The Starburst in the Central Kiloparsec of Markarian 231

G. B. Taylor; C. S. Silver; J. S. Ulvestad; C. L. Carilli

doi:10.1086/307362

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arXiv · astro-ph/9902082

The Starburst in the Central Kiloparsec of Markarian 231

G. B. Taylor·C. S. Silver·J. S. Ulvestad·C. L. Carilli

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Abstract

We present VLBA observations at 0.33 and 0.61 GHz, and VLA observations between 5 and 22 GHz, of subkiloparsec scale radio emission from Mrk 231. In addition to jet components clearly associated with the AGN, we also find a smooth extended component of size 100 - 1000 pc most probably related to the purported massive star forming disk in Mrk 231. The diffuse radio emission from the disk is found to have a steep spectrum at high frequencies, characteristic of optically thin synchrotron emission. The required relativistic particle density in the disk can be produced by a star formation rate of 220 Msolar/yr in the central kiloparsec. At low frequencies the disk is absorbed, most likely by ionized gas with an emission measure of 8 x 10^5 pc cm-6. We have also identified 4 candidate radio supernovae that, if confirmed, represent direct evidence for ongoing star formation in the central kiloparsec.

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G. B. Taylor, C. S. Silver, J. S. Ulvestad, C. L. Carilli. 1999-02-04. The Starburst in the Central Kiloparsec of Markarian 231. https://doi.org/10.1086/307362

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