An evaluation of multilayer mirrors for the soft x ray and extreme ultraviolet wavelength range that were irradiated with neutrons

Journal Article · Wed Jan 01 04:00:00 EST 1997 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1148449· OSTI ID:451870

Regan, S P; May, M J; Soukhanovskii, V; Finkenthal, M; Moos, H W ^[1]; Farnum, E H; Clinard, Jr, F W ^[2]; Tarrio, C; Watts, R ^[3]

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1. The Plasma Spectroscopy Group, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218 (United States)
2. Los Alamos National Laboratory, Los Alamos, New Mexico (United States)
3. National Institute of Standards and Technology, Gaithersburg, Maryland (United States)

The Plasma Spectroscopy Group at the Johns Hopkins University develops high photon throughput multilayer mirror (MLM) based soft x ray and extreme ultraviolet (XUV 10 {Angstrom}{lt}{lambda}{lt}304 {Angstrom}) spectroscopic diagnostics for magnetically confined fusion plasmas. The D-T reactions in large fusion reactor type devices such as the International Thermonuclear Experimental Reactor will produce neutrons at a rate as high as 5{times}10{sup 19} ns{sup -1}. The MLMs, which are used as dispersive and focusing optics, will not be shielded from these neutrons. In an effort to assess the potential radiation damage, four MLMs (No. 1: Mo/Si, d=87.8 {Angstrom}, Zerodur substrate with 50 cm concave spherical curvature; No. 2: W/B{sub 4}C, d=22.75 {Angstrom}, Si wafer substrate; No. 3: W/C, d=25.3 {Angstrom}, Si wafer substrate; and No. 4: Mo/Si, d=186.6 {Angstrom}, Si wafer substrate) were irradiated with fast neutrons at the Los Alamos Spallation Radiation Effects Facility (LASREF). The neutron beam at LASREF has an energy distribution that peaks at 1{endash}2 MeV with a tail that extends out to 100 MeV. The MLMs were irradiated to a fast neutron fluence of 1.1{times}10{sup 19} ncm{sup {minus}2} at 270{endash}300{degree}C. A comparison between the dispersive and reflective characteristics of the irradiated MLMs and the corresponding qualities of control samples will be given. {copyright} {ital 1997 American Institute of Physics.}

• OSTI ID: 451870
• Report Number(s): CONF-960543--
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 1 Vol. 68; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
COMPARATIVE EVALUATIONS
D-T REACTORS
DAMAGE
EXTREME ULTRAVIOLET RADIATION
MAGNETIC CONFINEMENT
MEV RANGE
MIRRORS
NEUTRON BEAMS
OPTICAL SYSTEMS
PHYSICAL RADIATION EFFECTS
PLASMA DIAGNOSTICS
SOFT X RADIATION
TEMPERATURE RANGE 0400-1000 K
TOKAMAK DEVICES