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We investigate two recent parameterizations of the galactic magnetic field with respect to their impact on cosmic nuclei traversing the field. We present a comprehensive study of the size of angular deflections, dispersion in the arrival probability distributions, multiplicity in the images of arrival on Earth, variance in field transparency, and influence of the turbulent field components. To remain restricted to ballistic deflections, a cosmic nucleus with energy E and charge Z should have a rigidity above E/Z=6 EV. In view of the differences resulting from the two field parameterizations as a measure of current knowledge in the galactic field, this rigidity threshold may have to be increased. For a point source search with E/Z>60 EV, field uncertainties increase the required signal events for discovery moderately for sources in the northern and southern regions, but substantially for sources near the galactic disk.
The observation of electromagnetic radiation from radio to $gamma$-ray wavelengths has provided a wealth of information about the universe. However, at PeV (10$^{15}$ eV) energies and above, most of the universe is impenetrable to photons. New messen
The investigation of the emergence of life is a major endeavour of science. Astronomy is contributing to it in three fundamental manners: (1) by measuring the chemical enrichment of the Universe, (2) by investigating planet formation and searching fo
We present the localization and host galaxies of one repeating and two apparently non-repeating Fast Radio Bursts. FRB20180301A was detected and localized with the Karl G. Jansky Very Large Array to a star-forming galaxy at $z=0.3304$. FRB20191228A,
Indirect constraints on the intensity of the Extragalactic Background Light (EBL) were provided by recent studies of extragalactic sources emitting sub-TeV to multi-TeV photons. These constraints are provided thanks to the absorption of gamma rays by
We present the first results from the new Survey of Extragalactic Nuclear Spectral Energies (SENSE) sample of blazars. The sample has been chosen with minimal selection effects and is therefore ideal to probe the intrinsic properties of the blazar po