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Search Publications by: Nathan Ortiz (Fed)

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Displaying 1 - 4 of 4

A tabletop x-ray tomography instrument for nanometer-scale imaging: demonstration of the 1,000-element transition-edge sensor subarray

August 1, 2023
Author(s)
Paul Szypryt, Nathan J. Nakamura, Dan Becker, Douglas Bennett, Amber L. Dagel, W.Bertrand (Randy) Doriese, Joseph Fowler, Johnathon Gard, J. Zachariah Harris, Gene C. Hilton, Jozsef Imrek, Edward S. Jimenez, Kurt W. Larson, Zachary H. Levine, John Mates, Daniel McArthur, Luis Miaja Avila, Kelsey Morgan, Galen O'Neil, Nathan Ortiz, Christine G. Pappas, Dan Schmidt, Kyle R. Thompson, Joel Ullom, Leila R. Vale, Michael Vissers, Christopher Walker, Joel Weber, Abigail Wessels, Jason W. Wheeler, Daniel Swetz
We report on the 1,000-element transition-edge sensor (TES) x-ray spectrometer implementation of the TOMographic Circuit Analysis Tool (TOMCAT). TOMCAT combines a high spatial resolution scanning electron microscope (SEM) with a highly efficient and

Design of a 3000 pixel transition-edge sensor x-ray spectrometer for microcircuit tomography

August 1, 2021
Author(s)
Paul Szypryt, Douglas Bennett, William J. Boone, Amber L. Dagel, G Dalton, William Doriese, Malcolm Durkin, Joseph Fowler, Edward Garboczi, Jonathon D. Gard, Gene Hilton, Jozsef Imrek, E S. Jimenez, Vincent Y. Kotsubo, K Larson, Zachary H. Levine, John Mates, D McArthur, Kelsey Morgan, Nathan J. Nakamura, Galen O'Neil, Nathan Ortiz, Christine G. Pappas, Carl Reintsema, Dan Schmidt, Daniel Swetz, K R. Thompson, Joel Ullom, C Walker, Joel C. Weber, Abigail Wessels, J W. Wheeler
Feature sizes in integrated circuits have decreased substantially over time, and it has become increasingly difficult to three-dimensionally image these complex circuits after fabrication. This can be important for process development, defect analysis, and

Improved plutonium and americium photon branching ratios from microcalorimeter gamma spectroscopy

October 11, 2020
Author(s)
M. D. Yoho, K. E. Koehler, Dan Becker, Douglas Bennett, M. H. Carpenter, M. P. Croce, J. D. Gard, John Mates, D. J. Mercer, Nathan Ortiz, Dan Schmidt, C. M. Smith, Daniel Swetz, A. D. Tollefson, Joel Ullom, Leila R. Vale, Abigail Wessels, D. T. Vo
Photon branching ratios are critical input data for activities such as nuclear materials protection and accounting because they allow material compositions to be extracted from measurements of gamma-ray intensities. Uncertainties in these branching ratios

A Predictive Control Algorithm for Time-Division-Multiplexed Readout of TES Microcalorimeters

January 28, 2020
Author(s)
Malcolm S. Durkin, Galen C. O'Neil, William B. Doriese, Johnathon D. Gard, Gene C. Hilton, Jozsef Imrek, Nathan J. Ortiz, Carl D. Reintsema, Robert W. Stevens, Daniel S. Swetz, Joel N. Ullom
Time division multiplexing (TDM) uses a digital flux-locked loop (DFLL) to linearize each first-stage SQUID amplifier. Presently, the dynamic range of our TDM systems is limited by the use of a proportional-integral controller to maintain the DFLL. In this