  Previous estimates of the solar flare abundances of Si, S, Cl, Ar, and K from
the RESIK X-ray crystal spectrometer on board the CORONAS-F spacecraft were
made on the assumption of isothermal X-ray emission. We investigate the effect
on these estimates by relaxing this assumption and instead determining the
differential emission measure (DEM) or thermal structure of the emitting plasma
by re-analyzing RESIK data for a GOES class M1.0 flare on 2002 November~14
(SOL2002-11-14T22:26) for which there was good data coverage. The analysis
method uses a maximum-likelihood (Withbroe--Sylwester) routine for evaluating
the DEM. In a first step, called here AbuOpt, an optimized set of abundances of
Si, S, Ar, and K is found that is consistent with the observed spectra. With
these abundances, the differential emission measure evolution during the flare
is found. The abundance optimization leads to revised abundances of silicon and
sulfur in the flare plasma: $A({\rm S}) = 6.94 \pm 0.06$ and $A({\rm Si}) =
7.56 \pm 0.08$ (on a logarithmic scale with $A({\rm H}) = 12$). Previously
determined abundances of Ar, K, and Cl from an isothermal assumption are still
the preferred values. During the flare's maximum phase, the X-ray-emitting
plasma has a basically two-temperature structure, with the cooler plasma with
approximately constant temperature (3--6~MK) and a hotter plasma with
temperature $16-21$~MK. Using imaging data from the RHESSI hard X-ray
spacecraft, the emission volume of the hot plasma is deduced from which lower
limits of the electron density $N_e$ and the thermal content of the plasma are
given.
