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GMRT HI imaging survey of ERIDANUS group of galaxies

Amitesh Omar·K. S. Dwarakanath·K. R. Anantharamaiah
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Abstract

This project aims to image a subset of galaxies in the nearby group Eridanus in HI emission and in radio continuum using the GMRT. The typical resolution of HI images will be $\sim$1 kpc with a 3$σ$ sensitivity to HI mass of a few times 10$^{7}$ M$_\odot$. The rotation curves obtained using the HI velocity field together with the 2MASS magnitudes in the near infrared will be used to construct the Tully-Fisher relation for this group. High resolution (sub-kpc) multi-frequency radio continuum images will be used to study star-formation rates, radio morphologies and spectral indices of Eridanus galaxies. About half of the galaxies have already been observed and further observations on some late type galaxies are proposed with the GMRT. We present here the HI image and the rotation curve for a member of this group viz. NGC 1385.

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Amitesh Omar, K. S. Dwarakanath, K. R. Anantharamaiah. 2002-05-04. GMRT HI imaging survey of ERIDANUS group of galaxies. https://arxiv.org/abs/astro-ph/0205062

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