Variability and Spectral Characteristics of Three Flaring Gamma-Ray Quasars Observed by VERITAS and Fermi-LAT

Flat spectrum radio quasars (FSRQs) are the most luminous blazars at GeV energies, but only rarely emit detectable fluxes of TeV gamma rays, typically during bright flares. We explore gamma-ray variability and spectral characteristics three FSRQs that have been observed energies by Fermi-LAT VERITAS, making use almost 100 hours VERITAS observations spread over 10 years: 3C 279, PKS 1222+216, Ton 599. explain flux distributions sources in terms a model derived from stochastic differential equation describing fluctuations magnetic field accretion disk, estimate timescales accumulation instabilities their disks. identify distinct flares using procedure based on Bayesian blocks analyze daily sub-daily energy spectra. Using as well Fermi, Swift, Steward Observatory, we broadband 1222+216 599 VHE-detected 2014 2017, respectively, strongly constraining jet Doppler factors emission region locations these events. Finally, place theoretical constraints potential production PeV-scale neutrinos VHE