Smith, Stephen J.Adams, Joseph S.Bandler, Simon R.Chervenak, James A.Datesman, Aaron M.Eckart, Megan E.Finkbeiner, Fred M.Hummatov, RuslanKelley, Richard L.Kilbourne, Caroline A.Miniussi, AntoinePorter, Frederick S.Sadleir, John E.Sakai, KazuhiroWakeham, NicholasWassell, Edward J.2022-01-202022-01-202019-04-08Stephen J. Smith, Joseph S. Adams, Simon R. Bandler, James A. Chervenak, Aaron M. Datesman, Megan E. Eckart, Fred M. Finkbeiner, Ruslan Hummatov, Richard L. Kelley, Caroline A. Kilbourne, Antoine R. Miniussi, Frederick S. Porter, John E. Sadleir, Kazuhiro Sakai, Nicholas A. Wakeham, Edward J. Wassell, "Multiabsorber transition-edge sensors for x-ray astronomy," J. Astron. Telesc. Instrum. Syst. 5(2) 021008 (8 April 2019) https://doi.org/10.1117/1.JATIS.5.2.021008https://doi.org/10.1117/1.JATIS.5.2.021008http://hdl.handle.net/11603/24030We are developing arrays of position-sensitive microcalorimeters for future x-ray astronomy appli cations. These position-sensitive devices commonly referred to as hydras consist of multiple x-ray absorbers, each with a different thermal coupling to a single-transition-edge sensor microcalorimeter. Their development is motivated by a desire to achieve very large pixel arrays with some modest compromise in performance. We report on the design, optimization, and first results from devices with small pitch pixels (<75 μm) being developed for a high-angular and energy resolution imaging spectrometer for Lynx. The Lynx x-ray space telescope is a flagship mission concept under study for the National Academy of Science 2020 decadal survey. Broadband full-width-half-maximum (FWHM) resolution measurements on a 9-pixel hydra have demonstrated ΔEFWHM ¼ 2.23 0.14 eV at Al-Kα, ΔEFWHM ¼ 2.44 0.29 eV at Mn-Kα, and ΔEFWHM ¼ 3.39 0.23 eV at Cu-Kα. Position discrimination is demonstrated to energies below <1 keV and the device performance is well-described by a finite-element model. Results from a prototype 20-pixel hydra with absorbers on a 50-μm pitch have shown ΔEFWHM ¼ 3.38 0.20 eV at Cr-Kα1. We are now optimizing designs specifically for Lynx and extending the number of absorbers up to 25/hydra. Numerical simulation suggests optimized designs could achieve ∼3 eV while being compatible with the bandwidth requirements of the state-of-the art multiplexed readout schemes, thus making a 100,000 pixel microcalorimeter instrument a realistic goal.12 pagesen-USThis work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.Public Domain Mark 1.0http://creativecommons.org/publicdomain/mark/1.0/Text