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تسجيل مستخدم جديدStatistical Properties of Molecular Clumps in the Galactic Center 50 km s$^{-1}$ Molecular Cloud
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We present the statistical properties of molecular clumps in the Galactic center 50 km s$^{-1}$ molecular cloud (GCM-0.02-0.07) based on observations of the CS $J=1-0$ emission line with the Nobeyama Millimeter Array. In the cloud, 37 molecular clumps with local thermal equilibrium (LTE) masses of $2times10^2-6times10^3 M_odot$ were identified by using the {it clumpfind} algorithm. The velocity widths of the molecular clumps are about five-fold those of Galactic disk molecular clouds with the same radius. The virial-theorem masses are three-fold the LTE masses. The mass and size spectra can be described by power laws of $dN/dMpropto M^{-2.6pm0.1}$ ($Mgtrsim 900M_odot$) and $dN/dRpropto R^{-5.9pm0.3}$ ($Rgtrsim 0.35$ pc), respectively. The statistical properties of the region interacting with the Sgr A East shell and those of the non-interacting part of the cloud are significantly different. The interaction probably makes the mass function steeper, from $dN/dMpropto M^{-2.0pm0.1}$ in the non-interacting part to $dN/dMpropto M^{-4.0pm0.2}$ in the interacting region. On the other hand, the interaction presumably truncates the size spectrum on the larger side of $Rsim 0.4$ pc.
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