1. Experience with combined Fe55 / Tycho SNR calibration
NRCO 71
EPIC Calibration & Operations Meeting
Mallorca, Spain, 2008 April 7 - 8

2. Internal calibration source onboard XMM-Newton / EPIC-pn
Al-K Mn-K

3. 30 ks in 2000
 210 ks in 2008
30 ks
10 ks

5. Experience with combined Fe55 / Tycho SNR calibration
General plan:
start with ‘normal’ Tycho observation
add the internal calibration source
finish with ‘normal’ calclosed observation
does the internal calibration source disturb the Tycho observation ?
does Tycho disturb the calclosed measurement ?
Unfortunately, this sequence was scheduled as three independent observations, performed in a non-contiguous mode
superposition with short-term changes in the absolute energy scale
no firm conclusions about potential changes of the absolute energy scale possible
however: general idea about ‘calopen’ observations

6. Experience with combined Fe55 / Tycho SNR calibration
1) Tycho FF Medium, / 19:55 – / 03:37, 27 ks

7. Experience with combined Fe55 / Tycho SNR calibration
2) Tycho FF Cal Medium, / 19:58 – / 09:59, 50 ks

8. Experience with combined Fe55 / Tycho SNR calibration
3) Calclosed, / 01:06 – / 08:11, 25 ks

9. 1) Tycho FF Medium, 2007-12-30 / 19:55 – 2007-12-31 / 03:37, 27 ks

10. 2) Tycho FF Cal Medium, 2008-01-01 / 19:58 – 2008-01-02 / 09:59, 50 ks

11. 3) Calclosed, 2008-01-03 / 01:06 – 2008-01-03 / 08:11, 25 ks

12. Narrow-line images at Mn-K: 5.70 – 6.05 keV
adu
ΔE = 350 eV

13. Narrow-line images at Mn-K: 5.70 – 6.05 keV
scaled to the same exposure time
ΔE = 0.35 keV
Tycho CalClosed Tycho + CalClosed

14. all energy bands centered on Mn-K
Tycho + CalClosed
all energy bands centered on Mn-K
ΔE = 0.35 keV
ΔE = 1.0 keV
ΔE = 2.0 keV
ΔE = 5.0 keV

15. Narrow-line images at Al-K: 1.375 – 1.575 keV
adu
ΔE = 200 eV

16. Narrow-line images at Al-K: 1.375 – 1.575 keV
scaled to the same exposure time
ΔE = 0.20 keV
Tycho CalClosed Tycho + CalClosed

17. calclosed

18. Tycho

19. Tycho + calclosed

20. Mn-K
calclosed

21. Mn-K
Tycho + calclosed

22. Al-K
calclosed

23. Al-K
Tycho + calclosed

24. CTI determination: Illustration of the Template Cross Correlation method (EPIC pn)
25 macro pixels,
20-29 singles per macro pixel

25. calclosed
CTI

26. Tycho + calclosed
CTI

27. Tycho + calclosed
CTI 

28. Experience with combined Fe55 / Tycho SNR calibration
Tycho + calclosed seems ok for Mn-K, but not for Al-K
Tycho better suited for LW than for FF
Calclosed & LW no useful combination
 are there celestial calibration targets which are better suited for a combined Fe55 exposure ?

29. Vela SNR

30. Vela SNR (62 ks)

31. calclosed (25 ks)

32. Vela SNR + calclosed (scaled to 62 ks)

33. Experience with combined Fe55 / Tycho SNR calibration
Vela + calclosed might be an interesting alternative:
the parts of the Vela SNR covered by the FOV are similarly extended as the internal calibration source
the X-ray surface brightness of the Vela SNR is similar to that of the internal calibration source
the X-ray spectrum of the Vela SNR is almost complementary to that of the internal calibration source
But the Al-K region would need to be checked in detail..