deletions | additions       diff --git a/observations.tex b/observations.tex  index 3eb6ff8..9a89ba1 100644  --- a/observations.tex  +++ b/observations.tex 
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The catalog includes the distance of each dwarf from both the MW and M31, and we define ``satellites'' as those within $300 \kpc$ of either host, motivated by the sharp transition in star formation, gas, and morphological properties within this distance.  $300 \kpc$ also coincides with the median virial radius, $\rvir$, for our simulated MW/M31 halos (see below).  In addition to the data in \citet{McConnachie2012}, we also include the more recent measurements or upper limits of cold atomic gas mass from \citet{Spekkens2014}.  We do not include the recently discovered ultra-faint satellites of the MW from the Dark Energy Survey \citet{Koposov2015,DES2015}. \citet{Koposov2015, DES2015}.  The observed dwarf galaxies show a tight correlation between their morphology, star formation, and cold gas content, such that all (?) of the dwarf spheroidals have little-to-no detectable gas ($\mgas / \mstar < 0.1$) or ongoing star formation, and all (?) of the dwarf irregulars have a significant fraction of their baryonic mass in cold gas and ongoing star formation.  Thus, we define ``quiescent'' satellites as those that have $\mgas / \mstar < 0.1$ or are classified as having spheroidal morphology if they have no cold gas constraints.  Thus, by this definition, the only star-forming, gas-rich satellites in the LG are: LMC ($\mstar = 1.5 \times 10^9 \msun$, $\mgas / \mstar \approx 0.3$) and SMC ($\mstar = 4.6 \times 10^8 \msun$, $\mgas / \mstar \sim 1$) around the MW, and LGS 3 ($\mstar = 9.6 \times 10 ^ 5 \msun$, $\mgas / \mstar \approx 0.4$) and IC 10 ($\mstar = 9 \times 10 ^ 7$, $\mgas / \mstar \approx 0.6$) around M31.  (While Sculptor has $\mgas / \mstar \approx 0.096$, we consider it quiescent based on its morphology and lack of recent star formation \citep{Weisz2014}). \citep{Weisz2014a}).  (Dan or Erik - can you say something about comparing these cuts with either SFR metrics or SFHs? Specifically, I am glossing over any ambiguous systems?)  In examining the fraction of satellites that are quiescent, we group them into 1-dex bins of $\mstar$.