title: A high resolution gamma-ray spectrometer based on superconducting microcalorimeters.
abstract: Improvements in superconductor device fabrication, detector hybridization techniques, and superconducting quantum interference device readout have made square-centimeter-sized arrays of gamma-ray microcalorimeters, based on transition-edge sensors (TESs), possible. At these collecting areas, gamma microcalorimeters can utilize their unprecedented energy resolution to perform spectroscopy in a number of applications that are limited by closely-spaced spectral peaks, for example, the nondestructive analysis of nuclear materials. We have built a 256 pixel spectrometer with an average full-width-at-half-maximum energy resolution of 53 eV at 97 keV, a useable dynamic range above 400 keV, and a collecting area of 5 cm(2). We have demonstrated multiplexed readout of the full 256 pixel array with 236 of the pixels (91%) giving spectroscopic data. This is the largest multiplexed array of TES microcalorimeters to date. This paper will review the spectrometer, highlighting the instrument design, detector fabrication, readout, operation of the instrument, and data processing. Further, we describe the characterization and performance of the newest 256 pixel array.
authors.affiliation: National Institute of Standards and Technology, Boulder, Colorado 80305, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Bennett
authors.forename: R D
authors.initials: RD
authors.lastname: Horansky
authors.forename: D R
authors.initials: DR
authors.lastname: Schmidt
authors.forename: A S
authors.initials: AS
authors.lastname: Hoover
authors.forename: R
authors.initials: R
authors.lastname: Winkler
authors.forename: B K
authors.initials: BK
authors.lastname: Alpert
authors.forename: J A
authors.initials: JA
authors.lastname: Beall
authors.forename: W B
authors.initials: WB
authors.lastname: Doriese
authors.forename: J W
authors.initials: JW
authors.lastname: Fowler
authors.forename: C P
authors.initials: CP
authors.lastname: Fitzgerald
authors.forename: G C
authors.initials: GC
authors.lastname: Hilton
authors.forename: K D
authors.initials: KD
authors.lastname: Irwin
authors.forename: V
authors.initials: V
authors.lastname: Kotsubo
authors.forename: J A B
authors.initials: JA
authors.lastname: Mates
authors.forename: G C
authors.initials: GC
authors.lastname: O'Neil
authors.forename: M W
authors.initials: MW
authors.lastname: Rabin
authors.forename: C D
authors.initials: CD
authors.lastname: Reintsema
authors.forename: F J
authors.initials: FJ
authors.lastname: Schima
authors.forename: D S
authors.initials: DS
authors.lastname: Swetz
authors.forename: L R
authors.initials: LR
authors.lastname: Vale
authors.forename: J N
authors.initials: JN
authors.lastname: Ullom