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Eckart ME, Beiersdorfer P, Brown GV, Den Hartog DJ, Hell N, Kelley RL, Kilbourne CA, Magee EW, Mangoba AEY, Nornberg MD, Porter FS, Reusch LM, Wallace JP. Microcalorimeter measurement of x-ray spectra from a high-temperature magnetically confined plasma. Rev Sci Instrum 2021; 92:063520. [PMID: 34243585 DOI: 10.1063/5.0043980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 04/29/2021] [Indexed: 06/13/2023]
Abstract
A NASA-built x-ray microcalorimeter spectrometer has been installed on the MST facility at the Wisconsin Plasma Physics Laboratory and has recorded x-ray photons emitted by impurity ions of aluminum in a majority deuterium plasma. Much of the x-ray microcalorimeter development has been driven by the needs of astrophysics missions, where imaging arrays with few-eV spectral resolution are required. The goal of our project is to adapt these single-photon-counting microcalorimeters for magnetic fusion energy research and demonstrate the value of such measurements for fusion science. Microcalorimeter spectrometers combine the best characteristics of the x-ray instrumentation currently available on fusion devices: high spectral resolution similar to an x-ray crystal spectrometer and the broadband coverage of an x-ray pulse height analysis system. Fusion experiments are increasingly employing high-Z plasma-facing components and require measurement of the concentration of all impurity ion species in the plasma. This diagnostic has the capability to satisfy this need for multi-species impurity ion data and will also contribute to measurements of impurity ion temperature and flow velocity, Zeff, and electron density. Here, we introduce x-ray microcalorimeter detectors and discuss the diagnostic capability for magnetic fusion energy experiments. We describe our experimental setup and spectrometer operation approach at MST, and we present the results from an initial measurement campaign.
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Affiliation(s)
- M E Eckart
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P Beiersdorfer
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - G V Brown
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D J Den Hartog
- Wisconsin Plasma Physics Laboratory, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - N Hell
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R L Kelley
- X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C A Kilbourne
- X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - E W Magee
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A-E Y Mangoba
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - M D Nornberg
- Wisconsin Plasma Physics Laboratory, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - F S Porter
- X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - L M Reusch
- Wisconsin Plasma Physics Laboratory, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - J P Wallace
- Wisconsin Plasma Physics Laboratory, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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2
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Leutenegger MA, Eckart ME, Moseley SJ, Rohrbach SO, Black JK, Chiao MP, Kelley RL, Kilbourne CA, Porter FS. Simple, compact, high-resolution monochromatic x-ray source for characterization of x-ray calorimeter arrays. Rev Sci Instrum 2020; 91:083110. [PMID: 32872938 DOI: 10.1063/5.0005206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 08/02/2020] [Indexed: 06/11/2023]
Abstract
X-ray calorimeters routinely achieve very high spectral resolution, typically a few eV full width at half maximum (FWHM). Measurements of calorimeter line shapes are usually dominated by the natural linewidth of most laboratory calibration sources. This compounds the data acquisition time necessary to statistically sample the instrumental line broadening and can add systematic uncertainty if the intrinsic line shape of the source is not well known. To address these issues, we have built a simple, compact monochromatic x-ray source using channel cut crystals. A commercial x-ray tube illuminates a pair of channel cut crystals that are aligned in a dispersive configuration to select the Kα1 line of the x-ray tube anode material. The entire device, including the x-ray tube, can be easily hand-carried by one person and may be positioned manually or using a mechanical translation stage. The output monochromatic beam provides a collimated image of the anode spot with magnification of unity in the dispersion direction (typically 100 μm-200 μm for the x-ray tubes used here) and is unfocused in the cross-dispersion direction so that the source image in the detector plane appears as a line. We measured output count rates as high as 10 count/s/pixel for the Hitomi soft x-ray spectrometer, which had 819 μm square pixels. We implemented different monochromator designs for energies of 5.4 keV (one design) and 8.0 keV (two designs), which have effective theoretical FWHM energy resolution of 0.125 eV, 0.197 eV, and 0.086 eV, respectively; these are well-suited for optimal calibration measurements of state-of-the art x-ray calorimeters. We measured an upper limit for the energy resolution of our Cr Kα1 monochromator of 0.7 eV FWHM at 5.4 keV, consistent with the theoretical prediction of 0.125 eV.
