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Search Publications by: Johnathon Gard (Assoc)

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Displaying 26 - 50 of 63

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)