Results 51 to 60 of about 2,282,970 (386)
Improved constraints on cosmic birefringence from the WMAP and Planck cosmic microwave background polarization data [PDF]
Physical Review D, 2022 The observed pattern of linear polarization of the cosmic microwave background (CMB) photons is a sensitive probe of physics violating parity symmetry under inversion of spatial coordinates. A new parity-violating interaction might have rotated the plane
J. R. Eskilt, E. Komatsu
semanticscholar +1 more source
The origin of galactic cosmic rays [PDF]
, 2007 The origin of galactic cosmic rays is one of the most interesting unsolved problems in astroparticle physics. Experimentally, the problem is attacked by a multi-disciplinary effort, namely by direct measurements of cosmic rays above the atmosphere, by ...
Aharonian +54 more
core +3 more sources
Nuclear Physics Meets the Sources of the Ultra-High Energy Cosmic Rays [PDF]
Scientific Reports, 2016 The determination of the injection composition of cosmic ray nuclei within astrophysical sources requires sufficiently accurate descriptions of the source physics and the propagation – apart from controlling astrophysical uncertainties.
D. Boncioli, A. Fedynitch, W. Winter
semanticscholar +1 more source
Overview of the Auger@TA project and preliminary results from Phase I [PDF]
EPJ Web of Conferences, 2019 We report on the first results of a unique in-situ experimental cross-calibration effort of the surface detector of the Pierre Auger Observatory and of the Telescope Array experiment (Auger@TA).
Sarazin Fred +12 more
doaj +1 more source
Cosmic Strings and Cosmic Superstrings [PDF]
Nucl.Phys.Proc.Suppl.192-193:68-90,2009, 2009 In these lectures, I review the current status of cosmic strings and cosmic superstrings. I first discuss topological defects in the context of Grand Unified Theories, focusing in particular in cosmic strings arising as gauge theory solitons. I discuss the reconciliation between cosmic strings and cosmological inflation, I review cosmic string dynamics,
arxiv +1 more source
The Auger@TA Project: Phase II Progress and Plans [PDF]
EPJ Web of Conferences, 2019 The Auger@TA project is a combined effort involving members of both the Pierre Auger Observatory and the Telescope Array experiment (TA) to cross-calibrate detectors and compare results on air showers detected at one location.
Covault Corbin +12 more
doaj +1 more source
On the physical basis of cosmic time [PDF]
Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics, 2009 44 pages.
Henrik Zinkernagel, Svend E. Rugh
openaire +4 more sources
The “SPectrogram Analysis and Cataloguing Environment” (SPACE) labelling tool
Frontiers in Astronomy and Space Sciences, 2022 The SPectrogram Analysis and Cataloguing Environment (SPACE) tool is an interactive python tool designed to label radio emission features of interest in a time-frequency map (called “dynamic spectrum”).
Corentin Louis +9 more
doaj +1 more source
Hubble Tension: The Evidence of New Physics [PDF]
Universe, 2023 The ΛCDM model provides a good fit to most astronomical observations but harbors large areas of phenomenology and ignorance. With the improvements in the precision and number of observations, discrepancies between key cosmological parameters of this ...
Jian-Ping Hu, Fayin Wang
semanticscholar +1 more source
The Impact of Cosmic Ray Injection on Magnetic Flux Tubes in a Galactic Disk [PDF]
, 2022 In galactic disks, the Parker instability results when non-thermal pressure support exceeds a certain threshold. The non-thermal pressures considered in the Parker instability are cosmic ray pressure and magnetic pressure. This instability takes a long time to saturate $(>500 \, \mathrm{Myr})$ and assumes a background with fixed cosmic ray pressure to ...
arxiv +1 more source