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Affiliation(s)
- M A Leutenegger
- Code 662, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - M E Eckart
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - S J Moseley
- Code 662, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - S O Rohrbach
- Code 551, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - J K Black
- Rock Creek Scientific, 1400 East-West Hwy, Suite 807, Silver Spring, Maryland 20910, USA
| | - M P Chiao
- Code 592, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - R L Kelley
- Code 662, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C A Kilbourne
- Code 662, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - F S Porter
- Code 662, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
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3
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Durkin M, Adams JS, Bandler SR, Chervenak JA, Chaudhuri S, Dawson CS, Denison EV, Doriese WB, Duff SM, Finkbeiner FM, FitzGerald CT, Fowler JW, Gard JD, Hilton GC, Irwin KD, Joe YI, Kelley RL, Kilbourne CA, Miniussi AR, Morgan KM, O'Neil GC, Pappas CG, Porter FS, Reintsema CD, Rudman DA, SaKai K, Smith SJ, Stevens RW, Swetz DS, Szypryt P, Ullom JN, Vale LR, Wakeham N, Weber JC, Young BA. Demonstration of Athena X-IFU Compatible 40-Row Time-Division-Multiplexed Readout. IEEE Trans Appl Supercond 2019; 29:2101005. [PMID: 31160861 PMCID: PMC6544157 DOI: 10.1109/tasc.2019.2904472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Time-division multiplexing (TDM) is the backup readout technology for the X-ray Integral Field Unit (X-IFU), a 3,168-pixel X-ray transition-edge sensor (TES) array that will provide imaging spectroscopy for ESA's Athena satellite mission. X-0IFU design studies are considering readout with a multiplexing factor of up to 40. We present data showing 40-row TDM readout (32 TES rows + 8 repeats of the last row) of TESs that are of the same type as those being planned for X-IFU, using measurement and analysis parameters within the ranges specified for X-IFU. Singlecolumn TDM measurements have best-fit energy resolution of (1.91 ± 0.01) eV for the Al Kα complex (1.5 keV), (2.10 ± 0.02) eV for Ti Kα (4.5 keV), (2.23 ± 0.02) eV for Mn Kα (5.9 keV), (2.40 ± 0.02) eV for Co Kα (6.9 keV), and (3.44 ± 0.04) eV for Br Kα (11.9 keV). Three-column measurements have best-fit resolution of (2.03 ± 0.01) eV for Ti Kα and (2.40 ± 0.01) eV for Co Kα. The degradation due to the multiplexed readout ranges from 0.1 eV at the lower end of the energy range to 0.5 eV at the higher end. The demonstrated performance meets X-IFU's energy-resolution and energy-range requirements. True 40-row TDM readout, without repeated rows, of kilopixel scale arrays of X-IFU-like TESs is now under development.
