ASCA results and re-directing my efforts

Last week I met with Kim about the Constellation-X web pages. I also brought her a preview of my ASCA results.

The point of running the ASCA data was to see if we could see the same structure in it’s data as the XTE data. If we could, it would be good confirmation that the structure is real rather than instrumentational. Unfortuantely, the ASCA data do not show the effect. However, after talking with Kim, we decided that it’s entirely possible that ASCA does not have enough response in the higher energeis to actually show the structure. To this end, I’m going to find average count rates for the various energy ranges for each instrument, and perhaps show statistically that ASCA can’t detect the structure.

Kim also suggested picking another type of source and use it as a control source. Ideally a cluster of galaxies would work, but unfortunately there aren’t many repeat observations of clusters in the XTE archive. Instead, I’m going to look at the Crab data spanning the same years as the MCG -6-30-15 data. If the structure is real, i.e. inherent to MCG -6-30-15, then we should not see it in the Crab data. However, if the structure is instrumentational, we will see it in the Crab data. My only concern is that the Crab is a “bright” source; whereas MCG -6-30-15 is a “faint” source. Different background models are used for extracting the background spectra and lightcurves for “bright” versus “faint” sources. Someone might argue that the structure is due to background modelling — not sure if that holds water, but might need to investigate.