Isolated molecular clumps at the co-boundary of a diffuse molecular cloud

Defining boundaries of a molecular cloud is difficult given that different tracers of H2 indicate different cloud borders. Traditionally, the edge of a molecular cloud is defined by the lowest CO(1-0) contour in maps with typical rms values of 0.1 K in antenna temperature. However, molecular gas extends beyond that boundary and may be traced by other means (dust, OH, etc.). Nonetheless, sensitive CO(1-0) observations (rms 20 mK) by Donate & Magnani (2017) reveal a larger extent for the diffuse molecular cloud, MBM 53. The deep CO survey consisted of averaging 13 one-arcminute beams to simulate a larger beam. By analyzing each spectrum individually we can examine the Emission structure on smaller scales and identify four lines of sight where isolated CO clumps may be found. This molecular debris at the edges of a cloud may provide a way to study the structuring processes at the boundaries of these objects.