scholarly journals Cosmic ray transport and anisotropies to high energies

2015 ◽  
Vol 2 ◽  
pp. 39-44 ◽  
Author(s):  
P. L. Biermann ◽  
L. I. Caramete ◽  
A. Meli ◽  
B. N. Nath ◽  
E.-S. Seo ◽  
...  
Keyword(s):  
Cosmic Ray ◽  
High Energy ◽  
Wave Number ◽  
Ultra High Energy ◽  
Galactic Magnetic Field ◽  
Chemical Abundances ◽  
High Energy Cosmic Rays ◽  
High Energies ◽  
Isotropic Approximation ◽  
Galactic Cosmic Ray

Abstract. A model is introduced, in which the irregularity spectrum of the Galactic magnetic field beyond the dissipation length scale is first a Kolmogorov spectrum k-5/3 at small scales λ = 2 π/k with k the wave-number, then a saturation spectrum k-1, and finally a shock-dominated spectrum k-2 mostly in the halo/wind outside the Cosmic Ray disk. In an isotropic approximation such a model is consistent with the Interstellar Medium (ISM) data. With this model we discuss the Galactic Cosmic Ray (GCR) spectrum, as well as the extragalactic Ultra High Energy Cosmic Rays (UHECRs), their chemical abundances and anisotropies. UHECRs may include a proton component from many radio galaxies integrated over vast distances, visible already below 3 EeV.

scholarly journals Origins of Extragalactic Cosmic Ray Nuclei by Contracting Alignment Patterns induced in the Galactic Magnetic Field

2019 ◽  
Vol 210 ◽  
pp. 04004
Author(s):  
Martin Erdmann ◽  
Lukas Geiger ◽  
David Schmidt ◽  
Martin Urban ◽  
Marcus Wirtz
Keyword(s):  
Magnetic Field ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
High Energy ◽  
Ultra High Energy ◽  
Galactic Magnetic Field ◽  
High Energy Cosmic Rays ◽  
Novel Approach ◽  
Astrophysical Scenario ◽  
The Individual

We present a novel approach to search for origins of ultra-high energy cosmic rays. In a simultaneous fit to all observed cosmic rays we use the galactic magnetic field as a mass spectrometer and adapt the nuclear charges such that their extragalactic arrival directions are concentrated in as few directions as possible. During the fit the nuclear charges are constraint by the individual energy and shower depth measurements. We show in a simulated astrophysical scenario that source directions can be reconstructed even within a substantial isotropic background.

scholarly journals Covering the celestial sphere at ultra-high energies: Full-sky cosmic-ray maps beyond the ankle and the flux suppression

2019 ◽  
Vol 210 ◽  
pp. 01005 ◽  
Author(s):  
J. Biteau ◽  
T. Bister ◽  
L. Caccianiga ◽  
O. Deligny ◽  
A. di Matteo ◽  
...  
Keyword(s):  
Large Scale ◽  
Cosmic Ray ◽  
High Energy ◽  
Ultra High Energy ◽  
Telescope Array ◽  
High Energy Cosmic Rays ◽  
High Energies ◽  
The Past ◽  
Celestial Equator ◽  
Celestial Sphere

Despite deflections by Galactic and extragalactic magnetic fields, the distribution of ultra-high energy cosmic rays (UHECRs) over the celestial sphere remains a most promising observable for the identification of their sources. Thanks to a large number of detected events over the past years, a large-scale anisotropy at energies above 8 EeV has been identified, and there are also indications from the Telescope Array and Pierre Auger Collaborations of deviations from isotropy at intermediate angular scales (about 20 degrees) at the highest energies. In this contribution, we map the flux of UHECRs over the full sky at energies beyond each of two major features in the UHECR spectrum – the ankle and the flux suppression -, and we derive limits for anisotropy on different angular scales in the two energy regimes. In particular, full-sky coverage enables constraints on low-order multipole moments without assumptions about the strength of higher-order multipoles. Following previous efforts from the two Collaborations, we build full-sky maps accounting for the relative exposure of the arrays and differences in the energy normalizations. The procedure relies on cross-calibrating the UHECR fluxes reconstructed in the declination band around the celestial equator covered by both observatories. We present full-sky maps at energies above ~ 10 EeV and ~ 50 EeV, using the largest datasets shared across UHECR collaborations to date. We report on anisotropy searches exploiting full-sky coverage and discuss possible constraints on the distribution of UHECR sources.

