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arXiv · 1004.1413

Discovery of a GeV blazar shining through the Galactic plane

J. Vandenbroucke·R. Buehler·M. Ajello·K. Bechtol·A. Bellini·M. Bolte·C. C. Cheung·F. Civano·D. Donato·L. Fuhrmann·S. Funk·S. E. Healey·A. B. Hill·C. Knigge·G. M. Madejski·R. W. Romani·M. Santander-García·M. S. Shaw·D. Steeghs·M. A. P. Torres·A. Van Etten·K. A. Williams
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Abstract

The \emph{Fermi} Large Area Telescope (LAT) discovered a new gamma-ray source near the Galactic plane, \object{Fermi J0109+6134}, when it flared brightly in 2010 February. The low Galactic latitude (b =-1.2\degr) indicated that the source could be located within the Galaxy, which motivated rapid multi-wavelength follow-up including radio, optical, and X-ray observations. We report the results of analyzing all 19 months of LAT data for the source, and of X-ray observations with both \emph{Swift} and the \emph{Chandra X-ray Observatory}. We determined the source redshift, z =0.783, using a Keck LRIS observation. Finally, we compiled a broadband spectral energy distribution (SED) from both historical and new observations contemporaneous with the 2010 February flare. The redshift, SED, optical line width, X-ray absorption, and multi-band variability indicate that this new GeV source is a blazar seen through the Galactic plane. Because several of the optical emission lines have equivalent width >5Å, this blazar belongs in the flat-spectrum radio quasar category.

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J. Vandenbroucke, R. Buehler, M. Ajello, K. Bechtol, A. Bellini, M. Bolte, C. C. Cheung, F. Civano, D. Donato, L. Fuhrmann, S. Funk, S. E. Healey, A. B. Hill, C. Knigge, G. M. Madejski, R. W. Romani, M. Santander-García, M. S. Shaw, D. Steeghs, M. A. P. Torres, A. Van Etten, K. A. Williams. 2010-04-08. Discovery of a GeV blazar shining through the Galactic plane. https://doi.org/10.1088/2041-8205%2F718%2F2%2Fl166

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