title: The cosmic ray actinide charge spectrum derived from a 10 m2 array of solid state nuclear track detectors in Earth orbit.
abstract: The DIAS-ESTEC Ultra Heavy Cosmic Ray Experiment (UHCRE) on the Long Duration Exposure Facility, collected approximately 3000 cosmic ray nuclei with Z > 65 in the energy region E > 1.5 GeV nucleon-1 during a six year exposure in Earth orbit. The entire accessible collecting area of the solid state nuclear track detector (SSNTD) array has been scanned for actinides, yielding a sample of 30 from an exposure of approximately 150 m2 sr yr. The UHCRE experimental setup is described and the observed charge spectrum presented. The current best value for the cosmic ray actinide relative abundance, (Z > 88)/(74 < or = Z < or = 87), is reported.
authors.affiliation: Dublin Institute for Advanced Studies (DIAS), 5 Merrion Square, Dublin 2, Ireland. jd@cp.dias.ie
authors.forename: J
authors.initials: J
authors.lastname: Donnelly
authors.forename: A
authors.initials: A
authors.lastname: Thompson
authors.forename: D
authors.initials: D
authors.lastname: O'Sullivan
authors.forename: L O
authors.initials: LO
authors.lastname: Drury
authors.forename: K P
authors.initials: KP
authors.lastname: Wenzel
mesh_terms: D008671:Actinoid Series Elements / Q000032:analysis*; D002138:Calibration; D003359:Cosmic Radiation; D005118:Extraterrestrial Environment; D011108:Polymers; D011834:Radiation Monitoring / Q000295:instrumentation*; D011874:Radiometry; D013026:Space Flight / Q000295:instrumentation*; D018531:Spacecraft / Q000295:instrumentation*
chemical_list: D008671:Actinoid Series Elements; D011108:Polymers; C017902:lexan