Abstract
We present the △n = 0 (n = 3 to n = 3) EUV spectra of M-shell iron ions from a tokamak plasma obtained during the "ramp-down" phase of the discharge. The fractional ion abundances for K-like Fe+7 to Si-like Fe+12 are found from fitting model spectra to the measured spectrum. The plasma temperature is measured as a function of position by Thomson scattering of laser light and Langmuir probes. Collisional-radiative simulations have been computed for the above ions, using atomic data generated with the HULLAC suite of codes. The blended M-shell spectrum is strongly sensitive to temperature; this makes it a potentially useful diagnostic for observations of stellar coronae where the differential emission measure is dominated by temperatures around 1 MK.
Original language | English |
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Pages (from-to) | L117-L120 |
Journal | Astrophysical Journal |
Volume | 550 |
Issue number | 1 PART 2 |
DOIs | |
State | Published - 20 Mar 2001 |
Keywords
- Atomic data
- Methods: laboratory
- Stars: coronae
- Ultraviolet: stars