1. Frank Laboratory of Neutron Physics Summer school in Dubna 5.7.-25.7.2010 Prepared by: B. Andel (SVK), E. Govor (BLR), K. V. Mareš (CZE), M. Mazánová (SVK), A. Moravcsík (SVK), V. Voronova (BLR) Supervisor : prof. M. V. Frontasyeva, FLNP

2. The founders of FLNP

3. Introduction Neutron Activation Analysis (NAA) is a sensitive multi-element analytical technique used for both qualitative and quantitative analysis of major, minor, trace and rare elements NAA was discovered in 1936 by G. Hevesy (Hungary) and H. Levi (Denmark)

4. Forms of NAA Destructive ( radiochemical ) - the resulting radioactive sample is chemically decomposed, and the elements are chemically separated Nondestructive ( instrumental ) - the resulting radioactive sample is kept intact

5. Principle

6. Detection Irradiated samples are analyzed by gamma-spectrometry

7. Neutron sources Isotopic neutron sources ( 252 Cf, 242 Am) Neutron generators Nuclear reactors At FLNP the pulsed fast reactor IBR-2 is used

8. Neutrons Thermal 0.025 eV-0.5 eV Epithermal 0.5 eV-100 keV Fast 100 keV-25 MeV

9. Characteristics of INAA Non-destructive analysis The chemical form and physical state of the elements do not influence the activation and decay process Multi-element analytical technique C, H, N, O and Si do not activate well Suitable even for determination of masses in the order of 10 –6 –10 –9 g and less

10. Applications of INAA at FLNP Environmental studies (migration of pollutants in ecosystems, air pollution studies using moss-biomonitors) Biotechnology for medicine (development of new phar maceuticals and sorbents ) Material Science (high purity materials, nanoparticles and objects of national heritage)

11. Dependence of counts on distance between detector and gamma-source

12. References P. Bode: Instrumental and organizational aspects of a neutron activation analysis laboratoty http://www.sciner.com/Neutron/naa.html http://reactor.engr.wisc.edu/naa/ http://tin.er.usgs.gov/geochem/doc/inaa.htm http://reactor.engr.wisc.edu/naa/UWNRNAA.htm http://www.reak.bme.hu/Wigner_Course/WignerManuals/ Budapest/NEUTRON_ACTIVATION_ANALYSIS.htm http://archaeometry.missouri.edu/naa_overview.html

13. Foto by Kamil Vavrinec Mares Thank you for your attention