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Affiliation(s)
- M Durkin
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - J S Adams
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - S R Bandler
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - J A Chervenak
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - S Chaudhuri
- Stanford University Dept. of Physics, Stanford, CA 94305 USA
| | - C S Dawson
- Stanford University Dept. of Physics, Stanford, CA 94305 USA
| | - E V Denison
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - W B Doriese
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - S M Duff
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - F M Finkbeiner
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - C T FitzGerald
- Santa Clara University Dept. of Physics, Santa Clara, CA 95053 USA
| | - J W Fowler
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - J D Gard
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - G C Hilton
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - K D Irwin
- Stanford University Dept. of Physics, Stanford, CA 94305 USA
| | - Y I Joe
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - R L Kelley
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - C A Kilbourne
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - A R Miniussi
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - K M Morgan
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - G C O'Neil
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - C G Pappas
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - F S Porter
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - C D Reintsema
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - D A Rudman
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - K SaKai
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - S J Smith
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - R W Stevens
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - D S Swetz
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - P Szypryt
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - J N Ullom
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - L R Vale
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - N Wakeham
- National Aeronautics and Space Administration, Greenbelt, MD 20771 USA
| | - J C Weber
- National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - B A Young
- Santa Clara University Dept. of Physics, Santa Clara, CA 95053 USA
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4
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Jaeckel FT, Ambarish CV, Christensen N, Gruenke R, Hu L, McCammon D, McPheron M, Meyer M, Nelms KL, Roy A, Wulf D, Zhang S, Zhou Y, Adams JS, Bandler SR, Chervenak JA, Datesman AM, Eckart ME, Ewin AJ, Finkbeiner FM, Kelley R, Kilbourne CA, Miniussi AR, Porter FS, Sadleir JE, Sakai K, Smith SJ, Wakeham N, Wassell E, Yoon W, Morgan KM, Schmidt DR, Swetz DS, Ullom JN. Energy calibration of high-resolution X-Ray TES microcalorimeters with 3 eV optical photons. IEEE Trans Appl Supercond 2019; 29:2100104. [PMID: 31186605 PMCID: PMC6557579 DOI: 10.1109/tasc.2019.2899856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
With the improving energy resolution of transitionedge sensor (TES) based microcalorimeters, performance verification and calibration of these detectors has become increasingly challenging, especially in the energy range below 1 keV where fluorescent atomic X-ray lines have linewidths that are wider than the detector energy resolution and require impractically high statistics to determine the gain and deconvolve the instrumental profile. Better behaved calibration sources such as grating monochromators are too cumbersome for space missions and are difficult to use in the lab. As an alternative, we are exploring the use of pulses of 3 eV optical photons delivered by an optical fiber to generate combs of known energies with known arrival times. Here, we discuss initial results of this technique obtained with 2 eV and 0.7 eV resolution X-ray microcalorimeters. With the 2 eV detector, we have achieved photon number resolution for pulses with mean photon number up to 133 (corresponding to 0.4 keV).
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Affiliation(s)
- F T Jaeckel
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - C V Ambarish
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - N Christensen
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - R Gruenke
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - L Hu
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - D McCammon
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - M McPheron
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - M Meyer
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - K L Nelms
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - A Roy
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - D Wulf
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - S Zhang
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - Y Zhou
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706
| | - J S Adams
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - S R Bandler
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - J A Chervenak
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - A M Datesman
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - M E Eckart
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - A J Ewin
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - F M Finkbeiner
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - R Kelley
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - C A Kilbourne
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - A R Miniussi
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - F S Porter
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - J E Sadleir
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - K Sakai
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - S J Smith
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - N Wakeham
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - E Wassell
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - W Yoon
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771
| | - K M Morgan
- National Institute for Standards and Technology, 325 Broadway, Boulder, CO 80305
| | - D R Schmidt
- National Institute for Standards and Technology, 325 Broadway, Boulder, CO 80305
| | - D S Swetz
- National Institute for Standards and Technology, 325 Broadway, Boulder, CO 80305
| | - J N Ullom
- National Institute for Standards and Technology, 325 Broadway, Boulder, CO 80305
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5
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DeNigris NS, Chervenak JA, Bandler SR, Chang MP, Costen NP, Eckart ME, Ha JY, Kilbourne CA, Smith SJ. Fabrication of Flexible Superconducting Wiring with High Current-Carrying Capacity Indium Interconnects. J Low Temp Phys 2018; 193:687-694. [PMID: 31359888 PMCID: PMC6662641 DOI: 10.1007/s10909-018-2019-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 07/03/2018] [Indexed: 06/10/2023]
Abstract
The X-ray integral field unit (X-IFU) is a cryogenic spectrometer for the Advanced Telescope for High ENergy Astrophysics (ATHENA). ATHENA is a planned next-generation space-based X-ray observatory with capabilities that surpass the spectral resolution of prior missions. Proposed device designs contain up to 3840 transition edge sensors, each acting as an individual pixel on the detector, presenting a unique challenge for wiring superconducting leads in the focal plane assembly. In prototypes that require direct wiring, the edges of X-IFU focal plane have hosted aluminum wirebonding pads; however, indium (In) 'bumps' deposited on an interface layer such as molybdenum nitride (MoN) can instead be used as an array of superconducting interconnects. We investigated bumped MoN:In structures with different process cleans and layer thicknesses. Measurements of the resistive transitions showed variation of transition temperature T c as a function of bias and generally differed from the expected bulk T c of In (3.41 K). Observed resistance of the In bump structures at temperatures below the MoN transition (at 8.0 K) also depended on the varied parameters. For our proposed X-IFU geometry (10 μm of In mated to a 1-μm In bump), we measured a minimum T c of 3.14 K at a bias current of 3 mA and a normal resistance of 0.59 mΩ per interconnect. We also investigated the design and fabrication of superconducting niobium (Nb) microstrip atop flexible polyimide. We present a process for integrating In bumps with the flexible Nb leads to enable high-density wiring for the ATHENA X-IFU focal plane.
