Understanding Blazar Jets - The OVRO 40-m Blazar Monitoring Program

该项目的中心是使用欧文斯山谷射电天文台(OVRO，美国加利福尼亚州)的40米望远镜对1500颗Blaazar进行无线电监测，然后利用费米伽马射线数据进行联合分析。Blazar的动力来自于旋转的超大质量黑洞的吸积，这些黑洞沿着自旋轴产生相对论喷流，尽管这一过程的详细机制仍然不清楚。Blazar中的喷流与视线成小角度排列，结果是相对论光束显著增加了表观光度和可变性。费米伽马射线太空望远镜为我们提供了一种提高对喷流产生的理解的途径，该望远镜连续监测所有伽马射线明亮的耀斑，为系统研究Blazar喷流提供了前所未有的机会。伽马射线发射区的确切位置及其与中央黑洞的接近仍然是争论的主题，关于GeV发射区的两种主要相互竞争的模型。测试这些模型需要一种多波长方法，将费米观测与来自OVRO-40M的辅助射电观测相结合，以搜索不同频率下的光曲线中的相关性。

The project is centred round the radio monitoring of 1500 Blazars with the 40-m telescope at the Owens Valley Radio Observatory (OVRO, California, USA) and then producing a joint analysis with Fermi gamma ray data. Blazars are powered by accretion onto rotating super-massive black holes which create relativistic jets along the spin axis, though the detailed mechanism of this process still remains elusive. The jets in Blazars are aligned at a small angle to the line of sight, with the result that relativistic beaming dramatically boosts the apparent luminosity and variability. One avenue for progressing our understanding of jet production is provided by the Fermi Gamma-ray Space Telescope, which continuously monitors all gamma-ray bright Blazars, allowing an unprecedented opportunity for the systematic study of Blazar jets. The exact location of the gamma-ray emission region and its proximity to the central black hole remain subjects of debate, with two main competing classes of models for the GeV emission region. Testing these models requires a multiwavelength approach, combining the Fermi observations with supporting radio observations from OVRO-40m to search for correlations in the light curves at different frequencies.