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arXiv · 1005.4823

An improved method for statistical studies of the internal kinematics of HII regions: the case of M 83

Javier Blasco-Herrera·Kambiz Fathi·John E. Beckman·Leonel Gutiérrez·Andreas Lundgren·Benoit Epinat·Göran Östlin·Joan Font·Olivier Hernandez·Marie-Maude de Denus-Bailargeon·Claude Carignan
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Abstract

We present the integrated Halpha emission line profile for 157 HII regions in the central 3.4' x 3.4' of the galaxy M 83 (NGC 5236). Using the Fabry-Perot interferometer GHaFaS, on the 4.2 m William Herschel on La Palma, we show the importance of a good characterization of the instrumental response function for the study of line profile shapes. The luminosity-velocity dispersion relation is also studied, and in the log(L)-log(sigma) plane we do not find a linear relation, but an upper envelope with equation log(L)=0.9 *log(sigma)+38.1. For the adopted distance of 4.5 Mpc, the upper envelope appears at the luminosity L=10^38.5 ergs, in full agreement with previous studies of other galaxies, reinforcing the idea of using HII regions as standard candles.

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Javier Blasco-Herrera, Kambiz Fathi, John E. Beckman, Leonel Gutiérrez, Andreas Lundgren, Benoit Epinat, Göran Östlin, Joan Font, Olivier Hernandez, Marie-Maude de Denus-Bailargeon, Claude Carignan. 2010-05-26. An improved method for statistical studies of the internal kinematics of HII regions: the case of M 83. https://doi.org/10.1111/j.1365-2966.2010.17078.x

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