Abstract Details

Name: Panini Singam
Affiliation: IIA, Bengaluru
Conference ID: ASI2019_146
Title : A quiet sun imager : Design and science prospects
Authors and Co-Authors : S. Narendranath, P. Sreekumar, K. Sankarasubramanian, Sarthak Choudhary , Ravindra B
Abstract Type : Poster
Abstract Category : Sun and the Solar System
Abstract : The soft X ray spectrum of the Sun has often been approximated to an isothermal plasma emission embedded with emission lines. It is now well known that the flare plasma is multithermal and the emission line strengths varying pointing to the need for soft X ray spectroscopy in the less than 2 keV region. This region in energy has several closely spaced lines at low temperatures which would help us probe the plasma during quiet periods of the Sun. We present a novel design of a solar imager targeting the faint sun regions in soft X rays. This instrument works in two modes: a) a high-resolution imager with parabolic and hyperbolic profiles Wolter type I optics during faint sun phase to observe micro flare formation and to study the pre-flare conditions of the sun. b) During bright solar events (flares brighter than C- class flare), the configuration will be modified to act as a high-resolution spectrometer from (0.5 keV to 6.5 keV) using multilayer mirrors. For the spectrometer, a mosaic multilayer mirror with laterally varied layer thickness is placed at focus at 6^o with respect to the optics axis and detector is placed along the reflected beam at the defocused image plane. As the incident beam of broadband X-rays on multilayer mirror is in a range of angles (due to convergence from the optics), the reflected beam is spectrally separated (by the nature of multilayer mirrors). Since the detector is defocused the spectral separation is correlated to the spatial distribution on the detector which can act as a spectrometer.