École Nationale Supérieure de
Techniques Avancées

Abstract

Context: The specific angular momentum seems to be a parameter that characterizes galaxies. Furthermore, isolated galaxies are free of interactions. Then in this paper we study the specific angular momentum of isolated galaxies. Aims: We establish in this work two scaling relations using the isolated galaxies from the CIG (catalog of isolated galaxies) sample: The relation between HI asymmetry and specific angular momentum and the relation between mass and specific angular momentum. The second one have been already established for all kinds of galaxies (not especially isolated). Finally, this works compare the obtained results with the reference results. Method: We used a simplified relation that allows to estimate the specific angular momentum for the isolated galaxies. Then we study the HI spectrum and we used the SDSS database in order to compute the specific angular momentum using the previous simplified relation. Result: No correlation has been highlighted between HI asymmetry and the specific angular momentum for the isolated galaxies. A correlation has been established between the mass and the specific angular momentum. It seems that, for a given mass, in average isolated galaxies have a greater specific angular momentum. Conclusion: We can conclude here that, as expected, the isolated galaxies have a greater specific angular momentum. Interactions with other galaxies absorb specific angular momentum. However, the low completeness of the sample and the several estimation did not allow us to conclude that it is absolutely true.