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On the Origin of Faint Intracluster Starlight in Coma

Vladimir Korchagin·Toshio Tsuchiya·Shoken M. Miyama
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Abstract

Using N-body numerical simulations, we examine possible mechanisms for the origin of the intracluster starlight features recently discovered in the Coma cluster of galaxies. We show that tidal interactions of a ``normal'' elliptical galaxy with a symmetrically distributed dark matter potential do not produce the observed intracluster starlight features. A head-on collision of two normal ellipticals does, however, explain the origin of the intracluster features with surface brightness about 26 mag/arcsec$^2$). Another possible explanation for the intracluster starlight features is galactic tidal interactions with massive intracluster substructures. The presence of substructures in Coma with a density of $\sim$ 0.1 times the density in the center of the galaxy, and with a total mass about three orders of magnitude larger than the mass of a normal elliptical galaxy, would account for the observations.

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Vladimir Korchagin, Toshio Tsuchiya, Shoken M. Miyama. 2000-11-17. On the Origin of Faint Intracluster Starlight in Coma. https://doi.org/10.1086/319086

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