scholarly journals High energy cosmic ray interactions and UHECR composition problem

2019 ◽  
Vol 210 ◽  
pp. 02001
Author(s):  
Sergey Ostapchenko
Keyword(s):  
Experimental Data ◽  
Monte Carlo ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
High Energy ◽  
Ultra High Energy ◽  
Hadronic Interactions ◽  
High Energy Cosmic Rays ◽  
Cosmic Ray Interactions ◽  
Composition Problem

The differences between contemporary Monte Carlo generators of high energy hadronic interactions are discussed and their impact on the interpretation of experimental data on ultra-high energy cosmic rays (UHECRs) is studied. Key directions for further model improvements are outlined. The prospect for a coherent interpretation of the data in terms of the UHECR composition is investigated.

scholarly journals Multimessenger observations of counterparts to IceCube-190331A

2020 ◽  
Vol 497 (3) ◽  
pp. 2553-2561
Author(s):  
Felicia Krauß ◽  
Emily Calamari ◽  
Azadeh Keivani ◽  
Alexis Coleiro ◽  
Phil A Evans ◽  
...  
Keyword(s):  
Spectral Energy Distribution ◽  
High Energy ◽  
Spectral Energy ◽  
Ultra High Energy ◽  
X Ray ◽  
High Energy Cosmic Rays ◽  
High Energies ◽  
Neutrino Event ◽  
Promising Tool ◽  
Localization Region

ABSTRACT High-energy neutrinos are a promising tool for identifying astrophysical sources of high and ultra-high energy cosmic rays (UHECRs). Prospects of detecting neutrinos at high energies (≳TeV) from blazars have been boosted after the recent association of IceCube-170922A and TXS 0506+056. We investigate the high-energy neutrino, IceCube-190331A, a high-energy starting event (HESE) with a high likelihood of being astrophysical in origin. We initiated a Swift/XRT and UVOT tiling mosaic of the neutrino localization and followed up with ATCA radio observations, compiling a multiwavelength spectral energy distribution (SED) for the most likely source of origin. NuSTAR observations of the neutrino location and a nearby X-ray source were also performed. We find two promising counterpart in the 90 per cent confidence localization region and identify the brightest as the most likely counterpart. However, no Fermi/LAT γ-ray source and no prompt Swift/BAT source is consistent with the neutrino event. At this point, it is unclear whether any of the counterparts produced IceCube-190331A. We note that the Helix Nebula is also consistent with the position of the neutrino event and we calculate that associated particle acceleration processes cannot produce the required energies to generate a high-energy HESE neutrino.

scholarly journals Methods to measure the cosmic-ray composition with the Auger Engineering Radio Array

2019 ◽  
Vol 216 ◽  
pp. 02004 ◽  
Author(s):  
Fabrizia Canfora
Keyword(s):  
Cosmic Ray ◽  
High Energy ◽  
Mass Composition ◽  
Atmospheric Depth ◽  
Ultra High Energy ◽  
Air Showers ◽  
Radio Stations ◽  
High Energy Cosmic Rays ◽  
Air Shower ◽  
Number Of Particles

The mass composition of ultra-high-energy cosmic rays plays a key role in the understanding of the origins ofthese rare particles. A composition-sensitive observable is the atmospheric depth at which the air shower reaches the maximum number of particles (Xmax). The Auger Engineering Radio Array (AERA) detects the radio emission inthe 30-80 MHz frequency band from extensive air showers with energies larger than 1017 eV. It consists of more than 150 autonomous radio stations covering an area of about 17 km2. From the distribution of signals measured by the antennas, it is possible to estimate Xmax. In this contribution three independent methods for the estimation of Xmax will be presented.

scholarly journals COLOR GLASS CONDENSATE IN BRANE MODELS OR DON'T ULTRA HIGH ENERGY COSMIC RAYS PROBE 1015eV SCALE?

