Vol. 12, no.1, 2020


Dissolved oxygen and positronium atom in liquid media

Sergey V. Stepanov, Alexander V. Bokov, OlgaV. Ilyukhina, Vsevolod M. Byakov

National Research Centre "Kurchatov Institute" - ITEP, http://www.itep.ru/
Moscow 117218, Russian Federation
E-mail: stepanov@itep.ru, av.bokov@yandex.ru, ilyukhina@itep.ru, byakov@itep.ru

Received February 06, 2020; peer reviewed February 14, 2020; accepted February 18, 2020
Abstract. The interaction of positronium (Ps) with molecular oxygen dissolved in liquids (isooctane, cyclohexane, isopropanol and water) is experimentally investigated. For variation of the O2 concentration the liquids were bubbled with Ar, air and O2. For interpretation of the lifetime annihilation spectra a simple deconvolution of the spectra into three exponentials decaying in time was used. These exponents correspond to para-positronium, free positron and ortho-positronium annihilations. The total reaction rate constant of the Ps atom with dissolved oxygen (which is the sum of two - ortho-para-conversion (Ps → ¼ p-Ps + ¾ o-Ps) and oxidation (Ps + O2 → e+ + O2–) reaction rate constants) is obtained for each liquid

Keywords: positron, annihilation, oxidation, ortho-para conversion, oxygen, track processes

UDC 539.124.6+541.6

RENSIT, 2020, 12(1):107-114. DOI: 10.17725/rensit.2020.12.107.

Full-text electronic version of this article - web site http://en.rensit.ru/vypuski/article/312/12(1)107-114e.pdf