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NASA NTRS · 20150018291

Designing the X-Ray Microcalorimeter Spectrometer for Optimal Science Return

Ptak, Andrew·Bandler, Simon R.·Bookbinder, Jay·Kelley, Richard L.·Petre, Robert·Smith, Randall K.·Smith, Stephen
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Abstract

Recent advances in X-ray microcalorimeters enable a wide range of possible focal plane designs for the X-ray Microcalorimeter Spectrometer (XMS) instrument on the future Advanced X-ray Spectroscopic Imaging Observatory (AXSIO) or X-ray Astrophysics Probe (XAP). Small pixel designs (75 microns) oversample a 5-10" PSF by a factor of 3-6 for a 10 m focal length, enabling observations at both high count rates and high energy resolution. Pixel designs utilizing multiple absorbers attached to single transition-edge sensors can extend the focal plane to cover a significantly larger field of view, albeit at a cost in maximum count rate and energy resolution. Optimizing the science return for a given cost and/or complexity is therefore a non-trivial calculation that includes consideration of issues such as the mission science drivers, likely targets, mirror size, and observing efficiency. We present a range of possible designs taking these factors into account and their impacts on the science return of future large effective-area X-ray spectroscopic missions.

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Ptak, Andrew, Bandler, Simon R., Bookbinder, Jay, Kelley, Richard L., Petre, Robert, Smith, Randall K., Smith, Stephen. 2013-09-26. Designing the X-Ray Microcalorimeter Spectrometer for Optimal Science Return. https://ntrs.nasa.gov/citations/20150018291

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