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Search Publications by: Joel Ullom (Fed)

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Displaying 76 - 100 of 173

A Thin-Film Cryotron Suitable For Use as an Ultra-Low-Temperature Switch

October 6, 2016
Author(s)
Peter J. Lowell, John A. Mates, William B. Doriese, Gene C. Hilton, Kelsey M. Morgan, Daniel S. Swetz, Joel N. Ullom, Daniel R. Schmidt
Low-temperature superconducting circuits have become important in modern science. However, there are presently no high-current-capacity switches with low power dissipation for sub-Kelvin operation. One candidate for a sub-Kelvin switch is the cryotron, a

First application of superconducting transition-edge-sensor microcalorimeters to hadronic-atom x-ray spectroscopy

September 30, 2016
Author(s)
Douglas Bennett, W.Bertrand (Randy) Doriese, Joseph Fowler, Johnathon Gard, James P. Hays-Wehle, Gene C. Hilton, Carl D. Reintsema, Daniel Swetz, Joel Ullom
High-resolution pionic-atom x-ray spectroscopy was performed with an x-ray spectrometer based on a 240-pixel array of superconducting transition-edge-sensor (TES)microcalorimeters at the πM1 beam line of the Paul Scherrer Institute. The pionic-carbon 4 → 3

Ultrafast time-resolved hard x-ray emission spectroscopy on a table top

September 27, 2016
Author(s)
Luis Miaja Avila, Galen C. O'Neil, Young Il Joe, Bradley K. Alpert, Niels Damrauer, William B. Doriese, Steven Fatur, Joseph W. Fowler, Gene C. Hilton, Ralph Jimenez, Carl D. Reintsema, Daniel R. Schmidt, Kevin L. Silverman, Daniel S. Swetz, Hideyuki Tatsuno, Joel N. Ullom
Chemical reactions driven by light are fundamental to biology and a source of inspiration for engineering materials to perform tasks such as solar energy harvesting and data storage. Observing and understanding photodynamics requires experimental tools

Code-division-multiplexed readout of large arrays of TES microcalorimeters

September 15, 2016
Author(s)
Kelsey M. Morgan, Bradley K. Alpert, Douglas A. Bennett, William B. Doriese, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kent D. Irwin, Young Il Joe, Galen C. O'Neil, Carl D. Reintsema, Edward V. Denison, Daniel R. Schmidt, Joel N. Ullom, Daniel S. Swetz
Code-division multiplexing (CDM) offers a path to reading out large arrays of transition edge sensor (TES) X-ray micro-calorimeters with excellent energy and timing resolution. We demonstrate the readout of X-ray TESs with a 32-channel flux-summed code

Design of 280 GHz feedhorn-coupled TES arrays for the balloon-borne polarimeter SPIDER

July 7, 2016
Author(s)
Johannes Hubmayr, Jason E. Austermann, James A. Beall, Daniel T. Becker, Shannon M. Duff, Arpi L. Grigorian, Gene C. Hilton, Joel N. Ullom, Michael R. Vissers
We describe 280 GHz bolometric detector arrays that instrument the balloon-borne polarimeter spider. A primary science goal of spider is to measure large-scale B-mode polarization of the cosmic microwave back-ground (cmb) in search of the cosmic-inflation

Absolute Energy Calibration of X-ray TESs with 0.04 eV Uncertainty at 6.4 keV in a Hadron-Beam Environment

January 19, 2016
Author(s)
Hideyuki Tatsuno, William B. Doriese, Douglas A. Bennett, Catalina Curceanu, Joseph W. Fowler, Johnathon D. Gard, Fredrick P. Gustafsson, Tadashi Hashimoto, Ryugo S. Hayano, James P. Hays-Wehle, Gene C. Hilton, Mihail Iliescu, Shigeru Ishimoto, Kenta Itahashi, Masashiko Iwasaki, Keisuke Kuwabara, Yue Ma, Johann Marton, Hirofumi Noda, Galen C. O'Neil, Shinji Okada, Haruhiko Outa, Carl D. Reintsema, Masaharu Sato, Daniel R. Schmidt, Hexi Shi, Ken Suzuki, Takatoshi Suzuki, Jens Uhlig, Joel N. Ullom, Eberhard Widmann, Shinya Yamada, Johann Zmeskal, Daniel S. Swetz
A performance evaluation of superconducting transition-edge sensors (TESs) in the environment of a pion beam line at a particle accelerator is presented. Averaged across the 209 functioning sensors in the array, the achieved energy resolution is 5.2 eV

Algorithms for Identification of Nearly-Coincident Events in Calorimetric Sensors

December 29, 2015
Author(s)
Bradley K. Alpert, Elena Ferri, Douglas A. Bennett, Marco Faverzani, Joseph W. Fowler, Andrea Giachero, James P. Hays-Wehle, Angelo Nucciotti, Daniel S. Swetz, Joel N. Ullom
For experiments with high arrival rates, reliable identification of nearly-coincident events can be crucial. For calorimetric measurements to directly measure the neutrino mass such as HOLMES, unidentified pulse pile-ups are expected to comprise a leading

Developments in time-division multiplexing of X-ray transition-edge sensors.

