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Polar Ring Galaxies and the Tully-Fisher relation

Magda Arnaboldi·Enrica Iodice·Frederick Bournaud·Francoise Combes·Linda S. Sparke·Wim van Driel·Massimo Capaccioli
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Abstract

We have investigated the Tully-Fisher relation for Polar Ring Galaxies (PRGs), based on near infrared, optical and HI data available for a sample of these peculiar objects. Many PRGs show larger HI line-widths than expected for the observed K band luminosity, and this result is confirmed by a larger sample of objects, based on B-band data. This observational evidence may be related to the dark halo shape and orientation in these systems: the larger rotation velocities observed in PRGs can be explained by a flattened polar halo, aligned with the polar ring.

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Magda Arnaboldi, Enrica Iodice, Frederick Bournaud, Francoise Combes, Linda S. Sparke, Wim van Driel, Massimo Capaccioli. 2003-10-06. Polar Ring Galaxies and the Tully-Fisher relation. https://arxiv.org/abs/astro-ph/0310139

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