pulsars or pulsar wind nebulae but these cannot also…

High Energy Astrophysical Phenomena · Physics 2021-12-13 Philipp Mertsch , Andrea Vittino , Subir Sarkar

We show that the positron excess measured by the PAMELA experiment in the region between 10 and 100 GeV may well be a natural consequence of the standard scenario for the origin of Galactic cosmic rays. The 'excess' arises because of…

High Energy Astrophysical Phenomena · Physics 2009-09-02 Pasquale Blasi

The propagation of high-energy cosmic rays in the Galaxy is investigated. Solutions of a diffusion model are combined with numerically calculated trajectories of particles. The resulting escape path length and interaction path length are…

Astrophysics · Physics 2016-08-31 Joerg R. Hoerandel , Nikolai N. Kalmykov , Aleksei V. Timokhin

We use the constraints on the diffusion parameters as obtained with stable nuclei to calculate the cosmic antiproton flux from annihilating relic neutralinos. We discuss the relevance of each characteristic parameter, describing our two…

Astrophysics · Physics 2007-05-23 Fiorenza Donato , Nicolao Fornengo , David Maurin , Pierre Salati , Richard Taillet

Based on the Gluon Condensation (GC) model, the relationship between the spectra of electrons, $\gamma$ rays, and neutrinos in cosmic rays can be deduced. It has been found that these particles share the same parameter, $\beta_p$, and have…

High Energy Astrophysical Phenomena · Physics 2024-06-21 Jintao Wu , Jianhong Ruan

Measurements of the cosmic ray antiproton spectrum can be used to search for contributions from annihilating dark matter and to constrain the dark matter annihilation cross section. Depending on the assumptions made regarding cosmic ray…

High Energy Astrophysical Phenomena · Physics 2015-03-19 Dan Hooper , Tim Linden , Philipp Mertsch

Simulating the irradiation of planetary atmospheres by cosmic ray particles requires, among others, the ability to understand and to quantify the interactions of charged particles with planetary magnetic fields. Here we present a process…

Earth and Planetary Astrophysics · Physics 2022-03-14 Jason Hirtz , Ingo Leya

Cosmic ray antiprotons have been detected for over 20 years and are now measured reliably. Standard particle and astrophysics predict a conventional spectrum and abundance of secondary antiprotons consistent with all current measurements.…

Astrophysics · Physics 2016-11-03 Dallas C. Kennedy

High-energy collisions of cosmic-ray nuclei with interstellar gas are believed to be the mechanism producing the majority of cosmic ray antiprotons. Due to the kinematics of the process they are created with a nonzero momentum; the…

Astrophysics · Physics 2010-05-28 I. V. Moskalenko , A. W. Strong , J. F. Ormes , M. S. Potgieter

The rise in the cosmic-ray positron fraction measured by the PAMELA satellite is likely due to the presence of astrophysical sources of positrons, e.g. pulsars, on the kpc scale around the Earth. Nevertheless, assessing the properties of…

High Energy Astrophysical Phenomena · Physics 2011-07-19 Julien Lavalle

Measurements of the intensity of primary cosmic-ray protons reported in the last two years suggest a lower normalization than some earlier measurements. Here we comment on the measurements, compare them to assumptions made in two…

High Energy Physics - Phenomenology · Physics 2007-05-23 Thomas K. Gaisser