Ortho-para spin conversion of Ps by paramagnetic O2 dissolved in organic compounds

• Autorzy: Zgardzińska B. , Białko W. , Jasińska B.

Identyfikatory

DOI

10.1515/nuka-2015-0144

• Konferencja: Polish Seminar on Positron Annihilation (42 nd ; 29.06-01.07.2016 ; Lublin, Poland)
• Języki publikacji: EN

Abstrakty

EN

The o-Ps mean lifetime value in liquids decreases in the presence of the paramagnetic oxygen molecules via the ortho-para conversion process. This effect was observed for several organic samples composed of carbon and hydrogen atoms differing in the arrangement of atoms forming the molecule, e.g. n-alkanes, alcohols, branched isomer of alkane, cycloalkane. The usually observed tendency of the o-Ps lifetime value to be an increasing function of temperature (in the case of measurements performed in vacuum) changes to a decreasing one in the presence of O2 dissolved in the sample. The difference between the o-Ps lifetimes measured in samples in vacuum and in the presence of O2 increases with the distance from the melting point. The ortho-para constant rate λconv was estimated to be ~130 μs–1 at 300 K for three compounds investigated.

Słowa kluczowe

EN

alcohols; cyclohexane; isooctane; n-alkanes; ortho-para conversion; paramagnetic molecule

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2015
• Tom: Vol. 60, No. 4, part 1
• Strony: 801--804
• Opis fizyczny: Bibliogr. 10 poz., rys.

Twórcy

autor

Zgardzińska B.

• Department of Nuclear Methods, Institute of Physics, Maria Curie-Sklodowska University, 1 M. Curie-Sklodowskiej Sq., 20-031 Lublin, Poland, Tel.: [phone], Fax: [phone]

autor

Białko W.

• Department of Nuclear Methods, Institute of Physics, Maria Curie-Sklodowska University, 1 M. Curie-Sklodowskiej Sq., 20-031 Lublin, Poland, Tel.: [phone], Fax: [phone]

autor

Jasińska B.

• Department of Nuclear Methods, Institute of Physics, Maria Curie-Sklodowska University, 1 M. Curie-Sklodowskiej Sq., 20-031 Lublin, Poland, Tel.: [phone], Fax: [phone]

Bibliografia

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