射电天文研究室知识库

The 1(10)-1(11) formaldehyde (H2CO) absorption line and H-110 alpha radio recombination line (H RRL) are observed towards the giant HIT region in cloud complex W43. The observations are obtained using the Nanshan 25 m single dish operated by Urumqi Observatory, National Astronomical Observatories of China. A region about 30' x 30' is observed, which covers the whole HII region in W43. Except for the central 10' region, all the other seven points are first observed with the H2CO 1(10)-1(11) absorption. The column density of the H2CO is calculated, and the H2CO density contours show some differences with the infrared image. Multiple features appear in the H2CO and H RRL which indicate complex structure. The intensities of the H2CO and the velocities of the H-110 alpha seem to present a linear correlation, which illustrates that the sphere of influence of the central WR/OB cluster may be much more extended than presently known, since the size is nearly 50 pc.