Positrons in naphthalene : critical remarks on the relation between o-Ps lifetime and void size

• Autorzy: Goworek T. , Zgardzińska B. , Wawryszczuk J.
• Konferencja: Proceedings of the 40th Polish Seminar on Positron Annihilation PSPA'2012, 13-14 June 2012, Kazimierz Dolny, Poland
• Języki publikacji: EN

Abstrakty

EN

Lowering the temperature or applying high pressure leads to elimination of positronium component in the e+ lifetime spectrum in solid naphthalene. Disappearance of positronium means reaching the free volume size limit at which there is no energy level in the potential well. It allows to estimate that size, which is found inconsistent with predictions of the popular Tao-Eldrup model. The range of applicability of that model is discussed. The dependence of the free e+ decay constant on pressure indicates that positronium is formed not only in the blob processes, but during the whole free positron life. The lifetime of free positrons begins to rise with temperature earlier than Ps intensity.

Słowa kluczowe

EN

high pressure; naphthalene; positronium quenching; free volume

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2013
• Tom: Vol. 58, No. 1
• Strony: 183--187
• Opis fizyczny: BIbliogr. 24 poz., rys.

Twórcy

autor

Goworek T.

autor

Zgardzińska B.

autor

Wawryszczuk J.

• Maria Curie-Skłodowska University, Institute of Physics, 1 M. Curie-Skłodowskiej Sq., 20-031 Lublin, Poland, Tel.: [phone], Fax: [phone],,

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