X-ray Flare Spectra from the DIOGENESS Spectrometer and its concept applied to ChemiX on the Interhelioprobe spacecraft

The {em DIOGENESS} X-ray crystal spectrometer on the {em CORONAS-F} spacecraft operated for a single month (25~August to 17~September) in 2001 but in its short lifetime obtained one hundred and forty high-resolution spectra from some eight solar flares with {em GOES} importance ranging from C9 to X5. The instrument included four scanning flat crystals with wavelength ranges covering the regions of sixiii (6.65~AA), sxv (5.04~AA), and caxix (3.18~AA) X-ray lines and associated dielectronic satellites. Two crystals covering the caxix lines were oriented in a ``Dopplerometer manner, i.e. such that spatial and spectral displacements both of which commonly occur in flares can be separated. We describe the {em DIOGENESS} spectrometer and the spectra obtained during flares which include lines not hitherto seen from spacecraft instruments. An instrument with very similar concept is presently being built for the two Russian {em Interhelioprobe} spacecraft due for launch in 2020 and 2022 that will make a near-encounter (perihelion $sim 0.3$ a.u.) to the Sun in its orbit. We outline the results that are likely to be obtained.