activity
20082013
collaborators

7 papers

astro-ph.HE2013

The awakening of BL Lacertae: observations by Fermi, Swift, and the GASP-WEBT

C. M. Raiteri, M. Villata, F. D'Ammando +4

Since the launch of the Fermi satellite, BL Lacertae has been moderately active at gamma-rays and optical frequencies until May 2011, when the source started a series of strong fla…

astro-ph.HE2013

A Tight Connection between Gamma-Ray Outbursts and Parsec-Scale Jet Activity in the Quasar 3C 454.3

Svetlana G. Jorstad, Alan P. Marscher, Paul S. Smith +42

We analyze the multifrequency behavior of the quasar 3C 454.3 during three prominent γ-ray outbursts: 2009 Autumn, 2010 Spring, and 2010 Autumn. The data reveal a repeating pattern…

astro-ph.HE2012

Variability of the blazar 4C 38.41 (B3 1633+382) from GHz frequencies to GeV energies

C. M. Raiteri, M. Villata, P. S. Smith +74

The quasar-type blazar 4C 38.41 (B3 1633+382) experienced a large outburst in 2011, which was detected throughout the entire electromagnetic spectrum. We present the results of low…

astro-ph.CO2011

The long-lasting activity of 3C 454.3. GASP-WEBT and satellite observations in 2008-2010

C. M. Raiteri, M. Villata, M. F. Aller +6

We present multiwavelength observations of 3C 454.3 from April 2008 to March 2010. The radio to optical data are mostly from the GASP-WEBT, UV and X-ray data from Swift, and gamma-…

astro-ph.CO2010

Another look at the BL Lacertae flux and spectral variability

C. M. Raiteri, M. Villata, L. Bruschini +52

The GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT) monitored BL Lacertae in 2008-2009 at radio, near-IR, and optical frequencies. During this period,…

astro-ph.CO2009

The June 2008 flare of Markarian 421 from optical to TeV energies

R. M. Wagner, I. Donnarumma, J. Grube +6

We present optical to very-high energy (VHE) gamma-ray observations of Mrk 421 between 2008 May 24 and June 23. A high-energy (HE) gamma-ray signal was detected by AGILE-GRID durin…