Abstract:
:A double-mirror multilayer monochromator was developed for the purpose of irradiating live cell cultures at the Synchrotron Radiation Center, University of Wisconsin-Madison. The monochromator is designed for the soft x-ray region with photon energies between 270 and 2400 eV. Multilayer mirrors with 55 bilayers of W/C and a bilayer spacing of d = 3.0 nm are sputter deposited on Si substrates. By proper masking of the sputtering sources, variation in the bilayer spacing over the area of the mirror is minimized. The uniformity of the bilayer spacing was measured to be delta d/d < 1%, over the 75 mm x 25 mm area of the mirrors. The reflectivity was measured as a function of energy to determine the integrated reflectivity and evaluate the contribution of the specular reflection and higher orders to the monochromatic beam. The use of suitable filters with a Si(Li) detector allows determination of the spectral output of the monochromator. The output power of the monochromator between 270 and 2400 eV is measured. The resolution of the monochromator is delta lambda/lambda = 0.04. Applications of the monochromator to radiation biology are discussed.
journal_name
Med Physjournal_title
Medical physicsauthors
MacKay JF,Pearson DW,Nelms BE,DeLuca PM Jr,Gould MN,Lagally MGdoi
10.1118/1.598259subject
Has Abstractpub_date
1998-05-01 00:00:00pages
773-9issue
5eissn
0094-2405issn
2473-4209journal_volume
25pub_type
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