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Affiliation(s)
- N. S. DeNigris
- NASA GSFC, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
| | | | - S. R. Bandler
- NASA GSFC, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
| | - M. P. Chang
- Stinger Ghaffarian Technologies, 7515 Mission Drive, Suite 300, Seabrook, MD 20706, USA
| | - N. P. Costen
- Stinger Ghaffarian Technologies, 7515 Mission Drive, Suite 300, Seabrook, MD 20706, USA
| | - M. E. Eckart
- NASA GSFC, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
| | - J. Y. Ha
- SB Microsystems, 806 Cromwell Park Drive, Glen Burnie, MD 21061, USA
| | | | - S. J. Smith
- University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
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6
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Zhou Y, Ambarish CV, Gruenke R, Jaeckel FT, Kripps KL, McCammon D, Morgan KM, Wulf D, Zhang S, Adams JS, Bandler SR, Chervenak JA, Datesman AM, Eckart ME, Ewin AJ, Finkbeiner FM, Kelley RL, Kilbourne CA, Miniussi AR, Porter FS, Sadleir JE, Sakai K, Smith SJ, Wakeham NA, Wassell EJ, Yoon W. Mapping TES Temperature Sensitivity and Current Sensitivity as a Function of Temperature, Current, and Magnetic Field with IV curve and Complex Admittance Measurements. J Low Temp Phys 2018; 193:321-327. [PMID: 31186584 PMCID: PMC6557576 DOI: 10.1007/s10909-018-1970-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 05/14/2018] [Indexed: 06/09/2023]
Abstract
We have specialized astronomical applications for X-ray microcalorimeters with superconducting transition edge sensors (TESs) that require exceptionally good TES performance, but which operate in the small-signal regime. We have therefore begun a program to carefully characterize the entire transition surface of TESs with and without the usual zebra stripes to see if there are reproducible local "sweet spots" where the performance is much better than average. These measurements require precise knowledge of the circuit parameters. Here, we show how the Shapiro effect can be used to precisely calibrate the value of the shunt-resistor. We are also investigating the effects of stress and external magnetic fields to better understand reproducibility problems.
