685 research outputs found
Hadronic blazar models and correlated X-ray/TeV flares
The hypothesis that AGN jets might be the sources of the ultra-high energy
cosmic rays has originally motivated the venture of TeV gamma ray astronomy.
Surprisingly, after the discovery of TeV emission from blazars the attention
has shifted to more traditional explanations which do not involve energetic
hadrons, and there is even common believe that a hadronic interpretation is
disfavored by observations. It is shown here that this is not the case, and
that the currently observed spectra and variability features of blazars can be
perfectly understood within hadronic blazar models. I also discuss how hadronic
models might be observationally distinguished from common leptonic models, and
point out some interesting aspects which could be relevant for the
understanding of the differences between blazar classes.Comment: 12 pages LaTeX (aipproc), 3 eps figures included. Invited review
presented at the workshop "GeV-TeV Gamma-Ray Astrophysics", Snowbird, Utah,
199
Conspiratorial cosmology - the case against the Universe
Based on the cosmological results of the Planck Mission, we show that all
parameters describing our Universe within the \Lambda CDM model can be
constructed from a small set of numbers known from conspiracy theory. Our
finding is confirmed by recent data from high energy particle physics. This
clearly demonstrates that our Universe is a plot initiated by an unknown
interest group or lodge. We analyse possible scenarios for this conspiracy, and
conclude that the belief in the existence of our Universe is an illusion, as
previously assumed by ancient philosophers, 20th century science fiction
authors and contemporary film makers.Comment: 4 page
Prompt high-energy neutrinos from gamma-ray bursts in photospheric and synchrotron self-Compton scenarios
We investigate neutrino emission from gamma-ray bursts (GRBs) under
alternative scenarios for prompt emission (the photospheric and synchrotron
self-Compton scenarios) rather than the classical optically thin synchrotron
scenario. In the former scenario, we find that neutrinos from the pp reaction
can be very important at energies around 10-100 TeV. They may be detected by
IceCube/KM3Net and useful as a probe of baryon acceleration around/below the
photosphere. In the latter scenario, we may expect about EeV pgamma neutrinos
produced by soft photons. Predicted spectra are different from that in the
classical scenario, and neutrinos would be useful as one of the clues to the
nature of GRBs (the jet composition, emission radius, magnetic field and so
on).Comment: 5 pages, 3 figures, replaced to match the final version published as
PRD Rapid Communication, 78, 101302. Minor typos fixe
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