The RAD-7 is a radon-in-air monitor containing an inside vacuum pump associated with an alpha semiconductor detector that employs energy discrimination to count the daughters of radon 222 and thoron (radon-220
).This tool has widely been used in the recent water studies; (Abojassim et al., 2017; Al-Hamidawi, 2015).
Thorium is a naturally occurring radioactive chemical element which produces a radioactive gas, radon-220
For the new study, physicist Peter Butler of the University of Liverpool in England and an international team probed two potentially pear-shaped nuclei: radon-220, which is made up of 86 protons and 134 neutrons, and radium-224, with 88 protons and 136 neutrons.
The high-energy protons shattered the atoms in the block, producing a cornucopia of exotic atoms that included radon-220 and radium-224.
The radiation showed that both radon-220 and radium-224 nuclei have an asymmetric pear shape.
Reports in the June HEALTH PHYSICS highlight two such features: the presence of radon-220 and the fraction of daughters that do not cling to dust.
Radon-220 is a fifth-generation daughter of thrium-232, and radon-222 is a sixth-generation descendant of uranium-238.
Radon-220's fleeting nature explains why most current radon monitoring ignores it, says Dowell E.
Using the known characteristic alpha energy of each radon daughter, they established that roughly one-quarter of the alpha radiation in the buildings' air had been emitted by daughters of radon-220.
, the isotope emitted by thorium, wasn't detected outside display cases of throium-rich minerals -- perhaps Crameri says, because this isotope decayed before it could leak out.