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arXiv · 1603.05666

The Population of Compact Radio Sources in the Orion Nebula Cluster

Jan Forbrich·Victor M. Rivilla·Karl M. Menten·Mark J. Reid·Claire J. Chandler·Urvashi Rau·Sanjay Bhatnagar·Scott J. Wolk·Stefan Meingast
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Abstract

We present a deep centimeter-wavelength catalog of the Orion Nebula Cluster (ONC), based on a 30h single-pointing observation with the Karl G. Jansky Very Large Array in its high-resolution A-configuration using two 1 GHz bands centered at 4.7 GHz and 7.3 GHz. A total of 556 compact sources were detected in a map with a nominal rms noise of 3 muJy/bm, limited by complex source structure and the primary beam response. Compared to previous catalogs, our detections increase the sample of known compact radio sources in the ONC by more than a factor of seven. The new data show complex emission on a wide range of spatial scales. Following a preliminary correction for the wideband primary-beam response, we determine radio spectral indices for 170 sources whose index uncertainties are less than +/-0.5. We compare the radio to the X-ray and near-infrared point-source populations, noting similarities and differences.

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Jan Forbrich, Victor M. Rivilla, Karl M. Menten, Mark J. Reid, Claire J. Chandler, Urvashi Rau, Sanjay Bhatnagar, Scott J. Wolk, Stefan Meingast. 2016-03-17. The Population of Compact Radio Sources in the Orion Nebula Cluster. https://doi.org/10.3847/0004-637x/822/2/93

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