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Da Ros A, Vezinet D, Colledani G, Fenzi-Bonizec C, Moureau G, Bertschinger G. Electron and ion temperature measurement with a new x-ray imaging crystal spectrometer on WEST. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:043505. [PMID: 38587445 DOI: 10.1063/5.0179905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 03/21/2024] [Indexed: 04/09/2024]
Abstract
A new x-ray imaging crystal spectrometer (XICS) has been installed, aligned, and used during experimental campaigns on the WEST tokamak. It has three interchangeable crystals for measuring the Ar XVII, Ar XVIII, and Fe XXV spectra, respectively. A patented rotating table holding the crystals is used to monitor the crystal facing the plasma remotely and without changing the position of the camera. Here, the focus is made on the Ar XVII spectrum, between 3.93 and 4.00 Å. The design of the diagnostic is presented, and a synthetic diagnostic, implemented with the Python library ToFu, is used to show the instrument's operational performance and limits. The instrument function exhibits the following two main features: a distortion for the Ar XVII spectrum, presumably due to the crystal manufacturing in two parts, and the measurement of three W spectral lines on the Ar XVI spectrum. Line of sight-integrated profiles of the electron and ion temperatures are thus extracted from the Ar XVII spectrum from two distinct spectral line ratios and from the Doppler broadening, respectively. The bremsstrahlung emission and the W line measurements are the two main limitations to compute the electron temperature. Tomographic inversions are also implemented with the library ToFu and used in order to obtain the local electron and ion temperature profiles, which are compared to other measurements from the WEST ECE (electron cyclotron emission) diagnostic. It is shown that both the XICS line-integrated and ECE Te measurements are in better agreement. Systematic differences are shown between the electron temperature profiles calculated from the two available line ratios.
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Affiliation(s)
- A Da Ros
- CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
| | - D Vezinet
- CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
| | - G Colledani
- CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
| | | | - G Moureau
- CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
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Gall AC, Foster AR, Silwal R, Dreiling JM, Borovik A, Kilgore E, Ajello M, Gillaspy JD, Ralchenko Y, Takács E. EBIT Observation of Ar Dielectronic Recombination Lines near the Unknown Faint X-Ray Feature Found in the Stacked Spectrum of Galaxy Clusters. THE ASTROPHYSICAL JOURNAL 2019; 872:10.3847/1538-4357/ab0177. [PMID: 34795454 PMCID: PMC8596318 DOI: 10.3847/1538-4357/ab0177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Motivated by possible atomic origins of the unidentified emission line detected at 3.55-3.57 keV in a stacked spectrum of galaxy clusters, an electron beam ion trap (EBIT) was used to investigate the resonant dielectronic recombination (DR) process in highly charged argon ions as a possible contributor to the emission feature. The He-like Ar DR-induced transition 1s22l-1s2l3l' was suggested to produce a 3.62 keV photon near the unidentified line at 3.57 keV and was the starting point of our investigation. The collisional-radiative model NOMAD was used to create synthetic spectra for comparison with both our EBIT measurements and with spectra produced with the AtomDB database/Astrophysical Plasma Emission Code (APEC) used in the Bulbul et al. work. Excellent agreement was found between the NOMAD and EBIT spectra, providing a high level of confidence in the atomic data used. Comparison of the NOMAD and APEC spectra revealed a number of missing features in the AtomDB database near the unidentified line. At an electron temperature of T e = 1.72 keV, the inclusion of the missing lines in AtomDB increases the total flux in the 3.5-3.66 keV energy band by a factor of 2. While important, this extra emission is not enough to explain the unidentified line found in the galaxy cluster spectra.
