1. POSITRON ANNIIHILATION LIFETIME SPECTROSCOPY Fundamentals and applications Bożena Jasińska Institute of Physics Maria Curie Sklodowska University II SYMPOSIUM ON APPLIED NUCLEAR PHYSICS AND INNOVATIVE TECHNOLOGIES Jagiellonian University, Kraków, September 24 - 27, 2014

2. + _ 511 keV Annihilation

3. outline 1.POSITRON AND POSITRONIUM 2.ETE MODEL 3.EXPERIMENTAL SETUP 4.METALS AND OXIDES 5.PHASE TRANSITION IN POLYMERS 6.POROUS MATERIALS

4. + _ 511 keV Annihilation

5. POSITRONIUM in the vacuum  = 125 ps p-Ps = (7,98950 ± 0,00002) ns -1  = 142 ns o-Ps = (7,03993 ± 0,00001) ms -1 PARAPOSITRONIUM ORTOPOSITRONIUM

6. POSITRONINUM IN THE MATTER

7. POSITRONIUM in the condensed matter thermallization Processes leading to o-Ps lifetime shortening: - ortho-para conversion - quenching - pick-off

8. POSITRONIUM in the condensed matter pick- off process Shortening of the o-Ps lifetime value: 1 to 142 ns

9. 1  λ po =λ b P Dependence of the mean o-Ps lifetime value on the free volume size and shape POSITRONIUM in the condensed matter

10. Porous materials

11. EXCITED STATES Spherical potential well Porous materials

12. Decay constant for nl-th state, spherical shape: Decay constanst of pick-off process (averaged over all populated states) : ETE model Decay constant of nm-th state, cyllindrical shape: Porous materials

13. PALS vs LN Porous materials

14. 2.6y 3.7ps  + 90.4%, EC 9.5%  + 0.006% 1.274 0  PALS Positron Annihilation Lifetime Spectroscopy 1274 keV511 keV tt 1274 keV counts Channel number (energy )

15. PAL spectrometer

17. Lifetime spectrum

18. Spectrum analysis – convolution („LT”) J. Kansy, Nucl. Instr. Methods A 374, 235 (1996). Time, ns counts

19. examples

20. Fitted components: 2. Intensity of i-th component (I) 1.Mean lifetime value (  ) Defected metal time counts Nondefected metal

21. CYTOP Glass transition T=108 0 C M. Śniegocka, PhD Thesis, Lublin 2010 POLYMERS

22. Phase transition in alkanes C 13 H 28 C 15 H 32 C 17 H 36 C 19 H 40 B. Zgardzińska, PhD Thesis, Lublin 2008

23. Low-k materials pollution sorption photonics Porous materials

24. R = 0.99 nm R = 1.55 nm R = 2.38 nm http://chem.ch.huji.ac.il/~renata/ PHOTON ACTIVE GLASSES Porous materials

25. MCM-41 Porous materials [1] R. Zaleski, PhD thesis, Lublin (2005)

26. 1 - PG, 2 – PG + dye 3 – PG + AgNPs Porous materials

27. Thank you for your attention