Multiwavelength Observations of Strong Flares from the TeV Blazar 1ES 1959+650

• Published in: The Astrophysical journal 2004-01, Vol.601 (1), p.151-164
• Main Authors: Krawczynski, H, Hughes, S. B, Horan, D, Aharonian, F, Aller, M. F, Aller, H, Boltwood, P, Buckley, J, Coppi, P, Fossati, G, Götting, N, Holder, J, Horns, D, Kurtanidze, O. M, Marscher, A. P, Nikolashvili, M, Remillard, R. A, Sadun, A, Schröder, M
• Format: Article
• Language: English
• Subjects: Active and peculiar galaxies (including bl lacertae objects, blazars, seyfert galaxies, markarian galaxies, active galactic nuclei); Astronomy; Earth, ocean, space; Exact sciences and technology; Quasars. Active or peculiar galaxies, objects, and systems; Stellar systems. Galactic and extragalactic objects and systems. The universe
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1086/380393

Following the detection of strong TeV gamma-ray flares from the BL Lac object 1ES 1959+650 with the Whipple 10 m Cerenkov telescope on 2002 May 16 and 17, we performed intensive target of opportunity radio, optical, X-ray, and TeV gamma-ray observations from 2002 May 18 to August 14. Observations with the X- ray telescope Rossi X-Ray Timing Explorer and the Whipple and HEGRA gamma- ray telescopes revealed several strong flares, enabling us to sensitively test the X-ray-gamma-ray flux correlation properties. Although the X-ray and gamma- ray fluxes seemed to be correlated in general, we found an "orphan" gamma-ray flare that was not accompanied by an X-ray flare. While we detected optical flux variability with the Boltwood and Abastumani observatories, the data did not give evidence for a correlation of the optical flux variability with the observed X-ray and gamma-ray flares. Within statistical errors of about 0.03 Jy at 14.5 GHz and 0.05 Jy at 4.8 GHz, the radio fluxes measured with the University of Michigan Radio Astronomy Observatory stayed constant throughout the campaign; the mean values agreed well with the values measured on 2002 May 7 and June 7 at 4.9 and 15 GHz with the Very Large Array and at 4.8 GHz with archival flux measurements. After describing in detail the radio, optical, X-ray and gamma-ray light curves, and spectral energy distributions (SEDs), we present initial modeling of the SED with a simple synchrotron self-Compton model. With the addition of another TeV blazar with good broadband data, we consider the set of all TeV blazars, to begin to look for a connection of the jet properties to the properties of the central accreting black hole thought to drive the jet. Remarkably, the temporal and spectral X-ray and gamma-ray emission characteristics of TeV blazars are very similar, even though the mass estimates of their central black holes differ by up to 1 order of magnitude.