Ammonia observations of the nearby molecular cloud MBM 12
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چکیده
We present NH3(1,1) and (2,2) observations of MBM 12, the closest known molecular cloud (65 pc distance), aimed to find evidence for on-going star formation processes. No local temperature (with a Trot upper limit of 12 K) nor linewidth enhancement is found, which suggests that the area of the cloud we mapped (∼ 15 size) is not currently forming stars. Therefore, this close “starless” molecular gas region is an ideal laboratory to study the physical conditions preceding new star formation. A radio continuum source was found in Very Large Array archive data, close but outside the NH3 emission. This source is likely to be a background object.
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تاریخ انتشار 2008