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Search Publications by: James A. Beall (Fed)

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Displaying 51 - 75 of 216

Ultra-high resolution alpha particle spectroscopy using calorimetry

September 23, 2008
Author(s)
Robert D. Horansky, Joel N. Ullom, James A. Beall, Gene C. Hilton, Kent D. Irwin, Don Dry, Beth Hastings, Stephen Lamont, Clifford R. Rudy, Michael W. Rabin
Calorimetry has been used since the late 1700?s to measure the heat output of physical processes ranging from chemical reactions to the respiration of organisms . Calorimetry is performed by measuring the temperature change caused by heat release into a

High resolution X-ray transition-edge sensor cooled by tunnel junction refrigerators and operated above the transition temperature

April 21, 2008
Author(s)
Nathan A. Tomlin, Galen C. O\'Neil, James A. Beall, Gene C. Hilton, Kent D. Irwin, Daniel R. Schmidt, Leila R. Vale, Joel N. Ullom
We demonstrate cooling of an X-ray transition-edge sensor (TES) using solid-state refrigerators based on normal-metal / insulator / superconductor (NIS) tunnel junctions. We are able to operate the TES at a bath temperature of 260 mK, which is 75 mK above

An Optical System for Body Imaging from a Distance Using near-TeraHertz Frequencies

January 26, 2008
Author(s)
William Duncan, Robert E. Schwall, Kent D. Irwin, James A. Beall, Carl D. Reintsema, W.Bertrand (Randy) Doriese, Hsiao-Mei Cho, Brian Estey, Goutam Chattopadhyay, Peter Ade, Carole Tucker
We present the outline of the optical design of a TeraHertz (THz) imager for the detection of shrapnel-loaded improvised explosive devices (IED''s) at ''stand-off'' distances of 14 - 26 meters. The system will use 4 antenna-coupled TES detector arrays of

Analysis of Nuclear Material by Alpha Spectroscopy with a Transition-Edge Microcalorimeter

January 26, 2008
Author(s)
Rob Horansky, Joel Ullom, James A. Beall, Gene C. Hilton, Kent D. Irwin, Leila R. Vale, Don Dry, Stephen Lamont, Clifford R. Rudy, Michael W. Rabin
We present measurements from a cryogenic microcalorimeter designed to detect alpha particles. The enhanced resolution of microcalorimeter alpha detectors will provide new capabilities for actinide analysis. We demonstrate a spectral resolution of 2.4 keV

A TDMA Hybrid SQUID Multiplexer

January 25, 2008
Author(s)
Carl D. Reintsema, James A. Beall, W.Bertrand (Randy) Doriese, William Duncan, S. L. Ferreira, Gene C. Hilton, Kent D. Irwin, Dan Schmidt, Joel Ullom, Leila R. Vale, Yizi Xu
We have developed a multiplexed read-out for transition edge sensors based on a hybrid time- and frequency-domain basis set, similar to that used in time-division multiple-access (TDMA) mobile phones. The hybrid basis set uses bandwidth more efficiently

Large array of multiplexed gamma-ray microcalorimeters for nuclear-materials analysis

January 24, 2008
Author(s)
W.Bertrand (Randy) Doriese, Joel Ullom, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, John Mates, Carl D. Reintsema, Dan Schmidt, Leila R. Vale, Yizi Xu, Barry L. Zink, Michael W. Rabin, Minesh K. Bacrania, Stephen Lamont, Andrew Hoover, Clifford R. Rudy, Duc Vo, C. K. Stahle, Kevin R. Boyce, Larry E. Brown, Jonathan M. King, F. S. Porter
We are developing a gamma-ray spectrometer for the analysis of nuclear materials based on an array of superconducting transition-edge-sensor microcalorimeters. The instrument includes eight columns of time-division-SQUID multiplexing circuitry capable of

Operation of an X-ray transition-edge sensor cooled by tunnel junction refrigerators

January 19, 2008
Author(s)
Nathan A. Tomlin, James A. Beall, Gene C. Hilton, Kent D. Irwin, Galen O'Neil, Dan Schmidt, Leila R. Vale, Joel Ullom
We demonstrate successful cooling of an X-ray transition-edge sensor (TES) using solid-state refrigerators based on normal-metal/insulator/superconductor (NIS) tunnel junctions. Above the TES transition temperature (Tc), we use Johnson noise thermometry to

Multiplexed microcalorimeter arrays for precision measurements from microwave to gamma-ray wavelengths

August 21, 2007
Author(s)
Joel Ullom, W.Bertrand (Randy) Doriese, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, Terrence J. Jach, John Mates, Nathan A. Tomlin, Galen O'Neil, Carl D. Reintsema, Nicholas Ritchie, Dan Schmidt, Leila R. Vale, Yizi Xu, Barry L. Zink, Andrew Hoover, Clifford R. Rudy, Derek Tournear, Duc Vo, Michael W. Rabin
Cryogenic microcalorimeters are a promising technology for ultrasensitive measurements of electromagnetic radiation from microwave to gamma-ray wavelengths. Cryogenic microcalorimeters derive their exquisite sensitivity from the minimal thermal noise at

A 14-pixel, multiplexed array of gamma-ray microcalorimeters with 47 eV energy resolution at 103 keV

May 9, 2007
Author(s)
W.Bertrand (Randy) Doriese, Joel Ullom, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, John Mates, Carl D. Reintsema, Leila R. Vale, Yizi Xu, Barry L. Zink, Andrew Hoover, Michael W. Rabin, Clifford R. Rudy, Duc Vo
We present a prototype for a high-energy-resolution, high-count-rate, gamma-ray spectrometer intended for nuclear forensics and international nuclear safeguards. The prototype spectrometer is an array of 14 transition-edge-sensor microcalorimeters with an

Demonstration and modeling of an array-compatible TES microcalorimeter gamma-ray detector with 42 eV energy resolution at 103 keV

September 20, 2006
Author(s)
Barry L. Zink, Joel Ullom, James A. Beall, Kent D. Irwin, W.Bertrand (Randy) Doriese, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Carl D. Reintsema, Leila R. Vale
We describe a microcalorimeter gamma-ray detector with measured energy resolution of 42 eV full width at half maximum for 103 keV photons. This detector consists of a thermally isolated superconducting transition-edge thermometer and a superconducting bulk

Optimization of Transition-Edge Calorimeter Performance

April 15, 2006
Author(s)
Joel N. Ullom, James A. Beall, William B. Doriese, William Duncan, S. L. Ferreira, Gene C. Hilton, Kent D. Irwin, Galen C. O'Neil, Carl D. Reintsema, Leila R. Vale, Barry L. Zink
Calorimeters that exploit the superconducting-to-normal transition are used to detect individual photons from near-infrared to γ-ray wavelengths. Across this wide range, absorption efficiency, speed, and energy resolution are key performance parameters

Microwave SQUID multiplexers for low-temperature detectors

January 10, 2006
Author(s)
Kent D. Irwin, James A. Beall, W.Bertrand (Randy) Doriese, William Duncan, Gene C. Hilton, John Mates, Carl D. Reintsema, Dan Schmidt, Joel Ullom, Leila R. Vale, Barry L. Zink, Konrad Lehnert
We report on the development of a SQUID multiplexer operated at microwave frequencies. This multiplexer can accommodate any detector that can be read out with SQUIDs, including transition-edge sensors, magnetic calorimeters, and superconductor-insulator