December 8, 2015
Author(s)
William B. Doriese, Kelsey M. Morgan, Douglas A. Bennett, Edward V. Denison, Colin P. Fitzgerald, Joseph W. Fowler, Johnathon D. Gard, James P. Hays-Wehle, Gene C. Hilton, Kent D. Irwin, Young Il Joe, John A. Mates, Galen C. O'Neil, Carl D. Reintsema, Nigel O. Robbins, Daniel R. Schmidt, Daniel S. Swetz, Hideyuki Tatsuno, Joel N. Ullom, Leila R. Vale
Time-division multiplexing (TDM) is a mature scheme for the readout of transition-edge sensors. Variants of TDM, which is based on superconducting-quantum-interference-device (SQUID) current amplifiers, have to date been field-deployed in several

Observation of Iron Spin-States using Tabletop X-ray Emission Spectroscopy and Microcalorimeter Sensors

December 2, 2015
Author(s)
Young Il Joe, Galen C. O'Neil, Luis Miaja Avila, Joseph W. Fowler, Kevin L. Silverman, Daniel S. Swetz, Joel N. Ullom, Ralph Jimenez
X-ray emission spectroscopy (XES) is a powerful probe of the electronic and chemical state of elemental species embedded within more complex compounds. X-ray sensors that combine high resolving power and high collecting efficiency are desirable for photon

The Practice of Pulse Processing

November 12, 2015
Author(s)
Joseph W. Fowler, Bradley K. Alpert, William B. Doriese, Young Il Joe, Galen C. O'Neil, Joel N. Ullom, Daniel S. Swetz
The analysis of data from x-ray microcalorimeters requires great care; their excellent intrinsic energy resolution cannot usually be achieved in practice without a statistically near-optimal pulse analysis and corrections for important systematic errors

Microcalorimeter Spectroscopy at High Pulse Rates: a Multi-Pulse Fitting Technique

August 24, 2015
Author(s)
Joseph W. Fowler, Bradley K. Alpert, William B. Doriese, Young Il Joe, Galen C. O'Neil, Cherno Jaye, Joel N. Ullom, Daniel A. Fischer, Daniel S. Swetz
Transition edge sensor microcalorimeters can measure x-ray and gamma-ray energies with very high energy resolution and high photon-collection efficiency. For this technology to reach its full potential in future x-ray observatories, each sensor must be

Macroscopic Subkelvin Refrigerator Employing Superconducting Tunnel Junctions

August 10, 2015
Author(s)
Xiaohang NMN Zhang, Peter J. Lowell, Brandon L. Wilson, Galen C. O'Neil, Joel N. Ullom
In this paper, we demonstrate a general-purpose macroscopic refrigerator based on the transport of hot electrons through superconducting tunnel junctions. Our refrigerator is intended to provide access to temperatures below those accessible using pumped

Thermal Conductance Engineering for High-Speed TES Microcalorimeters

July 22, 2015
Author(s)
James P. Hays-Wehle, Daniel R. Schmidt, Joel N. Ullom, Daniel S. Swetz
Many current and future applications for superconducting transition-edge sensor (TESmicrocalorimeters require significantly faster pulse-response than is currently available. X-ray spectroscopy experiments at next-generation synchrotron light sources need

High-resolution X-ray emission spectroscopy with transition-edge sensors: present performance and future potential

May 1, 2015
Author(s)
W.Bertrand (Randy) Doriese, Joseph Fowler, Daniel Swetz, Cherno Jaye, Daniel A. Fischer, Carl D. Reintsema, Douglas Bennett, Leila R. Vale, Gene C. Hilton, Dan Schmidt, Joel Ullom, Jens Uhlig, Ujjwal Mandal, Galen O'Neil, Luis Miaja Avila, Young I. Joe, wilfrid fullagar, Fredrick P. Gustafsson, Dharma Kurunthu, Villy Sundstrom
X-ray emission spectroscopy (XES) is a powerful element-selective tool to analyze the oxidation states of atoms in complex compounds, determine their electronic configuration, and identify unknown compounds in challenging environments. Until now the low

Measurement of the 240Pu/239Pu Mass Ratio Using a Transition-Edge-Sensor Microcalorimeter for Total Decay Energy Spectroscopy

February 27, 2015
Author(s)
Daniel R. Schmidt, Douglas A. Bennett, James P. Hays-Wehle, Daniel S. Swetz, Joel N. Ullom, Andrew Hoover, Mark Croce, Michael W. Rabin, Evelyn Bond, Terry Holesinger, Gerd Kunde, Laura Wolfsbereg
We have developed a new category of sensor for measurement of the 240Pu/239Pu mass ratio from aqueous solution samples with advantages over existing methods. Aqueous solution plutonium samples were evaporated and encapsulated inside of a gold foil absorber

Integration of TES microcalorimeters with microwave SQUID multiplexed readout.

