...
- about the orbits and backgrounds
- steal from Bev's 2008 SPIE paper
- steal from O'Dell, Markevitch papers on radiation environments
- about the calibration sources
- ACIS, Fe55 with Al&Ti (Fe-L), uniform illumination, getting pretty wimpy, only sampled twice per orbit
- XIS, Fe55 in corners, getting wimpy, continuously sampled (except SAA)
- measure Fe55 half-life extremely well
...