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Application of X-ray plasma diagnostics to nova winds
- 1. XMM-Newton Chandra Application of X-ray Plasma Diagnostics to Nova Winds Jan-Uwe Ness XMM-Newton Science Operations Centre Swift European Space Astronomy Centre (ESAC)
- 2. The RS Oph system Recurrent Nova with 6 recorded outbursts since 1898
- 4. outburst Accreted material: H-rich! Nuclear burning ignites WD
- 5. outburst Accreted material: H-rich! Nuclear burning ignites WD enough radiative energy is produced to drive a wind with v ≈ 1500 km s-1
- 6. Radiatively driven expansion Pseudo Stellar Nuclear Atmosphere burning equivalent to a stellar radiation zone 6 m WD 0 x10 k R=10 ay aft er 1 d Photosphere brightest in optical -> discovery
- 7. Pseudo Stellar Nuclear Atmosphere burning WD Photosphere Density drops, outer layers go optically thin => Radius of Photosphere recedes to inner, hotter, layers
- 8. Pseudo Stellar Nuclear Atmosphere burning WD Photosphere => fades in optical but Lbol constant => spectrum shifts to higher energies ...
- 9. Pseudo Stellar Nuclear Atmosphere burning Super-Soft-Source X-ray spectrum WD ⇒ SSS phase Photosphere .... until the peak of the spectrum reaches soft X-rays --> direct observations of nuclear burning
- 10. Constant Bolometric Luminosity phase Lbol=1038 erg/s WD WD WD optical UV X-ray
- 13. Novae are powered by nuclear burning The pressure is not high enough on a WD surface to produce any elements heavier than Helium The CNO cycle changes the relative abundances of C, N, and O If the nova ejecta show any other anomalies in composition, then either - WD material has been dredged up - The companion is anomalous
- 14. Shock with stellar wind SSS Emission from hot white dwarf + giant in Symbiotic Novae + MS star in Classical Novae
- 15. Swift observations of RS Oph Osborne et al. (2011) shock phase SSS phase nebular phase optical
- 16. Swift observations of RS Oph Osborne et al. (2008) shock phase SSS phase nebular phase XMM-Newton------------ Chandra Chandra Chandra/XMM XMM-Newton Chandra
- 17. Swift spectra
- 18. grating spectra
- 19. RS Oph: 13.8 days after outburst H-like ions He-like ions other lines (FeXVII - FeXXV) simultaneous Chandra and XMM spectra
- 21. Ness & Jordan (2008) MNRAS 385, 1691
- 23. 3-T APEC model reproduces the observations ==> Assumption of collisional equilibrium may not be too bad proper EMD analysis
- 24. f G T
- 25. N Mg S Fe Si O Ne
- 26. f G T
- 27. f G T
- 28. Fe N Ne S Mg Si O
- 29. 0.46 x solar solar abundance
- 31. RS Oph secondary has [N/Fe]=0.9: (Pavlenko et al. 2008) => 20-40% of N from outburst or companion
- 32. Sample of M giants by Smith & Lambert (1985/86) RS Oph secondary has [N/Fe]=0.9: (Pavlenko et al. 2008) => 20-40% of N from outburst or companion
- 33. Sample of M giants by Rich et al. (2007) Mg, Si not produced in outburst => must come from WD or companion
- 34. Summary The companion in Symbiotic Novae is a giant star that has similar abundance ano- malies as those expected in nova ejecta The abundances for RS Oph appear more anomalous than for typical stars of the same spectral type as the companion We might be seeing WD material => too many heavy elements for SN Ia But: The companion in symbiotics is stripped off the outer layers, exposing layers with different abundances.