Initial X-Ray Calorimter Results from a recent Sounding Rocket Flight

A 36-pixel array of microcalorimeters was recently flown to measure high resolution spectra of the diffuse x-ray background between 0.05 - 1.0 keV. The calorimeters consist of ion implanted silicon thermisters each having a HgTe absorber with dimensions of 0.5 mm by 2.0 mm and require an operating temperature of 60 mK. The low operating temperature for the detectors is provided by an adiabatic demagnetization refrigerator. Observation time was approximately 240 seconds and the target for the array was centered on l=90 b=+60 with the field of view mechanically collimated to 1 sr. A preliminary spectum will be presented that shows several lines due to highly ionized elements in the interstellar medium. The ratio of O VII line to O VII line constrains models of the temperature of the x-ray emitting plasma. Upper limits placed on the Fe lines will be discussed.