2005 ◽  
Vol 20 (06) ◽  
pp. 419-440 ◽  
Author(s):  
HOURI ZIAEEPOUR
Keyword(s):  
Cosmic Rays ◽  
Extra Dimension ◽  
Cosmic Ray ◽  
High Energy ◽  
Effective Density ◽  
Color Glass ◽  
Color Glass Condensate ◽  
Ultra High Energy ◽  
High Energy Cosmic Rays ◽  
Brane Models

In a previous work1 we have studied the propagation of relativistic particles in the bulk for some of the most popular brane models. Constraints have been put on the parameter space of these models by calculating the time delay due to propagation in the bulk of particles created during the interaction of Ultra High Energy Cosmic Rays (UHECRs) with protons in the terrestrial atmosphere. The question was, however, raised that probability of hard processes in which bulk modes can be produced is small and consequently, the tiny flux of UHECRs cannot constrain brane models. Here we use Color Glass Condensate (CGC) model to show that effects of extra dimensions are visible not only in hard processes when the incoming photon/parton hits a massive Kaluza–Klein mode but also through the modification of soft/semi-hard parton distribution. At classical level, for an observer in the CM frame of UHECR and atmospheric hadrons, color charge sources are contracted to a thin sheet with a width inversely proportional to the energy of the ultra energetic cosmic ray hadron and consequently they can see an extra dimension with comparable size. Due to QCD interaction, a short life swarm of partons is produced in front of the sheet and its partons can penetrate to the extra-dimension bulk. This reduces the effective density of partons on the brane or in a classical view creates a delay in the arrival of the most energetic particles if they are reflected back due to the warping of the bulk. In CGC approximation the density of swarm at different distances from the classical sheet can be related and therefore it is possible (at least formally) to determine the relative fraction of partons in the bulk and on the brane at different scales. Results of this work are also relevant to the test of brane models in hadron colliders like LHC.

Black holes and high energy physics

2016 ◽  
Vol 31 (02n03) ◽  
pp. 1641016
Author(s):  
A. A. Grib ◽  
Yu. V. Pavlov
Keyword(s):  
Black Holes ◽  
High Energy Physics ◽  
High Energy ◽  
Ultra High Energy ◽  
Particle Collisions ◽  
High Energy Cosmic Rays ◽  
High Energies ◽  
The Earth ◽  
Superheavy Dark Matter ◽  
Energy Physics

Three mechanisms of getting high energies in particle collisions in the ergosphere of the rotating black holes are considered. The consequences of these mechanisms for observation of ultra high energy cosmic rays particles on the Earth as result of conversion of superheavy dark matter particles into ordinary particles are discussed.

scholarly journals Propagation of Ultra-high-energy Cosmic Rays in Galactic Magnetic Field

2011 ◽  
Author(s):  
Hajime Takami ◽  
Hiroyuki Sagawa ◽  
Yoshiya Kawasaki ◽  
Takashi Sako ◽  
Masahiro Takeda ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Cosmic Rays ◽  
High Energy ◽  
Ultra High Energy ◽  
Galactic Magnetic Field ◽  
High Energy Cosmic Rays

scholarly journals CODALEMA: A COSMIC RAY AIR SHOWER RADIO DETECTION EXPERIMENT

2006 ◽  
Vol 21 (supp01) ◽  
pp. 192-196 ◽  
Author(s):  
D. ARDOUIN ◽  
A. BELLETOILE ◽  
D. CHARRIER ◽  
R. DALLIER ◽  
L. DENIS ◽  
...  
Keyword(s):  
Cosmic Rays ◽  
Cosmic Ray ◽  
High Energy ◽  
Ultra High Energy ◽  
Air Showers ◽  
Detection Experiment ◽  
Transient Signals ◽  
High Energy Cosmic Rays ◽  
Air Shower ◽  
Radio Detection

The CODALEMA experimental device currently detects and characterizes the radio contribution of cosmic ray air showers : arrival directions and electric field topologies of radio transient signals associated to cosmic rays are extracted from the antenna signals. The measured rate, about 1 event per day, corresponds to an energy threshold around 5.1016eV. These results allow to determine the perspectives offered by the present experimental design for radiodetection of Ultra High Energy Cosmic Rays at a larger scale.

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