title: Experimental investigation of mass efficiency curve for alpha radioactivity counting using a gas-proportional detector.
abstract: Gross alpha counting of evaporated water residues offers a simple method for screening alpha radioactivity in water for both public health and emergency purposes. The evaporation process for water has been improved by using a combination of roughening of the surface of counting planchettes, two-stage evaporation, and temperature-controlled block heating. The efficiency of the gas-proportional detector for alpha-particle detection in water residues was studied as a function of sample mass-thickness in the range between 0.1 and 13 mg cm(-2). The effect of alpha energy on the efficiency, as well as moisture absorption on the samples, were studied using (230)Th, (238)U, (239)Pu, (241)Am, and (244)Cm radionuclides. Also, alpha-to-beta crosstalk was investigated as a function of sample mass for (230)Th, (238)U, (239)Pu, (241)Am, and (244)Cm. The improved method can also be applied for gross alpha detection in biological fluids.
authors.affiliation: New York State Department of Health, Wadsworth Center, Empire State Plaza, Albany, NY 12201-0509, USA. tms15@health.state.ny.us
authors.forename: T M
authors.initials: TM
authors.lastname: Semkow
authors.forename: A
authors.initials: A
authors.lastname: Bari
authors.forename: P P
authors.initials: PP
authors.lastname: Parekh
authors.forename: D K
authors.initials: DK
authors.lastname: Haines
authors.forename: H
authors.initials: H
authors.lastname: Gao
authors.forename: A N
authors.initials: AN
authors.lastname: Bolden
authors.forename: K S
authors.initials: KS
authors.lastname: Dahms
authors.forename: S C
authors.initials: SC
authors.lastname: Scarpitta
authors.forename: R E
authors.initials: RE
authors.lastname: Thern
authors.forename: S
authors.initials: S
authors.lastname: Velazquez