Multitemperature analysis of solar X-ray line emission

Abstract

In this paper we propose and test a new method of multitemperature analysis of solar X-ray spectra. The method, which is based on a technique developed by Withbroe (1975), is designed to be used in the interpretation of spectra, to be measured by the X-Ray Polychromator on the Solar Maximum Mission. Various tests of the method on simulated temperature models establish its usefulness, generality, and stability. The possibilities of deriving the relative element abundances are analysed. The results of the present paper extend the possibility of the multitemperature analysis of X-ray spectra as compared with the results of Craig and Brown (1976a, b) and Craig (1977).

Diagnostic of the temperature and differential emission measure (DEM) based on <I>Hinode</I>/XRT data

“…In our calculations we started from a constant value DEM approximation. For detailed descriptions of this method, see Withbroe (1975) and Sylwester et al (1980). Using the WS method we performed 200 simulations consisting of 3000 iterations each.…”

“…In the case of multi-temperature plasma the filter ratio method derives the line-of-sight average isothermal temperature and emission measure. Therefore, in this approach it is more adequate to use many filters or lines in terms of differential emission measure distributions DEM(T )/dT (Pottash et al, 1964;Sylwester et al, 1980). Extended discussion of the DEM versus isothermal approximation can by found, for example, in Schmelz et al (2001), Cirtain et al (2007) and references therein.…”

Analysis of a Series of Solar Flare X-Ray Spectra.

“…The differential emission measure was computed with the iterative procedure of Sylwester, Schrijver, and Mewe (1980). In addition to the collision strengths discussed above, we used ionization equilibrium calculations by Jacobs et al (1977Jacobs et al ( , 1978 Figure 4 illustrates the uncertainty in c(T) for one of the spectra.…”

“…We have plotted the range of (T) values, basing the estimated error on the "continuous" error case of Sylwester, Schrijver and Mewe (1980). factor fc" The integrated emission measures are given in Table 2.…”

First Determinations of Differential Emission Measure Distribution from RESIK X-ray Spectra

“…With known DEM shape it is possible to derive and study in detail flaring plasma composition and energy balance. For calculations of the DEM shape we use Withbroe-Sylwester multiplicative algorithm (Sylwester, Schrijver and Mewe, 1980).…”