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Search Publications by: Johnathon Gard (Assoc)

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Displaying 1 - 25 of 30

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

Proof-of-Principle Experiment for Testing Strong-Field Quantum Electrodynamics with Exotic Atoms: High Precision X-Ray Spectroscopy of Muonic Neon

April 27, 2023
Author(s)
Douglas Bennett, W.Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Johnathon Gard, Gene C. Hilton, Kelsey Morgan, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Takuma Okumura
To test the bound-state quantum electrodynamics (BSQED), we have performed high precision x- ray spectroscopy of the 5g→4f and 5f→4d transitions (BSQED contribution of 2.4 eV and 5.2 eV, respectively) of muonic neons in the low-pressure gas phase under the

Symmetric time-division-multiplexed SQUID readout with two-layer switches for future TES observatories

April 4, 2023
Author(s)
Malcolm Durkin, Scott Backhaus, Simon Bandler, James Chervenak, Ed Denison, W.Bertrand (Randy) Doriese, Johnathon Gard, Gene C. Hilton, Richard Lew, Tammy Lucas, Carl D. Reintsema, Dan Schmidt, Stephen Smith, Joel Ullom, Leila R. Vale, Michael Vissers, Nicholas Wakeham
Time-division multiplexing (TDM) of transition-edge-sensor (TES) microcalorimeters is being developed as the readout tech-nology for the Athena X-ray integral field unit (X-IFU) and is under consideration for future TES-bolometer missions like CMB-S4. We

Measurements of Strong-Interaction Effects in Kaonic-Helium Isotopes at sub-eV Precision with x-ray microcalorimeters

March 18, 2022
Author(s)
Tadashi Hashimoto, S Aikawa, T. Akaishi, M Bazzi, Douglas Bennett, M Berger, D Bosnar, A. D. Butt, C. Curceanu, W.Bertrand (Randy) Doriese, Malcolm Durkin, Y Ezoe, Joseph Fowler, H. Fujioka, Johnathon Gard, C Guaraldo, F.P. Gustafsson, C. Han, R Hayakawa, R. S. Hayano, T Hayashi, J. Hays-Wehle, Gene C. Hilton, T Hiraiwa, M Hiromoto, Y Ichinoge, M Iio, Y Iizawa, M Iliescu, S Ishimoto, Y Ishisaki, K Itahashi, M Iwasaki, Y Ma, T Murakami, T Nishi, H Noda, K Nomura, H Noumi, K Ooi, H Outa, K Piscicchia, Carl D. Reintsema, Y Sada, S Okada, Galen O'Neil, Dan Schmidt, Daniel Swetz, Joel Ullom, S Yamada, J Uhlig
We have measured the 3 d→ 2 p transition x rays of kaonic He 3 and He 4 atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4 (stat)±0.2 (syst) eV

De-excitation dynamics of muonic atoms revealed by high precision spectroscopy of electronic K x rays using a superconducting transition-edge sensor microcalorimeter

July 27, 2021
Author(s)
Douglas Bennett, W.Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Johnathon Gard, Gene C. Hilton, Kelsey Morgan, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Toshiyuki Azuma, Pietro Caradonna, I-Huan Chiu, Tadashi Hashimoto, Ryota Hayakawa, Yuto Ichinohe, Paul Indelicato, TadaAki Isobe, Sohtaro Kanda, Daiji Kato, Miho Katsuragawa, Naritoshi Kawamura, Yasushi Kino, Kenya Kubo, Kairi Mine, Yasuhiro Miyake, Kazuhiko Ninomiya, Hirofumi Noda, Shinji Okada, Takuma Okumura, Kenichi Okutsu, Takahito Osawa, Nancy Paul, Kouichiro Shimomura, Patrick Strasser, Hirotaka Suda, Tadayuki Takahashi, Shinichiro Takeda, Soshi Takeshita, Motonobu Tampo, Hideyuki Tatsuno, XiaoMin Tong, Yasuhiro Ueno, Shin Watanabe, Shinya Yamada
We observed electronic K x rays emitted from muonic iron atoms using a superconducting transition-edge-type sensor microcalorimeter. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic

A Model for Excess Johnson Noise in Superconducting Transition-edge Sensors

May 18, 2021
Author(s)
Abigail Wessels, Kelsey Morgan, Dan Becker, Johnathon Gard, Gene C. Hilton, John Mates, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Leila R. Vale, Douglas Bennett
Transition-Edge Sensors (TESs) are two-dimensional superconducting films used to detect energy or power. These detectors are voltage biased in the superconducting transition where the film resistance is both finite and a strong function of temperature

