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NLTE Model Atmospheres for Super-Soft X- ray Sources

NLTE Model Atmospheres for Super-Soft X- ray Sources. Thomas Rauch, Klaus Werner and the GAVO and AstroGrid-D Teams. Spectral Energy Distributions for Hot Stars. The nebular information indicates that the spectrum of the star deviates considerably from a blackbody . Author in 2008!.

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NLTE Model Atmospheres for Super-Soft X- ray Sources

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  1. NLTE Model Atmospheresfor Super-Soft X-raySources Thomas Rauch, Klaus Werner and the GAVO and AstroGrid-D Teams

  2. Spectral Energy Distributions for Hot Stars The nebularinformationindicatesthatthespectrumofthestardeviatesconsiderablyfrom a blackbody. Author in 2008!

  3. they still use black bodies to simulate ionizing fluxes of hot stars … Rauch

  4. NLTE Model Atmospheres C IV doublet “optical” RBB 5  6, 6  8 C III singlet + triplet all stars with spectral type B or earlier regarded as a domain of specialists high computational times atomic data

  5. More Model Atoms … simplified Hauschildt diagram

  6. and a very old gag ... simplified Hauschildt diagram

  7. GAVO II Project • provide access to SEDs at three levels: • fast and easy • unexperienced user, no detailed knowledge about the model-atmosphere code necessary • individual • interested user, detailed analysis of special objects • experienced • define own model atoms, comparison of codes, etc.

  8. VO Service TheoSSA • based on the Tübingen NLTE Model Atmosphere Package TMAP, the GAVO Service TheoSSA provides • Spectral Energy Distributions (SEDs) • TheoSSA (http://vo.ari.uni-heidelberg.de/ssatr-0.01/TrSpectra.jsp?) • Simulation Software • TMAW (http://astro.uni-tuebingen.de/~TMAW/TMAW.shtml) • Atomic Data • TMAD (http://astro.uni-tuebingen.de/~rauch/TMAD/TMAD.html)

  9. Way to Reality in the 21st Century • use SED grids • ready to use, interpolation • calculate individual model atmospheres • Teff, log g, mass fraction {Xi}, i  (H, He, C, N, O) • standard model atoms • create own atomic-data files, i  (H - Ni), and calculate model atmospheres and SEDs

  10. TheoSSA

  11. Calculationof SEDs • cpu time increases with number of considered elements • 1 H+He+C+N+O model ≈1 day on a fast PC • IAAT cluster: 4 models parallel • calculation of SED grids • compute resources of AstroGrid-D

  12. Why use a Grid? • scales according to demand • 1, 10, or 100 cores available at any time • higher reliability • middleware offers additional options • job monitoring, statistics, error handling • TMAP is easy to compute • no interprocess-communication • no complex compilation, all libraries present

  13. Spectroscopy of LS V +46°21 • exciting star of Sh 2-216 • closest PN known, d = 130pc • apparent diameter 1.6° • LS V +46°21 about 0.2 radii off centre • mild interaction with ISM • thin disk orbit of low inclination and eccentricity • Kerber et al. 2004 • FUSE: 67.6 ksec in 2003/2004, R 0.05 Å • STIS: 5.5 ksec in 2000, R 0.06 Å Hα + [O III] Dean Salman www.deansalman.com

  14. Spectroscopy of LS V +46°21 • HHeCNOFMgSiPSAr + CaScTiVCrMnFeCoNi • IrOnIc • Rauch & Deetjen 2003 • 686 NLTE levels • 2417 individual lines • 9 million iron-group lines • Kurucz 1996 • Rauch et al. 2007, A&A, 470, 317 Teff= 95 000 K log g = 6.9

  15. LS V +46°21 Photospheric abundances exhibit interplay of gravitational settling and radiative levitation Photospheric abundances in agreement with diffusion predictions (Chayer et al. 1995)

  16. H1504+65 Teff = 200 000 K log g = 8

  17. Magnesium in H 1504+65

  18. H 1504+65: CHANDRA Spectrum Werner et al. 2004

  19. H 1504+65: Iron group

  20. Nova V 4743 Sgr • outburst Sep 20, 2002, mV = 5 • Mar 2003: brightest super-soft source in the sky • CHANDRA spectrum • C V, C VI, N VI, N VII, O VII absorptions • Teff 1 – 2 MK (Ness et al. 2003) • XMM-RGS spectrum (Apr 4, 2003) • Teff 610 kK (Rauch, Werner & Orio 2005)

  21. SEDs for Extremely Hot Stars

  22. V 4743 Sgr

  23. Teff Determination: N VI / N VII IonizationEquilibrium

  24. Effective Temperature of Nova V 4743 Sgr after Burst

  25. EXO 0748-676 (LMXB) • discovery of gravitationally redshifted photosphericabsorption lines of Fe XXV, Fe XXVI, O VIII in burst spectra • Cottam, Paerels & Mendez 2002 • letter to NATURE, 420, p. 51

  26. no fit at z = 0.35

  27. much better fit at z = 0.24 ? • Details see Poster by Suleimanov et al. and Rauch et al. 2008

  28. If carried out with sufficient care, theory works. D. Mihalas Never believe an observation, until you have a theory to prove it. L. Auer

  29. VO Service TheoSSA • Spectral Energy Distributions (SEDs) • TheoSSA (http://vo.ari.uni-heidelberg.de/ssatr-0.01/TrSpectra.jsp?) • Simulation Software • TMAW (http://astro.uni-tuebingen.de/~TMAW/TMAW.shtml) • Atomic Data • TMAD (http://astro.uni-tuebingen.de/~rauch/TMAD/TMAD.html)

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