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Search Publications by: David A. Wollman (Fed)

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Displaying 51 - 75 of 75

Microcalorimeter EDS: Benefits and Drawbacks

August 1, 2000
Author(s)
David A. Wollman, Dale Newbury, Sae Woo Nam, Gene C. Hilton, Kent D. Irwin, David A. Rudman, Steven Deiker, Norman F. Bergren, John M. Martinis
The commercial introduction of high-count-rate, near-room-temperature silicon drift detectors (presently available) and high-energy-resolution cryogenic microcalorimeters (forthcoming) is an exciting development in x-ray microanalysis, in which detector

Microcalorimeter Energy-Dispersive Spectrometry Using a Low Voltage Scanning Electron Microscope

July 1, 2000
Author(s)
David A. Wollman, Sae Woo Nam, Gene C. Hilton, Kent D. Irwin, Norman F. Bergren, David A. Rudman, John M. Martinis, Dale Newbury
We describe the current performance of the prototype microcalorimeter energy-dispersive spectrometer (5cal EDS) developed at NIST for X-ray microanalysis. We show that the low-energy 5cal EDS, designed for operation in the energy range 0.2-2 keV, offers

The Approaching Revolution in X-Ray Microanalysis: The Microcalorimeter Energy Dispersive Spectrometer

June 1, 2000
Author(s)
Dale E. Newbury, David A. Wollman, Gene C. Hilton, Kent D. Irwin, Norman F. Bergren, David A. Rudman, John M. Martinis
We have developed a high-resolution energy-dispersive x-ray spectrometer (EDS) based on cryogenic microcalorimeter x-ray detectors for use in x-ray microanalysis. With an energy resolution of 3 eV at 1.5 keV, count rate of {approximately} 500 s -1, and an

Application of Microcalorimeter EDS X-Ray Detectors to Particle Analysis

December 1, 1999
Author(s)
Alain C. Diebold, David A. Wollman, Gene C. Hilton, Kent D. Irwin, John M. Martinis, B. H. Liu
New microcalorimeter x-ray detector technology will revolutionize materials characterization. It is expected that the microcalorimeter EDS (energy dispersive spectrometer) will replace traditional lithium-drifted silicon semiconductor EDS due to its

Energy Dispersive X-Ray Spectrometry With the Transition Edge Sensor Microcalorimeter: A Revolutionary Advance in Materials Microanalysis

December 1, 1999
Author(s)
Dale E. Newbury, David A. Wollman, Kent D. Irwin, Gene C. Hilton, John M. Martinis
The NIST microcalorimeter energy dispersive x-ray spectrometer provides important advances in x-ray spectrometry. The high spectral resolution, approaching 2 eV for photon energies below 2 keV, the wide photon energy coverage, 250 eV to 10 keV, and the

Toward a 2-eV Microcalorimeter X-ray Spectrometer for Constellation-X

October 1, 1999
Author(s)
C. K. Stahle, Simon R. Bandler, T W. Barbee, J. Beeman, R.P. Brekosky, B. Cabrera, M. Cunningham, Steven Deiker, Enectali Figueroa-Feliciano, F. M. Finkbeiner, G R. Frank, K. C. Gendreau, E. E. Haller, Gene C. Hilton, Kent D. Irwin, R. L. Kelley, S. E. Labov, M. J. Li, N. Madden, John M. Martinis, D. McCammon, Sae Woo Nam, F. S. Porter, H. Schnopper, E. H. Silver, A. E. Szymkowiak, G. S. Tucker, A. Walker, David A. Wollman
Constellation-X is a cluster of identical observatories that together constitute a promising concept for a next-generation, high-throughput, high-resolution, astrophysical x-ray spectroscopy mission. The heart of the Constellation-X mission concept is a

Lowering the Limit of Detection in High Spatial Resolution Electron Beam Microanalysis With the Microcalorimeter Energy Dispersive X-Ray Spectrometer

June 1, 1999
Author(s)
Dale E. Newbury, David A. Wollman, Kent D. Irwin, Gene C. Hilton, John M. Martinis
Low-beam-energy x-ray microanalysis with the field-emission-gun scanning electron microscope suffers limitations due to physical factors of x-ray generation. Instrumental limitations are imposed by the poor resolution of the conventional semiconductor

Microcalorimeter EDS Measurements of Chemical Shifts in Fe Compounds

July 1, 1998
Author(s)
David A. Wollman, Dale E. Newbury, Gene C. Hilton, Kent D. Irwin, L L. Dulcie, Norman F. Bergren, John M. Martinis
Chemical shifts result from changes in electron binding energies with the chemical environment of atoms. In x-ray spectra, chemical shifts lead to changes in x-ray peak positions, relative peak intensities, and peak shapes. These chemical bonding effects

Thermal-Response Time of Superconducting Transition-Edge Microcalorimeters

April 1, 1998
Author(s)
Kent D. Irwin, Gene C. Hilton, David A. Wollman, John M. Martinis
We investigate limits on the thermal-response time of supercondcuting transition-edge microcalorimeters. For operation at 0.1 K, we show that the lower limit on the response time of a superconducting transition-edge microcalorimeter is of order 1 5m due to

High-Resolution, Energy-Dispersive Microcalorimeter Spectrometer for X-Ray Microanalysis

December 1, 1997
Author(s)
David A. Wollman, Kent D. Irwin, Gene C. Hilton, L L. Dulcie, Dale E. Newbury, John M. Martinis
We have developed a prototype X‐ray microcalorimeter spectrometer with high energy resolution for use in X‐ray microanalysis. The microcalorimeter spectrometer system consists of a superconducting transition‐edge sensor X‐ray microcalorimeter cooled to an

Superconducting Microcalorimeter X-ray Spectrometers

June 1, 1997
Author(s)
John M. Martinis, David A. Wollman, Kent D. Irwin, Gene C. Hilton
A revolutionary advance in x-ray microanalysis will occur in the next few years due to the development of new x-ray spectrometers based on microcalorimeters. These detectors will be similar in operation to commonly-used energy dispersive spectrometers (EDS