Mitigating finite bandwidth effects in time-division- multiplexed SQUID readout of TES arrays

March 11, 2021
Author(s)
Malcolm Durkin, Joseph S. Adams, Simon Bandler, James A. Chervenak, Ed Denison, W.Bertrand (Randy) Doriese, Shannon Duff, Fred M. Finkbeiner, Joseph Fowler, Johnathon Gard, Gene C. Hilton, Ruslan Hummatov, Kent Irwin, Young I. Joe, Richard L. Kelley, Caroline A. Kilbourne, Antoine R. Miniussi, Kelsey Morgan, Galen O'Neil, Christine Pappas, Frederick S. Porter, Carl D. Reintsema, Kazuhiro Sakai, Stephen J. Smith, Robert W. Stevens, Daniel Swetz, Paul Szypryt, Joel Ullom, Leila R. Vale, Nicholas A. Wakeham
Time division multiplexing (TDM) is being developed as the readout technology of the X-ray integral field unit (X-IFU), a 3,168-pixel X-ray transition-edge sensor (TES) imaging spectrometer that is part of the European Space Agency's Athena satellite

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

A transition-edge sensor-based x-ray spectrometer for the study of highly charged ions at the National Institute of Standards and Technology electron beam ion trap

December 16, 2019
Author(s)
Paul Szypryt, Galen C. O'Neil, Endre Takacs, Joseph N. Tan, Sean W. Buechele, Aung Naing, Douglas A. Bennett, William B. Doriese, Malcolm S. Durkin, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kelsey M. Morgan, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom, Yuri Ralchenko
We report on the design, commissioning, and initial measurements of a Transition-Edge Sensor (TES) x-ray spectrometer for the Electron Beam Ion Trap (EBIT) at the National Institute of Standards and Technology (NIST). Over the past few decades, the NIST

On Low-Energy Tail Distortions in the Detector Response Function of X-Ray Microcalorimeter Spectrometers

November 21, 2019
Author(s)
Galen C. O'Neil, Paul Szypryt, Endre Takacs, Joseph N. Tan, Sean W. Buechele, Aung Naing, Young I. Joe, Daniel S. Swetz, Daniel R. Schmidt, William B. Doriese, Johnathon D. Gard, Carl D. Reintsema, Joel N. Ullom, John S. Villarrubia, Yuri Ralchenko
We use narrow spectral lines from the X-ray spectra of various highly charged ions to measure low-energy tail-like deviations from a Gaussian response function in a microcalorimeter X-ray spectrometer with Au absorbers at energies from 650 to 3320 eV. We

Crosstalk in microwave SQUID multiplexers

November 15, 2019
Author(s)
John A. Mates, Daniel T. Becker, Douglas A. Bennett, Bradley J. Dober, Johnathon D. Gard, Gene C. Hilton, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom
Low-temperature detector technologies provide extraordinary sensitivity for applications ranging from precision measurements of the cosmic microwave background to high-resolution, high-rate x-ray, and c-ray spectroscopy. To utilize this sensitivity, new

Expanding the Capability of Microwave Multiplexed Readout for Fast Signals in Microcalorimeters

November 11, 2019
Author(s)
Kelsey M. Morgan, Daniel T. Becker, Douglas A. Bennett, Johnathon D. Gard, Jozsef Imrek, John A. Mates, Christine G. Pappas, Carl D. Reintsema, Daniel R. Schmidt, Joel N. Ullom, Joel C. Weber, Abigail L. Wessels, Daniel S. Swetz
Microwave SQUID multiplexing has become a key technology for reading out large arrays of X-ray and gamma-ray microcalorimeters with mux factors of 100 or more. The desire for fast X-ray pulses that accommodate photon counting rates of hundreds or thousands

Soft X-ray spectroscopy with transition-edge sensors at Stanford Synchrotron Radiation Lightsource beamline 10-1

November 5, 2019
Author(s)
Sang-Jun Lee, Charles Titus, Roberto A. Mori, Michael Baker, Douglas Bennett, Hsiao-Mei Cho, W.Bertrand (Randy) Doriese, Joseph Fowler, Kelly J. Gaffney, Allesandro Gallo, Johnathon Gard, Gene C. Hilton, Hoyoung Jang, Young I. Joe, Christopher Kenney, Jason Knight, Thomas Kroll, Jun-Sik Lee, Dale Li, Donhui Lu, Ronald Marks, Michael Minitti, Kelsey Morgan, Ogasawara Hirohito, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Dimosthenis Sokaras, Joel Ullom, Tsu-Chien Weng, Christopher Williams, Betty A. Young, Daniel Swetz, Kent D. Irwin, Dennis Nordlund
We present results obtained with a new soft X-ray spectrometer based on transition-edge sensors (TESs) composed of Mo/Cu bilayers coupled to bismuth absorbers. This spectrometer simultaneously provides excellent energy resolution, high detection efficiency