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Affiliation(s)
- Amy C Gall
- Clemson University, Department of Physics and Astronomy, Clemson, SC 29634-0978, USA
| | - Adam R Foster
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
| | - Roshani Silwal
- Clemson University, Department of Physics and Astronomy, Clemson, SC 29634-0978, USA
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Joan M Dreiling
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Alexander Borovik
- I. Physikalisches Institut, Justus-Liebig-Universität Gießen, D-35392 Giessen, Germany
| | - Ethan Kilgore
- Clemson University, Department of Physics and Astronomy, Clemson, SC 29634-0978, USA
| | - Marco Ajello
- Clemson University, Department of Physics and Astronomy, Clemson, SC 29634-0978, USA
| | - John D Gillaspy
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
- National Science Foundation, Alexandria, VA 22314, USA
| | - Yuri Ralchenko
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Endre Takács
- Clemson University, Department of Physics and Astronomy, Clemson, SC 29634-0978, USA
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
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Blessenohl MA, Dobrodey S, Warnecke C, Rosner MK, Graham L, Paul S, Baumann TM, Hockenbery Z, Hubele R, Pfeifer T, Ames F, Dilling J, Crespo López-Urrutia JR. An electron beam ion trap and source for re-acceleration of rare-isotope ion beams at TRIUMF. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:052401. [PMID: 29864823 DOI: 10.1063/1.5021045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Electron beam driven ionization can produce highly charged ions (HCIs) in a few well-defined charge states. Ideal conditions for this are maximally focused electron beams and an extremely clean vacuum environment. A cryogenic electron beam ion trap fulfills these prerequisites and delivers very pure HCI beams. The Canadian rare isotope facility with electron beam ion source-electron beam ion sources developed at the Max-Planck-Institut für Kernphysik (MPIK) reaches already for a 5 keV electron beam and a current of 1 A with a density in excess of 5000 A/cm2 by means of a 6 T axial magnetic field. Within the trap, the beam quickly generates a dense HCI population, tightly confined by a space-charge potential of the order of 1 keV times the ionic charge state. Emitting HCI bunches of ≈107 ions at up to 100 Hz repetition rate, the device will charge-breed rare-isotope beams with the mass-over-charge ratio required for re-acceleration at the Advanced Rare IsotopE Laboratory (ARIEL) facility at TRIUMF. We present here its design and results from commissioning runs at MPIK, including X-ray diagnostics of the electron beam and charge-breeding process, as well as ion injection and HCI-extraction measurements.
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Affiliation(s)
- M A Blessenohl
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Dobrodey
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - C Warnecke
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - M K Rosner
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - L Graham
- TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - S Paul
- TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - T M Baumann
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - Z Hockenbery
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - R Hubele
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - T Pfeifer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - F Ames
- TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - J Dilling
- TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
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Stratton BC, Bitter M, Hill KW, Hillis DL, Hogan JT. Chapter 5: Passive Spectroscopic Diagnostics for Magnetically Confined Fusion Plasmas. FUSION SCIENCE AND TECHNOLOGY 2017. [DOI: 10.13182/fst08-a1677] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- B. C. Stratton
- Princeton Plasma Physics Laboratory Princeton University, Princeton, New Jersey 08543
| | - M. Bitter
- Princeton Plasma Physics Laboratory Princeton University, Princeton, New Jersey 08543
| | - K. W. Hill
- Princeton Plasma Physics Laboratory Princeton University, Princeton, New Jersey 08543
| | - D. L. Hillis
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - J. T. Hogan
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
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Fournier KB, Constantin C, Poco J, Miller MC, Back CA, Suter LJ, Satcher J, Davis J, Grun J. Efficient multi-keV X-ray sources from Ti-doped aerogel targets. PHYSICAL REVIEW LETTERS 2004; 92:165005. [PMID: 15169241 DOI: 10.1103/physrevlett.92.165005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2003] [Indexed: 05/24/2023]
Abstract
We have measured the production of hnu approximately 4.7 keV x rays from low-density Ti-doped aerogel (rho approximately 3 mg/cc) targets at the OMEGA laser facility (University of Rochester), with the goal of maximizing x-ray output. Forty OMEGA beams (lambda(L)=0.351 microm) illuminated the two cylindrical faces of the target with a total power that ranged from 7 to 14 TW. The laser fully ionizes the target (n(e)/n(crit)</=0.1), and a laser-bleaching wave excites, supersonically, the high-Z emitter ions in the sample. Ti K-shell x-ray emission was spectrally resolved with a two-channel crystal spectrometer and also with a set of filtered aluminum x-ray diodes; both instruments provide absolute measurement of the multi-keV x-ray emission. We find between 40 and 260 J of output with 4.67</=hnu</=5.0 keV.
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Affiliation(s)
- K B Fournier
- Lawrence Livermore National Laboratory, P.O. Box 808, L-41, Livermore, California 94550, USA
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