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arXiv · 1112.5975

Enhanced Abundances in Spiral Galaxies of the Pegasus I Cluster

Paul Robertson·Gregory A. Shields·Guillermo A. Blanc
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Abstract

We study the influence of cluster environment on the chemical evolution of spiral galaxies in the Pegasus I cluster. We determine the gas-phase heavy element abundances of six galaxies in Pegasus derived from H II region spectra obtained from integral-field spectroscopy. These abundances are analyzed in the context of Virgo, whose spirals are known to show increasing interstellar metallicity as a function of H I deficiency. The galaxies in the Pegasus cluster, despite its lower density and velocity dispersion, also display gas loss due to ISM-ICM interaction, albeit to a lesser degree. Based on the abundances of 3 H I deficient spirals and 2 H I normal spirals, we observe a heavy element abundance offset of +0.13\pm0.07 dex for the H I deficient galaxies. This abundance differential is consistent with the differential observed in Virgo for galaxies with a similar H I deficiency, and we observe a correlation between log(O/H) and the H I deficiency parameter DEF for the two clusters analyzed together. Our results suggest that similar environmental mechanisms are driving the heavy element enhancement in both clusters.

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Paul Robertson, Gregory A. Shields, Guillermo A. Blanc. 2011-12-27. Enhanced Abundances in Spiral Galaxies of the Pegasus I Cluster. https://doi.org/10.1088/0004-637x/748/1/48

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