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Affiliation(s)
- Y Zhou
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - C V Ambarish
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - R Gruenke
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - F T Jaeckel
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - K L Kripps
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - D McCammon
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - K M Morgan
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - D Wulf
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - S Zhang
- Physics Department, University of Wisconsin - Madison, Madison, WI, USA
| | - J S Adams
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - S R Bandler
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J A Chervenak
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - A M Datesman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - M E Eckart
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - A J Ewin
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | - R L Kelley
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - C A Kilbourne
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - A R Miniussi
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - F S Porter
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J E Sadleir
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - K Sakai
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - S J Smith
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - N A Wakeham
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - E J Wassell
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W Yoon
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
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7
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Wassell EJ, Adams JS, Bandler SR, Betancourt-Martinez GL, Chiao MP, Chang MP, Chervenak JA, Datesman AM, Eckart ME, Ewin AJ, Finkbeiner FM, Ha JY, Kelley R, Kilbourne CA, Miniussi AR, Sakai K, Porter F, Sadleir JE, Smith SJ, Wakeham NA, Yoon W. Fabrication of X-ray Microcalorimeter Focal Planes Composed of Two Distinct Pixel Types. IEEE Trans Appl Supercond 2017; 27:2300205. [PMID: 28804229 PMCID: PMC5548520 DOI: 10.1109/tasc.2016.2633783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We are developing superconducting transition-edge sensor (TES) microcalorimeter focal planes for versatility in meeting specifications of X-ray imaging spectrometers including high count-rate, high energy resolution, and large field-of-view. In particular, a focal plane composed of two sub-arrays: one of fine-pitch, high count-rate devices and the other of slower, larger pixels with similar energy resolution, offers promise for the next generation of astrophysics instruments, such as the X-ray Integral Field Unit (X-IFU) instrument on the European Space Agency's Athena mission. We have based the sub-arrays of our current design on successful pixel designs that have been demonstrated separately. Pixels with an all gold X-ray absorber on 50 and 75 micron scales where the Mo/Au TES sits atop a thick metal heatsinking layer have shown high resolution and can accommodate high count-rates. The demonstrated larger pixels use a silicon nitride membrane for thermal isolation, thinner Au and an added bismuth layer in a 250 micron square absorber. To tune the parameters of each sub-array requires merging the fabrication processes of the two detector types. We present the fabrication process for dual production of different X-ray absorbers on the same substrate, thick Au on the small pixels and thinner Au with a Bi capping layer on the larger pixels to tune their heat capacities. The process requires multiple electroplating and etching steps, but the absorbers are defined in a single ion milling step. We demonstrate methods for integrating heatsinking of the two types of pixel into the same focal plane consistent with the requirements for each sub-array, including the limiting of thermal crosstalk. We also discuss fabrication process modifications for tuning the intrinsic transition temperature (Tc) of the bilayers for the different device types through variation of the bilayer thicknesses. The latest results on these "hybrid" arrays will be presented.
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Affiliation(s)
- E J Wassell
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. Stinger-Ghaffarian Technologies, Inc., Greenbelt, MD 20771 USA
| | - J S Adams
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. CRESST, University of Maryland, College Park, MD 20742 USA
| | - S R Bandler
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - G L Betancourt-Martinez
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. University of Maryland, College Park, MD 20742 USA
| | - M P Chiao
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - M P Chang
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - J A Chervenak
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - A M Datesman
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. Stinger-Ghaffarian Technologies, Inc., Greenbelt, MD 20771 USA
| | - M E Eckart
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - A J Ewin
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - F M Finkbeiner
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. Wyle Information Systems, McLean, VA 22102 USA
| | - J Y Ha
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. SB Microsystems Inc., Glen Burnie, MD 20161 USA
| | - R Kelley
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - C A Kilbourne
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - A R Miniussi
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - K Sakai
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. Universities Space Research Association, MD, USA
| | - F Porter
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - J E Sadleir
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - S J Smith
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. CRESST, University of Maryland, College Park, MD 20742 USA
| | - N A Wakeham
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. Universities Space Research Association, MD, USA
| | - W Yoon
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA. Universities Space Research Association, MD, USA
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8
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Eckart ME, Boyce KR, Brown GV, Chiao MP, Fujimoto R, Haas D, den Herder JW, Ishisaki Y, Kelley RL, Kilbourne CA, Leutenegger MA, McCammon D, Mitsuda K, Porter FS, Sawada M, Sneiderman GA, Szymkowiak AE, Takei Y, Tashiro M, Tsujimoto M, de Vries CP, Watanabe T, Yamada S, Yamasaki NY. Calibration of the microcalorimeter spectrometer on-board the Hitomi (Astro-H) observatory (invited). Rev Sci Instrum 2016; 87:11D503. [PMID: 27910640 DOI: 10.1063/1.4961075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The Hitomi Soft X-ray Spectrometer (SXS) was a pioneering non-dispersive imaging x-ray spectrometer with 5 eV FWHM energy resolution, consisting of an array of 36 silicon-thermistor microcalorimeters at the focus of a high-throughput soft x-ray telescope. The instrument enabled astrophysical plasma diagnostics in the 0.3-12 keV band. We introduce the SXS calibration strategy and corresponding ground calibration measurements that took place from 2012-2015, including both the characterization of the microcalorimeter array and measurements of the x-ray transmission of optical blocking filters.
