1 AP / P 5 - 05 Applications of Positron Annihilation Spectroscopy
نویسندگان
چکیده
Positron annihilation spectroscopy techniques are well established nuclear techniques with applications which nowadays range from structural investigations of materials to investigations of biological samples and medical imaging. They have extensively been used more than thirty years, but with constant improvements in measuring methods and with new applications, especially in investigations of technologically important materials. In standard positron annihilation spectroscopy suitable positron source is used, and techniques include positron lifetime measurements, Doppler broadening spectroscopy and angular correlation measurements. In the recent times slow positron beams combined with these techniques are applied as well, providing depth-profiling of the samples. We are going to present digitized positron lifetime system and a novel system for simultaneous positron lifetime and Doppler broadening spectroscopy developed at the Department of Physics in Zagreb and measurements with these systems using Na as positron source. Their advantages compared to conventional systems and further development of the positron annihilation spectroscopy techniques by employing signal digitizers in multidetector systems and possible applications will be described.
منابع مشابه
Positron annihilation lifetime spectroscopy in nickel ferrite and iron oxide nanopowders
In this study, a positron annihilation lifetime spectrometer was set up and its resolution was optimized. The spectrometer is a fast-slow arrangement with time resolution of 250 ps. To obtain lifetime components and their intensities from analyzing positron annihilation lifetime spectrum, the Pascual software is used. Positrons are from a source of radioactive 22NaCl with 20 μCi activity enclos...
متن کاملپایداری سامانه اندازهگیری طول عمر پوزیترون و بررسی نوع و غلظت عیب ناشی از تابش الکترونهای 10 مگا الکترون ولتی بر نمونههای سیلیکونی نوع n و p
Positron annihilation lifetime spectroscopy method with valuation of non-destructive investigation of material, provides information about electron density, defect concentration, type of defects and atoms around the defects. The stability of the system was tested with a source. The time resolution of the whole system has been derived about 365 ps at FWHM. Then n- and p-type silicon samples we...
متن کاملPositron Annihilation Spectroscopy
Positron annihilation spectroscopy is nowadays well recognised as a powerful tool of microstructure investigations of condensed matter. An overview of the method aimed for users from other fields is given and supplemented with several examples of applications.
متن کاملPositron Annihilation Spectroscopy: A Review of Applications in Nanomaterials Thin films and Semiconductors
A brief review have been presented highlighting the use of positron annihilation spectroscopic techniques for exploring the physical properties of materials from bulk to nanocrystalline sized particles. Even though a direct correlation of the changed annihilation characteristics with predictable changes in the solid is certainly not possible, positron annihilation can be used for obtaining comp...
متن کاملStudies of unicellular micro-organisms Saccharomyces cerevisiae by means of Positron Annihilation Lifetime Spectroscopy
Positron and its bound state positronium are applied since a few decades as a tool in material investigations. Especially, positron annihilation lifetime spectroscopy (PALS) is widely used, as it gives a possibility to correlate the mean o-Ps lifetime value with cavity size in which annihilation undergoes. The relationship called Tao-Eldrup model [1, 2], describing o-Ps pick-off annihilation, a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2009