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arXiv · 1402.3394

The connection between galaxy structure and quenching efficiency

Conor Omand·Michael Balogh·Bianca Poggianti
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Abstract

Using data from the SDSS-DR7, including structural measurements from 2D surface brightness fits with GIM2D, we show how the fraction of quiescent galaxies depends on galaxy stellar mass $M_*$, effective radius $R_e$, fraction of $r-$band light in the bulge, $B/T$, and their status as a central or satellite galaxy at $0.01 0.3$ are excluded. For satellite galaxies, the quiescent fraction is always larger than that of central galaxies, for any combination of $M_*$, $R_e$ and $B/T$. The quenching efficiency is not constant, but reaches a maximum of $\sim 0.7$ for galaxies with $9 < \log(M_*/M_\odot) < 9.5$ and $R_e<1$ kpc. This is the same region of parameter space in which the satellite fraction itself reaches its maximum value, suggesting that the transformation from an active central galaxy to a quiescent satellite is associated with a reduction in $R_e$ due to an increase in dominance of a bulge component.

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Conor Omand, Michael Balogh, Bianca Poggianti. 2014-02-28. The connection between galaxy structure and quenching efficiency. https://doi.org/10.1093/mnras%2Fstu331

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