Comets observed with XMM-Newton

Transcription

1 A major step in cometary X-ray research Konrad Dennerl Max-Planck-Institut für extraterrestrische Physik

2 Comets the most surprising X-ray objects in space

3 1996: Comet Hyakutake (C/1996 B2) EPIC Consortium Meeting, K. Dennerl Comets observed with XMM XMM--Newton Palermo/ Italy Italy,, 2003 O c t

4

5

6

7

8 distance [AU] distance [AU]

9 Hyakutake Hale -Bopp

10

11 Hyakutake Hale -Bopp

12 More gas per dust X-ray luminosity Hyakutake Hale -Bopp Optical luminosity (dominated by dust)

13

14 ROSAT PSPC spectra of comet Levy

15 Heavy ions in the solar wind.. and X-rays from comets

16 Cravens 2002, Science 296

17 how charge exchange works H 2 O 561 ev Charge exchange De-excitation O 7+ O 6+* O 6+

18 Main characteristics of solar wind charge exchange interactions High cross section Most parts of coma collisionally thick, but optically thin for X-rays peak X-ray flux determined by the supply of heavy ions in the solar wind X-ray size determined by the gas production rate of the comet

19 Classical over-the-barrier model the electron is able to cross over from the target to the projectile for the favored principal quantum number Ryufuku et al Mann et al Cravens 2002 Cravens 2002, Science 296

20 Charge transfer: theoretical approaches COB: classical over-the-barrier model most elementary approach gives an estimate of the capture cross section into the classically most likely n-level not capable of predicting the distribution of states (n,l-levels) after capture CTMC: classical trajectory Monte Carlo technique more elaborate simulation at the level of classical mechanics takes the three-body dynamics (projectile ion, target ion, and one active target electron) into account LZ: Landau-Zener approximation elucidates general behaviour of the cross sections and can estimate state-selective capture however, of limited accuracy CC: quantum-mechanical close-coupling method capable of treating the relevant atomic and/or quasi-molecular structure and reaction dynamics however, treatment of the pertinent range of systems and channels very challenging to both technique and computational resources Hasan et al. 2001, ApJ 560

21 Charge transfer: theoretical approaches Current state: Certain of the magnitudes and trends of the experimental measurements can be predicted by simple quasi-classical models, but further work is needed to devise tractable quantum models to cover the wide range of ion species, velocities, charge states, and molecular targets required forbetter agreement with benchmark experiments. Hasan et al. 2001, ApJ 560

22 2 P 1/2,3/2 5p 2 P 1/2,3/2 4p 836 ev 816 ev 3 P 1/2,3/2 3p 774 ev 1 P 1 1s 4p 2 P 2 1/2,3/2 S 1/2 2p 2s 3 P 0,1,2 1s 3p 1 P 1 1s 3p 654 ev 654 ev / 19.0 A 3 P 0,1,2 1s 2p 3 S 1 1s 2s 1 P 1 1s 2p 1 S 0 1s 2s 574 ev / 21.6 A r i f 561 ev / 22.1 A 568 ev / 21.8 A 1 S 0 1s 1 S 0 1s 2

23

24 July 2000: first direct detection of charge exchange induced line emission with Chandra ACIS-S

25 XMM-Newton observation of Comet C/1999 T1 (McNaught-Hartley) heliocentric latitude: +30 deg

26

27

28

29 XMM-Newton observation of Comet C/1999 T1 (McNaught-Hartley) EPIC MOS 1 + MOS 2 + PN

30 t obs t = obs Dec Dec13/14 m v = v mag mag dist dist Sun = Sun AU AU dist dist Earth = Earth AU AU phase = deg deg elong = deg deg hel. hel. lat. lat. = deg deg

31 XMM-Newton observation of Comet C/2000 WM1 raw image contaminated by variable exposure due to moving FOV temporally variable vignetting trails of X-ray point sources trails of bright pixels EPIC pn comet coordinates

32 XMM-Newton observation of Comet C/2000 WM1 all events EPIC MOS 1 detector coordinates

33 XMM-Newton observation of Comet C/2000 WM1 all events EPIC MOS 1 detector coordinates events in bright pixels removed

34 XMM-Newton observation of Comet C/2000 WM1 exposure map EPIC MOS 1 detector coordinates

35 XMM-Newton observation of Comet C/2000 WM1 exposure map EPIC MOS 1 detector coordinates bright pixels removed

36 XMM-Newton observation of Comet C/2000 WM1 EPIC MOS 1 sky coordinates background map bright pixels removed exposure map bright pixels removed

37 XMM-Newton observation of Comet C/2000 WM1 EPIC MOS 1 sky coordinates hard X-ray image ( E > 1 kev ) events in bright pixels removed soft X-ray image ( E < 1 kev ) events in bright pixels removed

