Related papers: Constraints on Large-Scale Magnetic Fields from th…
Strange quark matter could be found in the core of neutron stars or forming strange quark stars. As is well known, these astrophysical objects are endowed with strong magnetic fields which affect the microscopic properties of matter and…
We wish to clarify whether strong magnetic fields can be effectively generated in typically low-mass dwarf galaxies and to assess the role of dwarf galaxies in the magnetization of the Universe. We performed a search for radio emission and…
We search for signals of magnetically-induced effects in the arrival directions of ultra-high-energy cosmic rays detected at the Pierre Auger Observatory. We apply two different methods. One is a search for sets of events that show a…
The Galactic magnetic field is important in the dynamics of our Galaxy. It is believed to play a role in star formation and influence the structure of the Galaxy. In order to understand how the Galactic magnetic field originally formed or…
Magnetic fields are amplified as a consequence of galaxy formation and turbulence-driven dynamos. Galaxy mergers can potentially amplify the magnetic fields from their progenitors, making the magnetic fields dynamically important. However,…
The Pierre Auger Collaboration has provided a compelling indication for a possible correlation between the arrival directions of ultrahigh-energy cosmic rays and nearby starburst galaxies. Herein we show how the latest large-scale modeling…
It is argued that if extragalactic magnetic fields are smaller than 2x10^{-12} G the flux of ultra-high energy photons of (a few)x10^{-1} eV cm^{-2}s^{-1}sr^{-1} predicted in the top-down models of UHE CR implies similar flux of the diffuse…
Recent results obtained with the Pierre Auger Observatory are described. These include measurements of the spectrum, anisotropies and composition of ultra-high energy cosmic rays. The ankle of the spectrum is measured at $4\times…
I review what is known and surmised about magnetic fields in space, from our Milky Way environment to the distant Universe beyond the GZK horizon. This includes our gradually improving specification of the CR propagation environment within…
Very high energy photons from cosmological gamma-ray bursts (GRBs) are expected to interact with extragalactic background light (EBL) and produce electron-positron pairs when they propagate through intergalactic medium (IGM). These…
Magnetic fields are observed everywhere in the universe. In this review, we concentrate on the observational aspects of the magnetic fields of Galactic and extragalactic objects. Readers can follow the milestones in the observations of…
A thorough search for large scale anisotropies in the distribution of arrival directions of cosmic rays detected above $10^{18}$ eV at the Pierre Auger Observatory is presented. This search is performed as a function of both declination and…
Distant BL Lacertae objects emit $\gamma$ rays which interact with the extragalactic background light (EBL), creating electron-positron pairs, and reducing the flux measured by ground-based imaging atmospheric Cherenkov telescopes (IACTs)…
Several analyses of the data collected by other experiments have found an excess of cosmic rays in correlation with subclasses of BL Lacs. Data from the Pierre Auger Observatory do not support previously reported excesses. The number of…
The energy content of large-scale jets in FR I radio galaxies is still an open issue. Here we show that upper limits on the high-energy and very high-energy gamma-ray emission of the kpc-scale jet in M 87 radio galaxy imposed by EGRET,…
We discuss the effects of diffusion of high energy cosmic rays in turbulent extra-galactic magnetic fields. We find an approximate expression for the low energy suppression of the spectrum of the different mass components (with charge $Z$)…
The observation of cosmic ray particles with unexpected high energies is pushing astroparticle physics into a period of rapid progress both theoretically and experimentally. Different proposed models for the generation of these particles…
We express the mean square deflections of the ultra-high energy cosmic rays (UHECR) caused by the random component of the Galactic magnetic field (GMF) in terms of the GMF power spectrum. We use recent measurements of the GMF spectra in…
We introduce a method to constrain the characteristic angular size of the brightest cosmic-ray sources observed above 57 \times 1018 eV. By angular size of a source, we mean the effective angular extent over which cosmic-rays from that…
Most models of the origin of ultra high energy cosmic rays rely on the existence of luminous extragalactic sources. Cosmic rays escaping the galaxy where the source is located produce a sufficiently large electric current to justify the…