RUI: Low-Frequency Studies of Active Extragalactic Radio Sources

本项目的目标是记录低频 （频率小于1 GHz）可变特性 河外射电源 这些数据将与 已经提出的各种机制的预测 为了这个活动。 这些机制可分为： a）相对论演化源的固有可变性， 和 B）由于在光散射或吸收中的外在可变性。 介入介质。 为了在假设之间做出决定，观察将 开展这些活动的目的是： a）继续定期测量 低频（318兆赫）射电源通量密度 和430 MHz）， B）在低分辨率下获得源的高分辨率图像， 频率（327 MHz）使用甚长基线干涉测量 （VLBI），以及 c）在下列地点获得这些源的低频（327 MHz）图像： 甚大阵列（VLA） 该数据库将通过与以下机构合作获得的数据加以扩充： 其他工作在无线电和光波长的小组。 本科生和研究生的参与， 该项目涉及国际合作和利用 现代和复杂的技术，代表了他们 具有挑战性和回报的机会。

The objective of this project is to document the low frequency (frequency less than 1 GHz) characteristics of variable extragalactic radio sources. These data will be compared with the predictions of the various mechanisms which have been proposed for this activity. These mechanisms can be divided into: a) Intrinsic variability of a relativistically evolving source, and b) Extrinsic variability due to scattering or absorption in the intervening medium. In order to decide between the hypotheses, observations will be carried out to: a) Continue with the periodic measurements of the flux density of radio sources at low frequencies (318 MHz and 430 MHz), b) Obtain high resolution images of the sources at low frequencies (327 MHz) using Very Long Baseline Interferometry (VLBI), and c) Obtain low frequency (327 MHz) images of these sources at the Very Large Array (VLA). The data base will be augmented by data from a collaboration with other groups working at radio and optical wavelengths. The participation of undergraduate and graduate students in this project, which involves international cooperation and the use of modern and sophisticated techniques, represents for them challenging and rewarding opportunities.