1 / 22

Fe L-shell Diagnostics in Theory and Practice

Fe L-shell Diagnostics in Theory and Practice. Christopher Mauche Duane Liedahl Kevin Fournier Physics & Advanced Technologies Lawrence Livermore National Laboratory. X-ray Diagnostics of Astrophysical Plasmas  Cambridge, MA  2004 Nov 15–17. cool supersonic accretion flow.

apu
Download Presentation

Fe L-shell Diagnostics in Theory and Practice

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. Fe L-shell Diagnostics in Theory and Practice Christopher Mauche Duane Liedahl Kevin Fournier Physics & Advanced Technologies Lawrence Livermore National Laboratory X-ray Diagnostics of Astrophysical Plasmas  Cambridge, MA  2004 Nov 15–17

  2. cool supersonic accretion flow Magnetic field line Magnetic field line B = 0.1–100 MG Hard X-rays (Bremsstrahlung) T = 1–100 MK SHOCK Stream of slow shock-heated matter Infrared – Optical – UV (cyclotron radiation) Soft X-rays – UV (blackbody radiation) T = 300 kK White Dwarf Photosphere T = 20 kK Accretion Geometry of Magnetic Cataclysmic Variables • Density enhanced by: • Magnetic channeling • Shock compression • Settling of the plasma Figure courtesy of Vadim Burwitz

  3. Ne IX || | 21 | 22 | 20 | 22 | 17 | 17 || 17 | 17 | Comparison of HR 1099 and EX Hya EX Hya is missing lines of: Fe XVII17.10, Fe XX, Fe XXI, & has an inverted Fe XXII11.92/ 11.77 ratio.

  4. H- and He-like lines of EX Hya All the He-like f lines are missing in EX Hya.

  5. He-like R = z/(x+y) = f/i line ratios as a functionof density for (a) Tbb=0 and (b) Tbb=30 kK (b) (a) Apparent absence of He-like f lines in EX Hya could be due to photoexcitation. Mauche (2002, in Physics of CVs and Related Objects)

  6. Fe L-shell spectra were calculated with the Livermore X-ray Spectral Synthesizer (LXSS), a suite of IDL codes that calculates spectral models as a function of temperature and density using HULLAC atomic data. The following spectra are based on models with: Ion levels radrate colrate Fe XXIV 764,1001,704 Fe XXIII 116 8,798 6,478 Fe XXII 228 37,300 24,084 Fe XXI 591 227,743 153,953 Fe XX 609257,765165,350 Fe XIX 605 240,948 164,496 Fe XVIII 456 141,229 93,583 Fe XVII 281 49,882 33,887

  7. Fe XVII Red: 1010 cm3 Blue: 1018 cm3  

  8. Fe XVIII Red: 1010 cm3 Blue: 1018 cm3

  9. Fe XIX Red: 1010 cm3 Blue: 1018 cm3

  10. Fe XX Red: 1010 cm3 Blue: 1018 cm3 

  11. Fe XXI Red: 1010 cm3 Blue: 1018 cm3 

  12. Fe XXII Red: 1010 cm3 Blue: 1018 cm3  

  13. Fe XXIII Red: 1010 cm3 Blue: 1018 cm3

  14. Fe XXIV Red: 1010 cm3 Blue: 1018 cm3

  15. Fe XVII spectrum of EX Hya Mauche, Liedahl, & Fournier (2001, ApJ, 560, 992)

  16. Level population processes in Fe XVII

  17. Fe XVII17.10/17.05 line ratio as a functionof density for Te=4 MK and Tbb=20…60 kK ne > 3E14 cm3 or Tbb > 55 kK

  18. 23 | 22 | 22 | Fe XXII spectrum of EX Hya Mauche, Liedahl, & Fournier (2003, ApJ, 588, L101)

  19. Dominant collisional and radiative channels of Fe XXII 1011 cm3 1017 cm3

  20. Fe XXII11.92/11.77 line ratio as a function of density for Te=12.8 MK and Tbb=0, 60, 80, and 100 kK This calculation includes the relativistic R-matrix electron excitation rate coefficients of Zhang & Pradhan (1997) and the protonexcitation rate coefficients of Foster, Keenan, & Reid (1997). ne ~ 0.3–3E14 cm3 (1) or Tbb > 100 kK (3)

  21. Summary: • There are a number of potential Fe L-shell density diagnostics in addition to the Fe XVII17.10/17.05 and Fe XXII11.92/ 11.72 ratios, although the others are fairly subtle (e.g., bright lines simply disappear [Fe XX& Fe XXI], lines are blended [Fe XXIII & Fe XXI], etc.). • Application of these diagnostics requires sources with fairly high densities and spectra with good signal-to-noise ratio; higher spectral resolution would help. • Fe L-shell spectrum of EX Hya is fully consistent with that of a high-density (ne ~ 1014 cm3) multi-temperature plasma.

  22. This work was performed under the auspices of the US Department of Energy by the University of California Lawrence Livermore National Laboratory under contract W-7405-Eng-48.

More Related