Microwave SQUID multiplexing for the Lynx x-ray microcalorimeter

March 22, 2019
Author(s)
Douglas A. Bennett, John A. Mates, Simon R. Bandler, Daniel T. Becker, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, K D. Irwin, Kelsey M. Morgan, Carl D. Reintsema, Kazuhiro Sakai, Daniel R. Schmidt, Stephen J. Smith, Daniel S. Swetz, Joel N. Ullom, Leila R. Vale, Abigail L. Wessels
The Lynx x-ray microcalorimeter (LXM) is an imaging spectrometer for the Lynx satellite mission, an x-ray telescope being considered by NASA to be a new flagship mission. Lynx will enable unique astrophysical observations into the x-ray universe due to its

Demonstration of Athena X-IFU Compatible 40-Row Time-Division-Multiplexed Readout

March 19, 2019
Author(s)
Malcolm S. Durkin, Joseph S. Adams, Simon R. Bandler, James A. Chervenak, Saptarshi Chaudhuri, Carl S. Dawson, Edward V. Denison, William B. Doriese, Shannon M. Duff, F. M. Finkbeiner, C. T. FitzGerald, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kent D. Irwin, Young I. Joe, R. L. Kelley, Caroline A. Kilbourne, A. R. Miniussi, Kelsey M. Morgan, Galen C. O'Neil, Christine G. Pappas, F. S. Porter, Carl D. Reintsema, David A. Rudman, Kazuhiro Sakai, Stephen J. Smith, Robert W. Stevens, Daniel S. Swetz, Paul Szypryt, Joel N. Ullom, Leila R. Vale, N. Wakeham, Joel C. Weber, B. A. Young
Time-division multiplexing (TDM) is the backup readout technology for the X-ray Integral Field Unit (X-IFU), a 3168-pixel X-ray transition-edge sensor (TES) array that will provide imaging spectroscopy for european space agency's Athena satellite mission

Optimization of Time-and Code-Division-Multiplexed Readout for Athena X-IFU

March 18, 2019
Author(s)
William B. Doriese, Simon R. Bandler, Saptarshi Chaudhuri, Carl S. Dawson, Edward V. Denison, Shannon M. Duff, Malcolm S. Durkin, C. T. FitzGerald, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kent D. Irwin, Young I. Joe, Kelsey M. Morgan, Galen C. O'Neil, Christine G. Pappas, Carl D. Reintsema, David A. Rudman, Stephen J. Smith, Robert W. Stevens, Daniel S. Swetz, Paul Szypryt, Joel N. Ullom, Leila R. Vale, Joel C. Weber, B. A. Young
Readout of a large, spacecraft-based array of superconducting transition-edge sensors (TESs) requires careful management of the layout area and power dissipation of the cryogenic-circuit components. We present three optimizations of our time- (TDM) and

High-Throughput, DC-Parametric Evaluation of Flux-Activated-Switch-Based TDM and CDM SQUID Multiplexers

March 12, 2019
Author(s)
Carl D. Reintsema, Douglas A. Bennett, Edward V. Denison, Malcolm S. Durkin, William B. Doriese, Joseph W. Fowler, Johnathon D. Gard, Arpi L. Grigorian, Gene C. Hilton, Johannes Hubmayr, Galen C. O'Neil, John A. Mates, Kelsey M. Morgan, Daniel R. Schmidt, Robert W. Stevens, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom, Kent D. Irwin, Saptarshi Chaudhuri, Charles J. Titus, Carl S. Dawson
The successful realization and broad deployment of transition edge sensor (TES)-based detector systems has led to significant demand for time-division and code-division superconducting quantum interference device (SQUID) multiplexers time division

Use of Transition Models to Design High Performance TESs for the LCLS-II Soft X-Ray Spectrometer

March 4, 2019
Author(s)
Kelsey M. Morgan, Daniel T. Becker, Douglas A. Bennett, William B. Doriese, Johnathon D. Gard, K D. Irwin, Sang-Jun Lee, Dale Li, John A. Mates, Christine G. Pappas, Daniel R. Schmidt, Charles Titus, Daniel Van Winkle, Joel N. Ullom, Abigail L. Wessels, Daniel S. Swetz
We are designing an array of transition-edge sensor (TES) microcalorimeters for a soft X-ray spectrometer at the Linac Coherent Light Source at SLAC National Accelerator Laboratory to coincide with upgrades to the free electron laser facility. The complete

