F. Scott Porter NASA / Goddard Space Flight Center Daniel Schwartz Smithsoninan Astrophysical Observatory

Technology Development: Further developments of large-format, high-resolution, low-temperature, x-ray detectors will enable dramatic advances for the future of X-ray astronomy through missions such as Generation-X (Gen-X). In this paper we discuss the state of the art in these detectors, reviewing five different sensor technologies, and discuss which have the most potential of producing arrays of greater than one million pixels, 0.1 arcsecond angular scale, while giving an energy resolution of less than 2 eV in the 0.2-10 keV band. We conclude that transition edge sensor (TES) and metallic magnetic calorimeter (MMC) based microcalorimeters hold the most potential for meeting the requirements of mission concepts such as Generation-X, while microwave kinetic inductance detectors (MKIDs) hold potential for large format arrays, although this technology currently appears better matched to spectroscopy below 1 keV. As well as the further development of these sensor technologies, we also strongly recommend a research and development program to pursue multiplexing schemes utilizing microwave read-out that can be adapted to read out any of the leading candidate technologies of the future. When combined with position-sensitive detector versions of the leading sensor technologies, mega-pixel arrays can become a reality by the end of this decade. We describe the Generation-X roadmap for th