...
- Measuring CTI, ACIS vs XIS (methodology)
- ACIS – fit all grades, only center pixel pulseheight vs ccdy/ccdx (binning/fitting details needed)
- XIS – fit only good grades, summed pulseheight from top cal source corners
- process ACIS the same way as XIS for comparison? only use center pixels? CTI metric to be decided
- only use Mn K alpha
- include checker-flag CTI measurement for XIS, SCI-off (Ozawa 2009)
- CTI evolution, plots of measured CTI vs time
- for ACIS, apply corrections for temperature and sacrificial charge
- not done for XIS; temperature is stable, background is integrated over 1 day = 16 orbits
- decide on time binning
- not necessary to be the same for ACIS/XIS, and might be misleading given very different cal source duty cycles
...
- speculate on CTI/FWHM increase with regard to particle fluence, particle type
- maybe beyond scope of this paper
- -comparison of a celestial source
- E0102
- has been observed extensively over time with ACIS and XIS
- low energy lines very different from Mn K alpha
- mostly on ACIS-S3
- Perseus, other clusters
- check ACIS time coverage, XIS and ACIS roll angles
- Fe line centroid changes with kT, location in cluster-
- E0102
Comments from MWB
- outline quite broad, might want to focus it more
- (his) primary goal: understand the relationship between spectral resolution, radiation damage, and background
- frame-to-frame variations in BG lead to variations in trap filling and wobbling of LSF
- Suzaku especially good since we can already model the BG as a function of orbital position
- secondary goal: construct a model of the background
- test this model with a simulated BG (e.g. from Co60 source) in the lab (perhaps follow-up paper)