1. MOS Pn cross calibration with a sample of Galaxy Clusters MOS Pn cross calibration with a sample of Galaxy Clusters Alberto Leccardi & Silvano Molendi (IASF-MI)

2. The Exercise The Exercise Sample of 21, high gal latitude, hot, intermediate redshift Galaxy Clusters observed with XMM-Newton.Sample of 21, high gal latitude, hot, intermediate redshift Galaxy Clusters observed with XMM-Newton. About 80 high quality spectra (bkg is not an issue)About 80 high quality spectra (bkg is not an issue) All reduced with SAS 6.0 (rerun with 6.1 to begin soon)All reduced with SAS 6.0 (rerun with 6.1 to begin soon) Emchain & Epchain correction for OOT appliedEmchain & Epchain correction for OOT applied Effective areas generated using arfgen with extended source optionsEffective areas generated using arfgen with extended source options Rmfs generated using rmfgenRmfs generated using rmfgen MOS1, MOS2 (pattern 0-12) and pn (0-4)MOS1, MOS2 (pattern 0-12) and pn (0-4) flag==0 for MOS and pnflag==0 for MOS and pn

3. Spectral accumulated in concentric annuli (from 5 to 8 depending on source SB). Important for testing full FOV MOS1 image of A1689 The Exercise

4. Which band? Which band? Testing spectral calibration with thermal spectra is somewhat different than with power-laws. For high T (kT > 4keV) the scientific valuable information is all in the hard band, however for EPIC and many other X-ray experiments most of the statistics is in the softer band. Performing spectral fits using a cumulative statistics such as χ 2 on a broad band will put lots of weight on the insensitive soft part of the spectrum and relatively less on the hard scientifically important part.

5. Which band? Which band? Two possible points of view Observer: forget the soft band, it only cmplicates things! Calibrator: if I can get the right temperature fitting the broad band than my calibration must really be good! Spectral fits in 0.5-10 keV 1.5-10 keV 2-10 keV

6. Which band? Which band? Spectral fits in 0.5-10 1.5-10 2-10 for MOS1 and MOS2 0.5-7.3 1.5-7.3 2-7.3 for pn 1. 1.For each band comparison btwn detectors. 2. 2.For each detector comparison btwn T measures in different bands

7. A typical case: A3921 A typical case: A3921 MOS1

8. MOS2 MOS2

9. Pn Pn Instrumental background is a key issue that has not enjoyed sufficent attention in planning X-ray experiments. Let’s see how it may be addressed

10. MOS1 vs MOS2 MOS1 vs MOS2 mean = -0.064

11. MOS1 vs MOS2 MOS1 vs MOS2 mean = -0.054

12. MOS1 vs MOS2 MOS1 vs MOS2 mean = -0.075

13. MOS1 vs pn MOS1 vs pn mean = 0.063

14. MOS1 vs pn MOS1 vs pn mean = -0.007

15. MOS1 vs pn MOS1 vs pn mean = -0.18

16. Summary MOS vs pn Summary MOS vs pn 1.For hard bands reasonable agreement btwn all instruments. 2.Broad band MOS and PN are clearly discrepant

17. 1. 1.For each band comparison btwn detectors. 2. 2.For each detector comparison btwn T measures in different bands

18. 2-10 keV vs 1.5-10 keV 2-10 keV vs 1.5-10 keV (T 2-10 -T 1.5-10 )/T 1.5-10 N of obj

19. 0.5-10 keV vs 1.5-10 keV 0.5-10 keV vs 1.5-10 keV (T 0.5-10 -T 1.5-10 )/T 1.5-10 N of obj

20. Summary Summary 1.T drops as you include softer parts of the spectrum (at least part of this is not due to calibration) 2. the Pn temperatures vary considerably more than the MOS T 3.Bigest problem is 20% pn variation when going from 1.5-10 keV to 0.5-10 keV

21. SAS 6.0 -> 6.1 SAS 6.0 -> 6.1 For one object A2199 we compared old and new SAS 0.5-10 keV (filled circles) vs 1.5-10 keV empty circles SAS 6.0 SAS 6.1

22. SAS 6.0 -> 6.1 SAS 6.0 -> 6.1

23. Summary Summary 1.In the hard bands we have reasonable agreement btwn instruments, better than 10% 2.In the soft band there is a large discrepancy btwn. MOS and pn, the fact that pn in 1.5-10 keV and pn in 0.5- 10 keV show a similar discrepancy indicates that the problem is a pn rather than a MOS problem. 3.Pn changes in SAS 6.1 solve only part of the problem