VIBI Observations of Two Quasars at 1.3cm

The quasars, 0748+126 and 2251+158 (3C 454 3),have been observed at 1 3cm by using a global VLBI network. We have obtained the images of the quasars with a resolution higher than 0″ 001. The brightness distribution is revealed in the nuclear region of the quasars. The radio emission FWHM from 0748+126 is 0 61×0 27 mas. 2251+158 shows a nucleus-jet structure, and the nuclear region is elongated in the direction PA=-130°, The quasar can be fitted with 4 Gaussian components. The most west and east components are separated by 0 8mas (3pc). The integrated flux density in the nuclear region is 6 138Jy. The most east component shows the highest brightness, and its flux is ～4 11Jy (in 67% of the total detected flux), concentrated in the area of 0 16×0 01 mas. This causes the brightness temperature up to 2 6×10 12 K.

1.3厘米接收机背架调整系统设计

基于新疆天文台研制的1.3 cm双极化制冷接收机的安装及观测需求,设计了其背架调整系统。首先,通过力学分析选择合适的滚珠丝杠及驱动电机;其次,通过对电机进行测试,研制电机驱动模块,以满足安装要求;最后,编写电机驱动控制软件,实现终端对接收机馈源的精确控制。