摘要
使用全球ＶＬＢＩ网在１．３ ｃｍ波段对三颗类星体０４２０－０１４、０７４８＋１２６和２２５１＋１５８（３Ｃ ４５４．３）进行了观测，获得了这三个类星体的亚毫角秒分辨率的混杂图，给出了类星体核区内的亮度分布．通过用高斯模型对观测数据进行拟合，得到了组成它们的各个子源的参数．类星体２２５１＋１５８呈现出核－喷流结构，核区沿着ＰＡ～－１３０°方向拉长，喷流呈弯曲状．１９９２．９历元的观测展现了２２５１＋１５８处于一次大爆发，并伴随一系列相继出现的小爆发的情景．最强子源的积分流量密度为 ４．１１Ｊｙ（占探测到的总流量的 ６７％），主要集中在０．１６ × ０．０１ ｍａｓ的区域内，可能由于多普勒增亮效应造成高达２．６×１０１２的亮温度．
The quasars, 042M14, 0748+126 and 2251+158 (3C 454.3), have been observed at 1 .3 cm with a global VLBI network. We have obtained the hybrid maps of the quasars at submilliarcsecond resolution. The brightness distribution is revealed in their nuclear regions. The observed data are fitted with a small number of Gaussian components. 2251+158 shows a core-jet structure, and its nuclear region is elongated in the direction PA= -130° The jet is curved. Its observations at the epoch 1992.9 show it to be in the course of a large burst, accompanied by several smaller ones. The strongest component has a flux of ~ 4.11 Jy (67% of the total detected flux), mostly from an area of 0.16× 0.01 mas. Doppler boosting is probably responsible for raising the brightness temperature up to 2.6× 1012 K.
基金
国家攀登计划资助
关键词
类星体
射电发射
亚毫角秒结构
quasar-radio emission-sub- milliarcsecond structure
