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Morphology and kinematics of HI in dust-lane elliptical galaxies

Raffaella Morganti·Tom Oosterloo·Elaine Sadler·Daniela Vergani
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Abstract

We present the results of the HI observations of four dust-lane ellipticals. The HI detected is regularly distributed in disks or rings. Moreover, in three of the four objects we have detected a very large amount of neutral hydrogen with values of M_HI/L_B that are at the end of the distribution characteristic of ellipticals and similar to what typically found in spiral galaxies. Thus, these dust-lane ellipticals may represent the results of major mergers as seen at a late stage of the evolution. The regular HI distribution and kinematics has allowed to derive values of M/L_B~20 at distances of ~5 R_e from the centre. Evidence for an increase of the dark matter contribution at larger radii can also be derived from the flat rotation curves observed in some of the observed galaxies.

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Raffaella Morganti, Tom Oosterloo, Elaine Sadler, Daniela Vergani. 1998-09-07. Morphology and kinematics of HI in dust-lane elliptical galaxies. https://arxiv.org/abs/astro-ph/9809074

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