标题： 关于Fermi/LAT源0FGL J2001.0+4352与BL Lac的识别 显示英文标题

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

摘要： 我们报告了费米亮源目录中列出的伽马射线源 0FGL J20001.0+4352 的识别结果。 该天体具有观测到的 1-100 GeV 流量 (7.8 ± 1.2) × 10^{-9} 光子 cm^{-2} s^{-1}，并且位于银河平面附近，与任何已知的高能源均无关联。 我们使用存档的 XMM-Newton 和 Swift/XRT 数据以角秒精度定位了此 GeV 发射器的 X 射线对应体，并对其 X 射线特性进行了表征：该源明亮（0.2-12 keV 流量为 1.9 × 10^{-12} erg cm^{-2} s^{-1}），可变性（变化因子约为 2）且具有陡峭的幂律谱（Γ = 2.7）。 它与一个射电明亮（在 8.4 GHz 处约 200 mJy）且具有平坦光谱的天体一致（NED 中的 MG4 J200112+4352）。 对该源的宽波段光学测光表明此波段也存在变化，而光谱后续观测提供了首个源分类为 BL Lac 对象。 源的 SED 以及整体特性和光学分类表明 0FGL J2001.0+4352 是一个高频峰耀变星。 显示英文摘要

摘要： 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.