Variability of the Intensity, Structure, and Magnetic Field in Compact Blazar Jets

AST 98-02941 Marscher虽然在探索类星体的性质方面已经取得了很大的进展，但它们现在只被部分理解。与类星体有关的高能现象被认为是由吸积提供动力的，只有位于宿主星系中心的大质量黑洞。燃料可能是穿过星系核的星际气体，可能是与另一个星系相遇的结果。吸积气体的角动量使它形成一个围绕黑洞的差速旋转盘。在其中的一些天体中--尤其是那些位于椭圆星系中心的天体--磁化的超相对论等离子体射流以接近光速的速度沿着圆盘的旋转轴沿着向外流动。Marscher博士正在研究在一些类星体中观察到的具有高度可变非热辐射的射电喷流的性质。这些天体是Blazars类的一部分。Marscher博士正在将实际喷流的高分辨率、高频无线电图像与通过流体动力学计算获得的模拟喷流图像进行比较。观测将跟踪新的结沿着喷流的传播（大约每月从核心喷出）。核心本身的性质也被探索，以及磁场的结构。***

AST 98-02941 Marscher Although much progress has been made in exploring the nature of quasars, they are now only partly understood. The energetic phenomena associated with quasars are thought to be powered by accretion only massive black holes lying at the centers of the host galaxies. The fuel would be interstellar gas that passes through the nucleus of the galaxy, probably as a result of an encounter with another galaxy. The angular momentum of the accreting gas causes it to form a differentially rotating disk surrounding a black hole. In some of these objects - preferentially those that lie at the centers of elliptical galaxies - jets of magnetized ultrarelativistic plasma flow outward at speeds near that of light along the rotation axis of the disk. Dr. Marscher is studying the nature of the radio jets with highly variable nonthermal radiation that are observed in some quasars. These objects are part of the class known as Blazars. Dr. Marscher is comparing high-resolution, high-frequency radio images of actual jets with images of simulated jets obtained through hydrodynamic calculations. The observations will follow propagation of new knots down the jets (ejected roughly monthly from the core). The nature of the core itself is also explored, and the structure of the magnetic field. ***