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Affiliation(s)
- M E Eckart
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - K R Boyce
- NASA Goddard Space Flight Center, Code 592, Greenbelt, Maryland 20771, USA
| | - G V Brown
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - M P Chiao
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - R Fujimoto
- Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - D Haas
- SRON Netherlands Institute for Space Research, Utrecht, The Netherlands
| | - J-W den Herder
- SRON Netherlands Institute for Space Research, Utrecht, The Netherlands
| | - Y Ishisaki
- Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - R L Kelley
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - C A Kilbourne
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - M A Leutenegger
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - D McCammon
- University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - K Mitsuda
- Institute of Space and Astronautical Science, JAXA, Sagamihara, Kanagawa 252-5210, Japan
| | - F S Porter
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - M Sawada
- Aoyama Gakuin University, Sagamihara, Kanagawa 252-5258, Japan
| | - G A Sneiderman
- NASA Goddard Space Flight Center, Code 592, Greenbelt, Maryland 20771, USA
| | | | - Y Takei
- Institute of Space and Astronautical Science, JAXA, Sagamihara, Kanagawa 252-5210, Japan
| | - M Tashiro
- Saitama University, Sakura-ku, Saitama 338-8570, Japan
| | - M Tsujimoto
- Institute of Space and Astronautical Science, JAXA, Sagamihara, Kanagawa 252-5210, Japan
| | - C P de Vries
- SRON Netherlands Institute for Space Research, Utrecht, The Netherlands
| | - T Watanabe
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - S Yamada
- Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - N Y Yamasaki
- Institute of Space and Astronautical Science, JAXA, Sagamihara, Kanagawa 252-5210, Japan
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9
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Leutenegger MA, Beiersdorfer P, Betancourt-Martinez GL, Brown GV, Hell N, Kelley RL, Kilbourne CA, Magee EW, Porter FS. Characterization of an atomic hydrogen source for charge exchange experiments. Rev Sci Instrum 2016; 87:11E516. [PMID: 27910505 DOI: 10.1063/1.4959919] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We characterized the dissociation fraction of a thermal dissociation atomic hydrogen source by injecting the mixed atomic and molecular output of the source into an electron beam ion trap containing highly charged ions and recording the x-ray spectrum generated by charge exchange using a high-resolution x-ray calorimeter spectrometer. We exploit the fact that the charge exchange state-selective capture cross sections are very different for atomic and molecular hydrogen incident on the same ions, enabling a clear spectroscopic diagnostic of the neutral species.
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Affiliation(s)
- M A Leutenegger
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - P Beiersdorfer
- Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550, USA
| | | | - G V Brown
- Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550, USA
| | - N Hell
- Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550, USA
| | - R L Kelley
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - C A Kilbourne
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
| | - E W Magee
- Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550, USA
| | - F S Porter
- NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771, USA
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10
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Beiersdorfer P, Brown GV, Graf AT, Bitter M, Hill KW, Kelley RL, Kilbourne CA, Leutenegger MA, Porter FS. Rest-wavelength fiducials for the ITER core imaging x-ray spectrometer. Rev Sci Instrum 2012; 83:10E111. [PMID: 23126933 DOI: 10.1063/1.4733318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Absolute wavelength references are needed to derive the plasma velocities from the Doppler shift of a given line emitted by a moving plasma. We show that such reference standards exist for the strongest x-ray line in neonlike W(64+), which has become the line of choice for the ITER (Latin "the way") core imaging x-ray spectrometer. Close-by standards are the Hf Lβ(3) line and the Ir Lα(2) line, which bracket the W(64+) line by ±30 eV; other standards are given by the Ir Lα(1) and Lα(2) lines and the Hf Lβ(1) and Lβ(2) lines, which bracket the W(64+) line by ±40 and ±160 eV, respectively. The reference standards can be produced by an x-ray tube built into the ITER spectrometer. We present spectra of the reference lines obtained with an x-ray microcalorimeter and compare them to spectra of the W(64+) line obtained both with an x-ray microcalorimeter and a crystal spectrometer.