December 22, 2014
Author(s)
Douglas A. Bennett, John A. Mates, Johnathon D. Gard, Andrew Hoover, Micheal Rabin, Carl D. Reintsema, Daniel R. Schmidt, Leila R. Vale, Joel N. Ullom
The demonstration of a microwave SQUID multiplexed readout of transition-edge sensor (TES) microcalorimeters has the potential to dramatically expand the scale of arrays of TESs. In this manuscript we discuss recent work to develop an instrument for high

Phase-slip lines as a resistance mechanism in transition-edge sensors

January 27, 2014
Author(s)
Douglas A. Bennett, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom
The fundamental mechanism of resistance in voltage-biased superconducting films is poorly understood despite its importance as the basis of transition-edge sensors (TESs). TESs are utilized in state-of- the-art microbolometers and microcalorimeters

Sub-100 mK cooling using normal-metal?insulator?superconductor tunnel junctions

December 15, 2013
Author(s)
Peter J. Lowell, Galen C. O'Neil, Jason M. Underwood, Xiaohang NMN Zhang, Joel N. Ullom
Normal-metal∖insulator∖superconductor (NIS) junctions can be used as solid-state refrigerators since the hottest electrons preferentially tunnel from the normal metal into the superconductor. In this paper, we present NIS junctions optimized to cool

Identification and elimination of anomalous thermal decay in gamma-ray microcalorimeters

November 18, 2013
Author(s)
Robert D. Horansky, Douglas A. Bennett, Daniel R. Schmidt, Barry L. Zink, Joel N. Ullom
Microcalorimeter detectors rely on superconducting components and cryogenic temperatures to provide over an order-of-magnitude improvement in energy resolution compared to semiconducting sensors. Resolution improvements impact fields from gamma-ray

High resolution gamma-ray spectroscopy with a microwave-multiplexed TES array

November 11, 2013
Author(s)
Omid Noroozian, John A. Mates, Douglas A. Bennett, Justus A. Brevik, Joseph W. Fowler, Jiansong Gao, Robert D. Horansky, Kent D. Irwin, Daniel R. Schmidt, Joel N. Ullom, Zhao Kang
We demonstrate the first gamma-ray spectroscopy with a microwave-multiplexed two-pixel TES(transition-edge sensor) array. We measured a $^{153}$Gd photon source and achieved an energy resolution of 63 eV full-width-at-half-maximum (FWHM) at 97 keV and an

Lattice damage in superconducting microcalorimeter detectors

June 3, 2013
Author(s)
Robert D. Horansky, Joel N. Ullom, Michael W. Rabin
There is currently significant interest in using superconducting detectors for measurement of ion kinetic energies. Unprecedented resolution is possible with an order of magnitude improvement over semiconductors. Superconducting detectors are now able to

Operation of gamma-ray microcalorimeters at elevated count rates using filters with constraints

May 15, 2013
Author(s)
Bradley K. Alpert, Robert D. Horansky, Douglas A. Bennett, William B. Doriese, Joseph W. Fowler, Andrew Hoover, Michael W. Rabin, Joel N. Ullom
We introduce a filter construction method for pulse processing that differs in two respects from that in standard optimal filtering, in which the average pulse shape and noise power spectral density are combined to create a convolution filter for

Table-top ultrafast x-ray microcalorimeter spectrometry for molecular structure

March 26, 2013
Author(s)
Jens (. Uhlig, William B. Doriese, Joseph W. Fowler, Daniel S. Swetz, Carl D. Reintsema, Douglas A. Bennett, Leila R. Vale, Gene C. Hilton, Kent D. Irwin, Joel N. Ullom, Ilari Maasilta, Wilfred Fullagar, Niklas Gador, Sophie Canton, Kimmo Kinnunen, Villy Sundstrom
This work presents an x-ray absorption measurement by use of ionizing radiation generated by a femtosecond pulsed laser source. The spectrometer was a microcalorimetric array whose pixels are capable of accurately measuring energies of individual radiation