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

Cosmic Rays and Neutrinos from Gamma Ray Bursts

We review the hypothesis that the acceleration of protons at internal shocks in Gamma Ray Bursts (GRB) could be the origin of the ultra-high energy cosmic rays (UHECR) observed at earth, E_max > 10^19 eV. We find that, even though protons may be accelerated to such energies, their ejection into the interstellar/intergalactic medium is problematic because it is likely to be accompanied by considerable adiabatic losses in the expanding shell. The problem is circumvented by neutrons produced in photohadronic interactions, which are not magnetically bound and thus effectively ejected in the moment of their production. They can be both produced in sufficient number and be able to leave the emission region if the optical depth of the emission region to photohadronic interactions is of order 1. We show that this requirement can be fulfilled under the same conditions which allow acceleration of protons to the highest energies. The production of neutrinos in this process correlates the fluxes of cosmic rays and neutrinos, and makes the hypothesis of UHECR origin in GRBs testable.Comment: LaTeX, 5 pages, 1 figure embedded using epsf.sty. Paper presented at the 4th Huntsville Symposium on GRB, 1997. Compared to published version, minor typo in Eq. (3) corrected and references update

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

On photohadronic processes in astrophysical environments

We discuss the first applications of our newly developed Monte Carlo event generator SOPHIA to multiparticle photoproduction of relativistic protons with thermal and power law radiation fields. The measured total cross section is reproduced in terms of excitation and decay of baryon resonances, direct pion production, diffractive scattering, and non-diffractive multiparticle production. Non--diffractive multiparticle production is described using a string fragmentation model. We demonstrate that the widely used `$\Delta$--approximation' for the photoproduction cross section is reasonable only for a restricted set of astrophysical applications. The relevance of this result for cosmic ray propagation through the microwave background and hadronic models of active galactic nuclei and gamma-ray bursts is briefly discussed.Comment: 9 pages including 4 embedded figures, submitted to PAS

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

Historia y definición de conceptos sobre trasplante, donación y tráfico de órganos

En todo el mundo se ha venido generando la cultura de la donación de órganos con el fin de salvaguardar la vida, teniendo en cuenta la técnica del trasplante de tejidos u órganos afines donde el cuerpo queda igual, sin desfigurarse, este tratamiento depende únicamente de la relación genética entre el donador y el receptor , en la actualidad los avances de la medicina hacen posible que los órganos lesionados puedan recuperarsen totalmente, por lo que hace que el número de personas que viven gracias al trasplante sea cada día mayor, de esta realidad afortunada para el mejoramiento y conservación de la vida humana, se genera una gran inquietud, que es la problemática suscitada con la oferta y la demanda de los órganos a trasplantar, puesto que la poca oferta ha hecho que la comunidad busque una salida, denominada Tráfico de Órganos que es la venta a título oneroso de una parte corporal, venta de órganos en vida o extracción ocurrida después de la muerte, es de suma importancia resaltar que el tráfico de órganos es un problema a nivel universal por la carencia de órganos para salvar vidas