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Affiliation(s)
- P Beiersdorfer
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
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11
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Magee EW, Dunn J, Brown GV, Cone KV, Park J, Porter FS, Kilbourne CA, Kelley RL, Beiersdorfer P. Calibration of a high resolution grating soft x-ray spectrometer. Rev Sci Instrum 2010; 81:10E314. [PMID: 21034013 DOI: 10.1063/1.3494276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The calibration of the soft x-ray spectral response of a large radius of curvature, high resolution grating spectrometer (HRGS) with a back-illuminated charge-coupled device detector is reported. The instrument is cross-calibrated for the 10-50 Å waveband at the Lawrence Livermore National Laboratory electron beam ion trap (EBIT) x-ray source with the EBIT calorimeter spectrometer. The HRGS instrument is designed for laser-produced plasma experiments and is important for making high dynamic range measurements of line intensities, line shapes, and x-ray sources.
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Affiliation(s)
- E W Magee
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550, USA
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12
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Beiersdorfer P, Brown GV, Clementson J, Dunn J, Morris K, Wang E, Kelley RL, Kilbourne CA, Porter FS, Bitter M, Feder R, Hill KW, Johnson D, Barnsley R. The ITER core imaging x-ray spectrometer: x-ray calorimeter performance. Rev Sci Instrum 2010; 81:10E323. [PMID: 21034021 DOI: 10.1063/1.3495789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We describe the anticipated performance of an x-ray microcalorimeter instrument on ITER. As part of the core imaging x-ray spectrometer, the instrument will augment the imaging crystal spectrometers by providing a survey of the concentration of heavy ion plasma impurities in the core and possibly ion temperature values from the emission lines of different elemental ions located at various radial positions.
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Affiliation(s)
- P Beiersdorfer
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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13
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Park J, Brown GV, Schneider MB, Baldis HA, Beiersdorfer P, Cone KV, Kelley RL, Kilbourne CA, Magee EW, May MJ, Porter FS. Calibration of a flat field soft x-ray grating spectrometer for laser produced plasmas. Rev Sci Instrum 2010; 81:10E319. [PMID: 21034017 DOI: 10.1063/1.3495790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We have calibrated the x-ray response of a variable line spaced grating spectrometer, known as the VSG, at the Fusion and Astrophysics Data and Diagnostic Calibration Facility at the Lawrence Livermore National Laboratory (LLNL). The VSG has been developed to diagnose laser produced plasmas, such as those created at the Jupiter Laser Facility and the National Ignition Facility at LLNL and at both the Omega and Omega EP lasers at the University of Rochester's Laboratory for Laser Energetics. The bandwidth of the VSG spans the range of ∼6-60 Å. The calibration results presented here include the VSG's dispersion and quantum efficiency. The dispersion is determined by measuring the x rays emitted from the hydrogenlike and heliumlike ions of carbon, nitrogen, oxygen, neon, and aluminum. The quantum efficiency is calibrated to an accuracy of 30% or better by normalizing the x-ray intensities recorded by the VSG to those simultaneously recorded by an x-ray microcalorimeter spectrometer.
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Affiliation(s)
- J Park
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808, USA.
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14
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Leutenegger MA, Beiersdorfer P, Brown GV, Kelley RL, Kilbourne CA, Porter FS. Measurement of anomalously strong emission from the 1s-9p transition in the spectrum of H-like phosphorus following charge exchange with molecular hydrogen. Phys Rev Lett 2010; 105:063201. [PMID: 20867978 DOI: 10.1103/physrevlett.105.063201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 06/10/2010] [Indexed: 05/29/2023]
Abstract
We have measured K-shell x-ray spectra of highly ionized argon and phosphorus following charge exchange with molecular hydrogen at low collision energy in an electron beam ion trap using an x-ray calorimeter array with ∼6 eV resolution. We find that the emission at the high end of the Lyman series is greater by a factor of 2 for phosphorus than for argon, even though the measurement was performed concurrently and the atomic numbers are similar. This does not agree with current theoretical models and deviates from the trend observed in previous measurements.
