Smith, Stephen J.Adams, J. S.Bandler, S. R.Betancourt-Martinez, G. L.Miniussi, AntoineSakai, KazuhiroWakeham, Nicholaset al2022-01-202022-01-202016-07-20S. J. Smith, J. S. Adams, S. R. Bandler, G. L. Betancourt-Martinez, J. A. Chervenak, M. P. Chiao, M. E. Eckart, F. M. Finkbeiner, R. L. Kelley, C. A. Kilbourne, A. R. Miniussi, F. S. Porter, J. E. Sadleir, K. Sakai, N. A. Wakeham, E. J. Wassell, W. Yoon, D. A. Bennett, W. B. Doriese, J. W. Fowler, G. C. Hilton, K. M. Morgan, C. G. Pappas, C. N. Reintsema, D. S. Swetz, J. N. Ullom, K. D. Irwin, H. Akamatsu, L. Gottardi, R. den Hartog, B. D. Jackson, J. van der Kuur, D. Barret, P. Peille, "Transition-edge sensor pixel parameter design of the microcalorimeter array for the x-ray integral field unit on Athena," Proc. SPIE 9905, Space Telescopes and Instrumentation 2016: Ultraviolet to Gamma Ray, 99052H (20 July 2016); https://doi.org/10.1117/12.2231749https://doi.org/10.1117/12.2231749http://hdl.handle.net/11603/24031Stephen J. Smith J. S. Adams, S. R. Bandler, G. L. Betancourt-Martinez, J. A. Chervenak, M. P. Chiao, M. E. Eckart, F. M. Finkbeiner, R. L. Kelley, C. A. Kilbourne, Antoine Miniussi, F. S. Porter, J. E. Sadleir, Kazuhiro Sakai, Nicholas Wakeham, E. J. Wassell, W. Yoon, D. A. Bennett, W. B. Doriese, J. W. Fowler, G. C. Hilton, K. M. Morgan, C. G. Pappas, C. N. Reintsema, D. S. Swetz, J. N. Ullom, K. D. Irwin, H. Akamatsu, L. Gottardi, R. den Hartog, B. D. Jackson, J. van der Kuur, D. Barret, P. PeilleThe focal plane of the X-ray integral field unit (X-IFU) for ESA’s Athena X-ray observatory will consist of ~ 4000 transition edge sensor (TES) x-ray microcalorimeters optimized for the energy range of 0.2 to 12 keV. The instrument will provide unprecedented spectral resolution of ~ 2.5 eV at energies of up to 7 keV and will accommodate photon fluxes of 1 mCrab (90 cps) for point source observations. The baseline configuration is a uniform large pixel array (LPA) of 4.28” pixels that is read out using frequency domain multiplexing (FDM). However, an alternative configuration under study incorporates an 18 × 18 small pixel array (SPA) of 2” pixels in the central ~ 36” region. This hybrid array configuration could be designed to accommodate higher fluxes of up to 10 mCrab (900 cps) or alternately for improved spectral performance (< 1.5 eV) at low count-rates. In this paper we report on the TES pixel designs that are being optimized to meet these proposed LPA and SPA configurations. In particular we describe details of how important TES parameters are chosen to meet the specific mission criteria such as energy resolution, count-rate and quantum efficiency, and highlight performance trade-offs between designs. The basis of the pixel parameter selection is discussed in the context of existing TES arrays that are being developed for solar and x-ray astronomy applications. We describe the latest results on DC biased diagnostic arrays as well as large format kilo-pixel arrays and discuss the technical challenges associated with integrating different array types on to a single detector die.20 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