The gamma-ray brightest days of the blazar 3C 454.3

TL;DR

This study analyzes the December 2009 gamma-ray flare of blazar 3C 454.3, revealing correlated multi-wavelength fluxes, a quadratic flux relationship, and jet power exceeding accretion luminosity, modeled with a simple synchrotron inverse Compton framework.

Contribution

It provides the first simultaneous multi-wavelength spectral energy distributions during a major flare and demonstrates the jet power surpasses accretion power, with a simple model explaining the flux correlations.

Findings

Optical, X-ray, and gamma-ray fluxes are correlated.

Gamma-ray flux varies quadratically with optical flux.

Jet power during the flare exceeds accretion disk luminosity.

Abstract

In the first week of December 2009, the blazar 3C 454.3 became the brightest high energy source in the sky. Its photon flux reached and surpassed the level of 1e-5 ph/cm2/s above 100 MeV. The Swift satellite observed the source several times during the period of high gamma-ray flux, and we can construct really simultaneous spectral energy distributions (SED) before, during, and after the luminosity peak. Our main findings are: i) the optical, X-ray and gamma-ray fluxes correlate; ii) the gamma-ray flux varies quadratically (or even more) with the optical flux; iii) a simple one-zone synchrotron inverse Compton model can account for all the considered SED; iv) in this framework the gamma-ray vs optical flux correlation can be explained if the magnetic field is slightly fainter when the overall jet luminosity is stronger; v) the power that the jet spent to produce the peak gamma-ray luminosity is of the same order, or larger, than the accretion disk luminosity. During the flare, the total jet power surely surpassed the accretion power.