Dust in the Circumgalactic Medium of Low-Redshift Galaxies

Abstract

Using spectroscopically selected galaxies from the Sloan Digital Sky Survey we present a detection of reddening effects from the circumgalactic medium of galaxies which we attribute to an extended distribution of dust. We detect the mean change in the colors of "standard crayons" correlated with the presence of foreground galaxies at z 0.05 as a function of angular separation. Following Peek & Graves, we create standard crayons using passively evolving galaxies corrected for Milky Way reddening and color-redshift trends, leading to a sample with as little as 2% scatter in color. We devise methods to ameliorate possible systematic effects related to the estimation of colors, and we find an excess reddening induced by foreground galaxies at a level ranging from 10 to 0.5 mmag on scales ranging from 30 kpc to 1 Mpc. We attribute this effect to a large-scale distribution of dust around galaxies similar to the findings of Ménard et al. We find that circumgalactic reddening is a weak function of stellar mass over the range M 6 10 9  -M 6 10 10  and note that this behavior appears to be consistent with recent results on the distribution of metals in the gas phase. We also find that circumgalactic reddening has no detectable dependence on the specific star formation rate of the host galaxy.

The dust content of galaxies from z = 0 to z = 9

“…The amount of dust in the hot halo is comparable to or even larger than the amount of dust in the ISM for galaxies with stellar masses of ∼ 10 10 M and larger. Our predictions are in the same mass range as the observational constraints derived by Peek, Ménard & Corrales (2015). However, we find a distinct difference between our model predictions and the Peek et al results for the slope between central galaxy stellar mass and CGM dust mass.…”

“…the dust in the CGM, we can compare our model predictions to recent observations (Ménard et al 2010;Peek, Ménard & Corrales 2015).…”

“…Figure 10 shows that the density of dust in the hot halo and ejected reservoir is always higher than the density of dust in the cold gas, especially at redshifts z < 1.5. These predictions suggest that a large fraction of the dust (and metals) ever formed may be stored outside galaxies (Peeples et al 2014;Peek, Ménard & Corrales 2015). If we can quantify these reservoirs observationally (for instance through reddening studies around galaxies or by looking at absorbers along quasar lines of sight) , this will provide unique additional constraints for the ejective feedback recipes in galaxy formation models.…”

“…Dust contributes significantly to the metals in the circumgalactic medium (CGM) and can be an additional cooling channel for gas (e.g. Ostriker & Silk 1973;Ménard et al 2010;Peeples et al 2014;Peek, Ménard & Corrales 2015).…”

Dust formation in Milky Way-like galaxies

“…The surfaces of dust grains play host to a range of chemical reactions that subsequently influence the behaviour of the ISM and impact star formation (Hollenbach & Salpeter 1971;Mathis 1990;Li & Draine 2001;Draine 2003). Additionally, observations suggest that dust is a significant contributor of metals in the circumgalactic medium (CGM; Bouché et al 2007;Peeples et al 2014;Peek, Ménard & Corrales 2015). Understanding the life cycle of dust grains, including their production in asymptotic giant branch (AGB) stars and supernovae (SNe ;Gehrz 1989;Todini & Ferrara 2001;Nozawa et al 2003;Ferrarotti & Gail 2006;Nozawa et al 2007;Zhukovska, Gail & Trieloff 2008;Nanni et al 2013;Schneider et al 2014), growth via accretion of gas particles in the ISM and coagulation with other dust particles (Draine 1990;Dominik & Tielens 1997;Dwek 1998; E-mail: ryanmck@mit.edu Hirashita & Kuo 2011), destruction via thermal sputtering, collisions with other dust grains, and SN shocks (Draine & Salpeter 1979a,b;McKee 1989;Jones, Tielens & Hollenbach 1996;Bianchi & Ferrara 2005;Yamasawa et al 2011), and other physical processes, is important in accurately modelling dust evolution.…”