▪ Abstract A large collective effort to study the variability of active galactic nuclei (AGN) over
the past decade has led to a number of fundamental results on radio-quiet AGN and blazars …

We demonstrate the importance of near-infrared radiation from hot dust for Compton cooling
of electrons/positrons in quasar jets. In our model, we assume that the nonthermal radiation …

A long-standing question in extragalactic astrophysics is the composition of the relativistic
jets of plasma that stream from the nuclei of quasars and active galaxies—do they consist of …

The central engine causing the production of jets in radio sources may work intermittently,
accelerating shells of plasma with different mass, energy and velocity. Faster but later shells …

We obtain the maximum diffuse neutrino intensity predicted by hadronic photoproduction
models of the type which have been applied to the jets of active galactic nuclei or gamma …

We treat the production of neutrons, photons, and neutrinos through photomeson
interactions of relativistic protons with ambient photons in the compact inner jets of blazars …

We elucidate the physical basis for the upper bound on high energy neutrino fluxes implied
by the observed cosmic ray flux. We stress that the bound is valid for neutrinos produced …

We present multiwavelength data for 12 blazars observed from 2008 to 2010 as part of an
ongoing optical–infrared photometric monitoring project. Sources were selected to be bright …

An important radiation field for photomeson neutrino production in blazars is shown to be the
radiation field external to the jet. Assuming that protons are accelerated with the same power …

We report the results of a multiband observing campaign on the famous blazar 3C 279
conducted during a phase of increased activity from 2013 December to 2014 April, including …