Analysis of an Active Region EUV Spectrum from SERTS-97
Abstract
Goddard Space Flight Center's Solar EUV Research Telescope and Spectrograph (SERTS) was flown on 1997 November 18, carrying a CCD-intensified detector and a multilayer-coated toroidal diffraction grating that enhanced the sensitivity over that of a standard gold-coated grating throughout the instrument's first-order waveband (299 -- 353 Angstroms). Spectra and spectroheliograms of NOAA active region 8108 (N21 E18) were obtained with a spectral resolution (instrumental FWHM) ~ 118 m Angstroms. Spectra and spectroheliograms of quiet areas southeast of the active region were also obtained. An end-to-end radiometric calibration of the rocket instrument was carried out at Rutherford-Appleton Laboratory in the same facility used to calibrate the Coronal Diagnostic Spectrometer (CDS) on the Solar and Heliospheric Observatory (SOHO) satellite, using the same EUV light source. The accuracy of this calibration is confirmed by the excellent agreement between measured and theoretical values of density- and temperature-insensitive line intensity ratios among some of the nearly 100 spectral lines observed in the spatially averaged active region spectrum. We present the spectrum itself, and discuss measurements of the plasma density, non-thermal mass motions, relative wavelength shifts, and the differential emission measure. This work is supported by NASA through RTOP grants and contract NAS5-99145.
- Publication:
-
AAS/Solar Physics Division Meeting #31
- Pub Date:
- May 2000
- Bibcode:
- 2000SPD....31.0214B