1. INTRODUCTION

2. SAMPLE

3. CONSTRUCTING STACKED IMAGES

4. ANALYSIS
4.1. Parameterizing the surface brightness profile

5. SIMULATIONS
5.1. Recovering total counts and fit parameters
5.2. Recovering counts within 50 kpc
5.3. Identifying extended emission
5.4. Effects of changing the PSF
5.5. Including a combination of point source and extended components
5.6. Summary of simulations

6. STATISTICAL SIGNIFICANCE OF DETECTIONS

7. RESULTS
7.1. Average Luminosity
7.3. X-ray binaries
7.4. The LX - LK relation
7.5. Hot Gas Mass
7.6. Comparison with previous work

8. CONCLUSIONS