A 300-mK Test Bed for Rapid Characterization of Microwave SQUID Multiplexing Circuits

August 3, 2018
Author(s)
Abigail L. Wessels, Daniel T. Becker, Douglas A. Bennett, Johnathon D. Gard, Johannes Hubmayr, Norman Jarosik, Vincent Y. Kotsubo, John A. Mates, Joel N. Ullom
Microwave SQUID multiplexing is a promising technique for multiplexing large arrays of transition edge sensors. A major bottleneck in the development and distribution of microwave SQUID multiplexer chips occurs in the time-intensive design testing and

A Scalable Readout for Microwave SQUID Multiplexing of Transition-Edge Sensors

July 9, 2018
Author(s)
Johnathon D. Gard, Daniel T. Becker, Douglas A. Bennett, Joseph W. Fowler, Gene C. Hilton, John A. Mates, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom
The readout requirements for instruments based on transition-edge sensors (TESs) have dramatically increased over the last decade as demand for systems with larger arrays and faster sensors has grown. Emerging systems are expected to contain many thousands

Dependence of transition width on current and critical current in transition-edge sensors

December 7, 2017
Author(s)
Kelsey M. Morgan, Christine G. Pappas, Douglas A. Bennett, Johnathon D. Gard, James P. Hays-Wehle, Gene C. Hilton, Carl D. Reintsema, Daniel R. Schmidt, Joel N. Ullom, Daniel S. Swetz
If transition-edge sensor (TES) X-ray detectors are to be useful in photon-rich environments,they must maintain high resolving power when pulse durations are engineered to be short, which is usually accomplished by increasing the thermal conductance (G)to

L-Edge Spectroscopy of Dilute, Radiation-Sensitive Systems Using a Transition-Edge-Sensor Array

December 7, 2017
Author(s)
Daniel S. Swetz, William B. Doriese, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kelsey M. Morgan, Galen C. O'Neil, Joel N. Ullom
We present X-ray absorption spectroscopy and resonant inelastic X-ray scattering (RIXS) measurements on the iron L-edge of 0.5 mM aqueous ferricyanide. These measurements demonstrate the ability of high-throughput transition- edge-sensor (TES)

Microwave SQUID Multiplexer for Cosmic Microwave Background Imagers

October 11, 2017
Author(s)
Bradley J. Dober, Daniel T. Becker, Douglas A. Bennett, Sean A. Bryan, Shannon M. Duff, Johnathon D. Gard, James P. Hays-Wehle, Johannes Hubmayr, John A. Mates, Carl D. Reintsema, Leila R. Vale
Key performance characteristics are demonstrated for the microwave SQUID multiplexer (µmux) coupled to transition edge sensor (TES) bolometers that have been optimized for cosmic microwave background (CMB) observations. In a 64-channel demonstration, we

Simultaneous readout of 128 X-ray and Gamma-ray Transition-edge Microcalorimeters using Microwave SQUID Multiplexing

August 8, 2017
Author(s)
John Mates, Dan Becker, Douglas Bennett, Johnathon Gard, James P. Hays-Wehle, Joseph Fowler, Gene C. Hilton, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Leila R. Vale, Joel Ullom
The number of elements in most cryogenic sensor arrays is limited by the technology available to multiplex signals from the array into a smaller number of wires and readout amplifiers. The largest demonstrated arrays of transition-edge sensor (TES)

A practical superconducting-microcalorimeter X-ray spectrometer for beamline and laboratory science

May 16, 2017
Author(s)
William B. Doriese, Peter Abbamonte, Douglas A. Bennett, Edward V. Denison, Yizhi Fang, Daniel A. Fischer, Colin P. Fitzgerald, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Cherno Jaye, Jessica L. McChesney, Luis Miaja Avila, Kelsey M. Morgan, Young Il Joe, Galen C. O'Neil, Carl D. Reintsema, Fanny Rodolakis, Daniel R. Schmidt, Hideyuki Tatsuno, Jens Uhlig, Leila R. Vale, Joel N. Ullom, Daniel S. Swetz
We describe a series of microcalorimeter X-ray spectrometers designed for a broad suite of measurement applications. The chief advantage of this type of spectrometer is that it can be orders of magnitude more efficient at collecting X-rays than more