Abstract：
:Direct comparisons of the National Institute of Standards and Technology's (NIST) Ritz 20 kV to 100 kV standard free-air ionization chamber and a portable variable-length free-air ionization chamber designed by the University of Wisconsin-Madison Accredited Dosimetry Calibration Laboratory (UW-ADCL) were made on NISTs low-energy tungsten x-ray range. As a result of this direct comparison, NIST has established a UW-ADCL designed chamber, the Attix chamber, as the national standard chamber for the mammography energy x-ray range. The Ritz standard chamber and the Attix standard chamber have been extensively compared using the new molybdenum and rhodium beam qualities. The results indicate that exposure measurements in the mammography energy x-ray region with the two free-air chambers can be made with a discrepancy of less than 0.35%.
journal_name
Med Physjournal_title
Medical physicsauthors
Coletti JG,Pearson DW,DeWerd LA,O'Brien CM,Lamperti PJdoi
10.1118/1.598148subject
Has Abstractpub_date
1997-08-01 00:00:00pages
1263-7issue
8eissn
0094-2405issn
2473-4209journal_volume
24pub_type
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