1 / 20

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). The Exercise. 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)

shalin
Download Presentation

MOS Pn cross calibration with a sample of Galaxy Clusters

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

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

  2. The Exercise 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) All reduced with SAS 6.0 (rerun with 6.1 to begin soon) Emchain & Epchain correction for OOT applied Effective areas generated using arfgen with extended source options Rmfs generated using rmfgen MOS1, MOS2 (pattern 0-12) and pn (0-4) flag==0 for MOS and pn

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

  4. 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 χ2 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? 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? 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 • For each band comparison btwn detectors. • For each detector comparison btwn T measures in different bands

  7. MOS1 vs MOS2 mean = -0.064

  8. MOS1 vs MOS2 mean = -0.054

  9. MOS1 vs MOS2 mean = -0.075

  10. MOS1 vs pn mean = 0.063

  11. MOS1 vs pn mean = -0.007

  12. MOS1 vs pn mean = -0.18

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

  14. For each band comparison btwn detectors. • For each detector comparison btwn T measures in different bands

  15. 2-10 keV vs 1.5-10 keV N of obj (T2-10-T1.5-10)/T1.5-10

  16. 0.5-10 keV vs 1.5-10 keV N of obj (T0.5-10-T1.5-10)/T1.5-10

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

  18. 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

  19. SAS 6.0 -> 6.1

  20. Summary In the hard bands we have reasonable agreement btwn instruments, better than 10% 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. Pn changes in SAS 6.1 solve only part of the problem

More Related