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تسجيل مستخدم جديدThe ATCA HI Galactic Center Survey
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We present a survey of atomic hydrogen HI) emission in the direction of the Galactic Center conducted with the CSIRO Australia Telescope Compact Array (ATCA). The survey covers the area -5 deg < l < +5, -5 deg < b <+5 deg over the velocity range -309 < v_{LSR} < 349 km/s with a velocity resolution of 1 km/s. The ATCA data are supplemented with data from the Parkes Radio Telescope for sensitivity to all angular scales larger than the 145 arcsec angular resolution of the survey. The mean rms brightness temperature across the field is 0.7 K, except near (l,b)=(0 deg, 0 deg) where it increases to ~2 K. This survey complements the Southern Galactic Plane Survey to complete the continuous coverage of the inner Galactic plane in HI at ~2 arcmin resolution. Here we describe the observations and analysis of this Galactic Center survey and present the final data product. Features such as Banias Clump 2, the far 3 kiloparsec arm and small high velocity clumps are briefly described.
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