title: Source self-attenuation in ionization chamber measurements of (57)Co solutions.
abstract: Source self-attenuation for solutions of (57)Co of varying density and carrier concentration was measured in nine re-entrant ionization chambers maintained at NIST. The magnitude of the attenuation must be investigated to determine whether a correction is necessary in the determination of the activity of a source that differs in composition from the source used to calibrate the ionization chamber. At our institute, corrections are currently made in the measurement of (144)Ce, (109)Cd, (67)Ga, (195)Au, (166)Ho, (177)Lu, and (153)Sm. This work presents the methods used as recently applied to (57)Co. A range of corrections up to 1% were calculated for dilute to concentrated HCl at routinely used carrier concentrations.
authors.affiliation: National Institute of Standards and Technology (NIST), 100 Bureau Drive MS8462, Gaithersburg, MD 20899-8462, USA. Electronic address: Jeffrey.Cessna@nist.gov.
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Cessna
authors.affiliation: National Institute of Standards and Technology (NIST), 100 Bureau Drive MS8462, Gaithersburg, MD 20899-8462, USA; Nuclear Energy Institute, 1201 F Street NW, Washington, DC 20004, USA.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Golas
authors.affiliation: National Institute of Standards and Technology (NIST), 100 Bureau Drive MS8462, Gaithersburg, MD 20899-8462, USA.
authors.forename: Denis E
authors.initials: DE
authors.lastname: Bergeron
keywords: (57)Co solution; Ionization chamber; Self-attenuation