The Decay ofI125

Abstract

The decay of l m has been investigated. The nuclide decays entirely by orbital electron capture with a half-life of 60.0=fc0.5 days. An upper limit of 5X10" 4 was set for the fraction of l m decaying to the 58-day isomer of Te 125 . By proportional counter and coincidence measurements it was established that all transitions go to the 35.4-kev level of Te 125 , which is a dm state. The I 125 ground state can be assigned a J5/2 configuration. The ratio of L\ to K electron capture was determined to be between 0.18 and 0.45, with a most probable value 0.30. From these ratios, the energy difference between the ground states of I 125 and Te 128 was found to be between 95 and 215 kev, with the most probable value 115 kev. The corresponding// values for the transition to the 35.4-kev level of Te 125 fall in the range of allowed transitions.

Study of the Relationship Between Plasma Volume and Transcapillary Protein Exchange Using I 131 -Labeled Albumin and I 125 -Labeled Globulin

“…17 This may also bo construed as evidence that there was no contaminating radioactivity from other sources in the I 13 at the time the material was analyzed.…”

“…I 1 -"' has a half-life of 60 days and emits a 27 kev x-ray and a 35.4 kev gamma ray. 1 "'" 17 The I 1 -'"' used in the present studies was prepared in the cyclotron at the Oak Ridge National Laboratory. Significant quantities (10-12 per cent) of I 1 -0 were also produced by this method.…”

Iodine-125, a tracer in cell biology: physical properties and biological aspects

“…The decay proceeds in two steps (Friedlander and Orr 1951, Lentz and Ziegler 1964, Richmond and Findlay 1966, Lederer, Hollander and Perlman…”

“…The physical data of the decay of iodine-125 have been investigated by several authors (Friedlander and Orr 1951, Bergstrom 1951, Bowe and Axel 1952, Myers and Vanderleeden 1960, Dillman 1966. Their results will be summarized, evaluated and extended with respect to microdosimetry.…”