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Search Publications by: Joel Ullom (Fed)

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Displaying 126 - 150 of 350

Resonator Stabilization Architecture to Suppress Switching Transient Crosstalk in I-CDM

May 30, 2018
Author(s)
Malcolm S. Durkin, Joel C. Weber, William B. Doriese, Gene C. Hilton, Daniel S. Swetz, Joel N. Ullom
The ever-increasing sizes of transition-edge sensor (TES) microcalorimeter arrays motivates improved multiplexed readout with large multiplexing factors, low power dissipation, and low levels of crosstalk. Current-summed code division multiplexing (I-CDM)

Approaches to the Optimal Nonlinear Analysis of Microcalorimeter Pulses

March 8, 2018
Author(s)
Joseph W. Fowler, Christine G. Pappas, Bradley K. Alpert, William B. Doriese, Galen C. O'Neil, Joel N. Ullom, Daniel S. Swetz
We consider how to analyze microcalorimeter pulses for quantities that are nonlinear in the data, while preserving the signal-to-noise advantages of linear optimal filtering. We apply the approach to compute the electrothermal feedback energy deficit (the

Millimeter-Wave Polarimeters Using Kinetic Inductance Detectors for TolTEC and Beyond

March 8, 2018
Author(s)
Jason Austermann, James A. Beall, Sean A. Bryan, Bradley Dober, Jiansong Gao, Gene C. Hilton, Johannes Hubmayr, Phillip Mauskopf, Christopher M. McKenney, S M. Simon, Joel Ullom, Michael Vissers, G W. Wilson
Microwave kinetic inductance detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the

Superconducting micro-resonator arrays with ideal frequency spacing

December 20, 2017
Author(s)
Xiangliang Liu, Weijie Guo, Y Wang, M Dai, L F. Wei , Bradley J. Dober, Christopher M. McKenney, Gene C. Hilton, Johannes Hubmayr, Jason E. Austermann, Joel Ullom, Jiansong Gao, Michael Vissers
We present a wafer trimming technique for producing superconducting micro-resonator arrays with highly uniform frequency spacing. With the light-emitting diode mapper technique demonstrated previously, we first map the measured resonance frequencies to the

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)

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 Reassessment of Absolute Energies of X-ray L Lines of Lanthanide Metals

June 28, 2017
Author(s)
Bradley Alpert, W.Bertrand (Randy) Doriese, Gene C. Hilton, Lawrence T. Hudson, Young I. Joe, Kelsey Morgan, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Csilla Szabo-Foster, Joel Ullom, Joseph Fowler, Galen O'Neil, Douglas Bennett
We introduce a new technique for determining x-ray fluorescence line energies and widths, and we present measurements made with this technique of 22 x-ray L lines from lanthanide-series elements. The technique uses arrays of transition-edge sensors

Counting Near Infrared Photons with Microwave Kinetic Inductance Detectors

May 22, 2017
Author(s)
Jiansong Gao, Michael R. Vissers, Joel N. Ullom, Johannes Hubmayr, Joseph W. Fowler, Leila R. Vale, Weijie Guo
We demonstrate photon counting at 1550~nm wavelength using microwave kinetic inductance detectors (MKIDs) made from TiN/Ti/TiN trilayer films with superconducting transition temperature $T_{c} \sim$ 1.4~K. The detector has a lump-element design with a

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

Beating Darwin-Bragg losses in lab-based ultrafast x-ray experiments

March 24, 2017
Author(s)
Wilfred Fullagar, Jens Uhlig, Ujjwal Mandal, Dharma Kurunthu, Amal El Nahhas, Hideyuki Tatsuno, Alireza Honarfar, Fredrik Gustafsson, Villy Sundstrom, Mikko Palosaari, Luis Miaja Avila, Young I. Joe, Daniel Swetz, Joel Ullom
The use of low temperature thermal detectors for avoiding Darwin-Bragg losses in lab-based ultrafast experiments has begun. An outline of the background of this new development is offered, showing the relevant history and initiative taken by this work.

Ultrafast time-resolved x-ray absorption spectroscopy of ferrioxalate photolysis with a laser plasma x-ray source and microcalorimeter array

February 17, 2017
Author(s)
Galen C. O'Neil, Joel N. Ullom, Luis Miaja Avila, Young Il Joe, Joseph W. Fowler, Carl D. Reintsema, Daniel S. Swetz, Kevin L. Silverman, Daniel R. Schmidt, Bruce D. Ravel, Gene C. Hilton, William B. Doriese, Bradley K. Alpert, Ralph Jimenez
Using a table-top apparatus based upon a laser plasma x-ray source and an array of cryogenic microcalorimeter x-ray detectors, we have measured the transient x-ray absorption spectrum during the ferrioxalate photoreduction reaction. We observe the Fe K

Compact 2.2 K Cooling System for Superconducting Nanowire Single Photon Detectors

January 25, 2017
Author(s)
Vincent Y. Kotsubo, Ray Radebaugh, Sae Woo Nam, Joel N. Ullom, Brandon L. Wilson, Paul Hendershott, Micheal Bonczyski
We are developing a compact, low power, closed cycle cooling system for Superconducting Nanowire Single Photon Detectors. The base temperature of the present prototype, which uses a helium-4 Joule-Thomson stage, is 2.2 K with over 1.2 mW of cooling. This