arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0705.0887astro-ph
收藏

BL Lacertae天体大样本的37 GHz观测

37 GHz observations of a large sample of BL Lacertae objects

E. Nieppola, M. Tornikoski, A. Lähteenmäki, E. Valtaoja, T. Hakala, T. Hovatta, M. Kotiranta, S. Nummila, T. Ojala, M. Parviainen, M. Ranta, P. -M. Saloranta, I… 展开作者

E. Nieppola, M. Tornikoski, A. Lähteenmäki, E. Valtaoja, T. Hakala, T. Hovatta, M. Kotiranta, S. Nummila, T. Ojala, M. Parviainen, M. Ranta, P. -M. Saloranta, I. Torniainen, M. Tröller

摘要:

我们提出了37 GHz的数据在Metsahovi射电天文台在2001年12月至2005年4月的BL Lacertae对象的大样本。我们还报告了在5 - 37 GHz和37 - 90 GHz频率间隔的平均变率指数和射电频谱指数。大约34%的样本在37 GHz被检测到,总共有136个BL Lacertae天体。绝大多数检测到的来源是低能量BL Lac(LBL)。样本的变异性指数值是多样的,样本的平均分数变异性为Δ S_2 = 0.31。频谱指数也有很大的变化,但样本源的平均无线电频谱是平坦的。我们的观测表明,许多通常被认为是无线电安静的高能BL Lac(HBL)有时可以在37 GHz处被检测到。

英文摘要:

We present 37 GHz data obtained at Metsahovi Radio Observatory in 2001 December - 2005 April for a large sample of BL Lacertae objects. We also report the mean variability indices and radio spectral indices in frequency intervals 5 - 37 GHz and 37 - 90 GHz. Approximately 34 % of the sample was detected at 37 GHz, 136 BL Lacertae objects in all. A large majority of the detected sources were low-energy BL Lacs (LBLs). The variability index values of the sample were diverse, the mean fractional variability of the sample being ΔS_2 = 0.31. The spectral indices also varied widely, but the average radio spectrum of the sample sources is flat. Our observations show that many of the high-energy BL Lacs (HBL), which are usually considered radio-quiet, can at times be detected at 37 GHz.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