CO versus HI in the Tully-Fisher relation for a sample of 32 galaxies

F. Schoeniger; Y. Sofue

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arXiv · astro-ph/9308038

CO versus HI in the Tully-Fisher relation for a sample of 32 galaxies

F. Schoeniger·Y. Sofue

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Abstract

As a basic step for establishing the CO-line Tully-Fisher relation for distant galaxies, we made a comparative study of HI versus CO line profiles. Total line profiles of the CO line emission from 32 galaxies have been compared with the corresponding HI emission. We found a good correlation between the profiles of CO and HI. This strongly supports the thesis that CO can be used in the Tully-Fisher relation for distant galaxies where HI observations cannot reach. We also argue that CO can be used as an alternative to HI for un-isolated galaxies such as those in dense cluster of galaxies. Using the B-magnitudes and a recent calibration of the HI Tully-Fisher relation, we give the distances for the galaxies derived from the CO-line Tully-Fisher relation and compare them with the corresponding HI distances.

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F. Schoeniger, Y. Sofue. 1993-08-27. CO versus HI in the Tully-Fisher relation for a sample of 32 galaxies. https://arxiv.org/abs/astro-ph/9308038

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