38 XMM-Newton observation of Comet C/2000 WM1 EPIC MOS 1 sky coordinates hard X-ray image ( E > 1 kev ) events in bright pixels removed events around point sources removed soft X-ray image ( E < 1 kev ) events in bright pixels removed events around point sources removed

39 XMM-Newton observation of Comet C/2000 WM1 EPIC MOS 1 sky coordinates background map bright pixels removed exposure map bright pixels removed

40 XMM-Newton observation of Comet C/2000 WM1 EPIC MOS 1 sky coordinates background map bright pixels removed regions around point sources removed exposure map bright pixels removed regions around point sources removed

41 XMM-Newton observation of Comet C/2000 WM1 EPIC pn sky coordinates background map bright pixels removed exposure map bright pixels removed

42 XMM-Newton observation of Comet C/2000 WM1 EPIC pn sky coordinates hard X-ray image ( E > 1 kev ) events in bright pixels removed soft X-ray image ( E < 1 kev ) events in bright pixels removed

43 XMM-Newton observation of Comet C/2000 WM1 EPIC pn sky coordinates hard X-ray image ( E > 1 kev ) events in bright pixels removed events around point sources removed soft X-ray image ( E < 1 kev ) events in bright pixels removed events around point sources removed

44 XMM-Newton observation of Comet C/2000 WM1 EPIC pn sky coordinates background map bright pixels removed regions around point sources removed exposure map bright pixels removed regions around point sources removed

45 XMM-Newton observation of Comet C/2000 WM1 background map for one pointing bright pixels removed regions around point sources removed EPIC MOS 1 EPIC pn comet coordinates

46 XMM-Newton observation of Comet C/2000 WM1 background map for all pointings bright pixels removed regions around point sources removed EPIC MOS 1 EPIC pn comet coordinates

47 XMM-Newton observation of Comet C/2000 WM1 exposure map for all pointings bright pixels removed regions around point sources removed EPIC MOS 1 EPIC pn comet coordinates

48 XMM-Newton observation of Comet C/2000 WM1 exposure corrected comet image bright pixels removed regions around point sources removed EPIC MOS 1 EPIC pn comet coordinates

49 XMM-Newton observation of Comet C/2000 WM1 exposure corrected comet image bright pixels removed regions around point sources removed EPIC MOS 1 EPIC pn comet coordinates

50 XMM-Newton observation of Comet C/2000 WM1 exposure corrected comet image bright pixels removed regions around point sources removed EPIC MOS 1 EPIC pn comet coordinates

51 1/14 C/2000 WM1, 2001 Dec /12 1/10 1/8 1/6 1/4 1/2 of X-ray peak intensity nucleus X-ray peak intensity Sun Sun X-ray contours, kev, XMM / EPIC pn 5 arcmin km Optical image composed of 45 CCD images taken on 2001 Dec 13, 17:38 19:15 UT at the Observatorio Astronomico de Mallorca (OAM) astrometrically calibrated, stars removed

52 XMM-Newton observation of Comet C/2000 WM1 X-ray spectrum

53 XMM-Newton spectra of Comet C/2000 WM1 EPIC - MOS 1

54 XMM-Newton spectra of Comet C/2000 WM1 identification of emission lines in the EPIC spectra EPIC MOS 1

55 Comet C/2000 WM1 XMM / EPIC - MOS 1

56 XMM-Newton observation of Comet C/2000 WM1 spectral evolution across the coma

57 XMM-Newton observation of Comet C/2000 WM1 reconstructed images from spectral fits

58 XMM-Newton observation of Comet C/2000 WM1 reconstructed images from spectral fits O C C O 4+, 5+, 6+, 7+, 2p 3p 1s

59 XMM-Newton / EPIC pn: Suppressing the detector noise E = ev noise E = ev noise

60 X-rays from comets and their impact on physics and astrophysics Astrophysics Planets atmosphere evaporation evolution Comets Solar wind Soft diffuse charge exchange coma heavy ion content X-ray background induced X-ray emission at higher energies gas production rate heliographic latitude geocorona gas to dust ratio chemical composition galactic solar heliosphere center origin of comets velocity emission stellar heliospheres density origin of solar system ionisation local bubble other locations? Physics charge exchange process: cross sections for single and double charge exchange efficiency of X-ray emission transition probabilities multi-electron transitions variability Laboratory physics cosmology Theoretical physics improved plasma diagnostics Calibration of x-ray detectors in space sharp discrete emission lines diffuse source soft X-ray spectrum improved detector calibration ion traps electron cyclotron resonance ion source single-collisionconditions COB: classical over-the barrier model CTMC: classical trajectory Monte Carlo technique LZ: Landau-Zener approximation CC: quantum-mechanical close-coupling method