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arXiv · 0905.0843

On the identification of the Fermi/LAT source 0FGL J2001.0+4352 with a BL Lac

L. Bassani·R. Landi·N. Masetti·P. Parisi·A. Bazzano·P. Ubertini
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Abstract

We report on the identification of the gamma-ray source 0FGL J20001.0+4352 listed in the Fermi bright source catalogue. This object, which has an observed 1-100 GeV flux of (7.8 +/- 1.2) x 10^{-9} ph cm^{-2} s^{-1} and is located close to the Galactic plane, is not associated with any previously known high energy source. We use archival XMM-Newton and Swift/XRT data to localise with arcsec accuracy the X-ray counterpart of this GeV emitter and to characterise its X-ray properties: the source is bright (the 0.2-12 keV flux is 1.9 x 10^{-12} erg cm^{-2} s^{-1}), variable (by a factor of ~2) and with a steep power law spectrum (Gamma = 2.7). It coincides with a radio bright (~200 mJy at 8.4 GHz) and flat spectrum object (MG4 J200112+4352 in NED). Broad-band optical photometry of this source suggests variability also in this waveband, while a spectroscopic follow-up observation provides the first source classification as a BL Lac object. The source SED, as well as the overall characteristics and optical classification, point to a high frequency peaked blazar identification for 0FGL J2001.0+4352.

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L. Bassani, R. Landi, N. Masetti, P. Parisi, A. Bazzano, P. Ubertini. 2009-05-06. On the identification of the Fermi/LAT source 0FGL J2001.0+4352 with a BL Lac. https://doi.org/10.1111/j.1745-3933.2009.00683.x

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