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Affiliation(s)
- M A Leutenegger
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
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15
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Porter FS, Beiersdorfer P, Brown GV, Gu MF, Kelley RL, Kahn S, Kilbourne CA, Thorn DB. Evolution of X-ray calorimeter spectrometers at the Lawrence Livermore Electron Beam Ion Trap. ACTA ACUST UNITED AC 2009. [DOI: 10.1088/1742-6596/163/1/012105] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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16
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Brown GV, Beiersdorfer P, Emig J, Frankel M, Gu MF, Heeter RF, Magee E, Thorn DB, Widmann K, Kelley RL, Kilbourne CA, Porter FS. Rapid, absolute calibration of x-ray filters employed by laser-produced plasma diagnostics. Rev Sci Instrum 2008; 79:10E309. [PMID: 19044471 DOI: 10.1063/1.2965214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The Electron Beam Ion Trap (EBIT) facility at the Lawrence Livermore National Laboratory is being used to absolutely calibrate the transmission efficiency of x-ray filters employed by diodes and spectrometers used to diagnose laser-produced plasmas. EBIT emits strong, discrete monoenergetic lines at appropriately chosen x-ray energies. X rays are detected using the high resolution EBIT Calorimeter Spectrometer (ECS), developed for LLNL at the NASA/Goddard Space Flight Center. X-ray filter transmission efficiency is determined by dividing the x-ray counts detected when the filter is in the line of sight by those detected when out of the line of sight. Verification of filter thickness can be completed in only a few hours, and absolute efficiencies can be calibrated in a single day over a broad range from about 0.1 to 15 keV. The EBIT calibration lab has been used to field diagnostics (e.g., the OZSPEC instrument) with fully calibrated x-ray filters at the OMEGA laser. Extensions to use the capability for calibrating filter transmission for the DANTE instrument on the National Ignition Facility are discussed.
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Affiliation(s)
- G V Brown
- Department of Physical Sciences, High Energy Density Physics and Astrophysics Division, Lawrence Livermore National Laboratory, 7000 East Avenue, L-260, Livermore, California 94550, USA
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17
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Beck BR, Becker JA, Beiersdorfer P, Brown GV, Moody KJ, Wilhelmy JB, Porter FS, Kilbourne CA, Kelley RL. Energy splitting of the ground-state doublet in the nucleus 229Th. Phys Rev Lett 2007; 98:142501. [PMID: 17501268 DOI: 10.1103/physrevlett.98.142501] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2006] [Indexed: 05/15/2023]
Abstract
The energy splitting of the 229Th ground-state doublet is measured to be 7.6+/-0.5 eV, significantly greater than earlier measurements. Gamma rays produced following the alpha decay of 233U (105 muCi) were counted in the NASA/electron beam ion trap x-ray microcalorimeter spectrometer with an experimental energy resolution of 26 eV (FWHM). A difference technique was applied to the gamma-ray decay of the 71.82 keV level that populates both members of the doublet. A positive correction amounting to 0.6 eV was made for the unobserved interband decay of the 29.19 keV state (29.19-->0 keV).
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Affiliation(s)
- B R Beck
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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18
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Brown GV, Beiersdorfer P, Chen H, Scofield JH, Boyce KR, Kelley RL, Kilbourne CA, Porter FS, Gu MF, Kahn SM, Szymkowiak AE. Energy-dependent excitation cross section measurements of the diagnostic lines of Fe XVII. Phys Rev Lett 2006; 96:253201. [PMID: 16907303 DOI: 10.1103/physrevlett.96.253201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Indexed: 05/11/2023]
Abstract
By implementing a large-area, gain-stabilized microcalorimeter array on an electron beam ion trap, the electron-impact excitation cross sections for the dominant x-ray lines in the Fe XVII spectrum have been measured as a function of electron energy establishing a benchmark for atomic calculations. The results show that the calculations consistently predict the cross section of the resonance line to be significantly larger than measured. The lower cross section accounts for several problems found when modeling solar and astrophysical Fe XVII spectra.
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Affiliation(s)
- G V Brown
- University of California Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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