Introduction to Slow Positron

Doppler Broadening Spectroscopy and Coincidence Doppler Broadening Spectroscopy both based on slow positron beam were employed in the current work to characterize the depth distribution and the chemical surroundings of the irradiation-induced defects.

For the GBAR (Gravitational Behaviour of Antihydrogen at Rest) experiment at CERN’s Antiproton Decelerator (AD) facility we have constructed a source of slow positrons, which uses a low-energy electron linear accelerator (linac).

Doppler broadening spectroscopy (DBS) and coincidence Doppler broaden spectroscopy (CDB) based on slow positron beam and synchrotron X-ray diffraction technology were employed in the current work.

Slow positron beam experiments have been performed on two set of samples.

The crystal structure, morphology, microscopic defects and optical properties of the ZnSe films were characterized by XRD, SEM, Raman spectroscopy, UV–visible spectrophotometer and slow positron beam Doppler broadening spectroscopy, respectively.

Monte Carlo radiation transport simulations were used to calculate the slow positron yields from tungsten foil positron moderators at a reactor-based slow positron source.

Applying a slow positron beam, the formation of defect clusters induced by ion irradiation and the thermal stability of defects formed at 300 K were investigated.

The microdefects in the subsurface region and the surface damage caused by irradiation were characterized by Doppler broadening spectroscopy (DBS) of slow positron beam, transmission electron microscope (TEM) and scanning electron microscopy (SEM), respectively.

Although numerous studies reporting the use of slow positron beam (SPB) experiments on ion-implanted materials have been published in the literature, only a few of them address the continuous distribution of microstructural damage introduced by ion beam.

Slow Positron Beam (PB) is an important device in the study of positron physics andtechniques, especially in material research.

Given such a source of fast positrons for use in the optimized magnetic bottle device, a slow positron beam intensity of 2 ÷ 10 × 104 s−1 can be achieved.

The application of slow positrons to diagnosing materials is examined and the techniques of positron microscopy and microprobing are presented.

Ion irradiation combined with a slow positron beam could be used to evaluate irradiation damage correlated with embrittlement of nuclear materials.

Slow positron beam was applied to study the depth profile structure of the virgin and the aged high-temperature vulcanized silicone rubber (HTV).

We constructed a new apparatus, built upon a trap-based slow positron beam, for the production of a collimated, energy-tunable positronium beam under ultra-high vacuum conditions employing the photodetachment of positronium negative ions.

The analysis of the data has been done with different techniques, the distribution of the Cr and/or vacancies around probe nuclei has been explored by Mossbauer spectroscopy and the vacancy profile by Slow Positron Annihilation Spectroscopy (SPAS).

In this work, a non- invasive technique, a slow positron beam, coupled with Doppler broadening energy spectroscopy (DBES), is applied to study the void defects within the interfacial layer between CA films and Si and SiO2 substrates.

Ion-irradiated U(Al,Si)3 intermetallide, as an example of compounds with significantly different atomic masses of constituting atoms, was studied by slow positron beam spectroscopy in order to clarify the nature of defects accompanying the process of the ion-induced disordering of this material.

The crystal structure, surface morphology, microscopic defects and optical properties of the samples were measured by XRD, SEM, slow positron beam Doppler broadening spectroscopy and UV–visible spectrophotometer, respectively.

01 wt%) reactor pressure vessel (RPV) steel were conducted by slow positron beam (SPB), TEM, and nanoindentation.

The results of slow positron annihilation spectroscopy (PAS) experiments suggest that abundant vacancy-type defects were introduced in the helium-irradiated nickel foil.

Open volume defect profiles have been obtained in He, O and (He + O) ion implanted silicon crystal 〈1 0 0〉 using slow positron beam measurements.

In addition, the thin films were depth profiled using a slow positron beam to investigate the role of vacancies.

2 dpa by 110-keV proton at room temperature were investigated by slow positron beam, TEM, and nanoindentation.

Results of slow positron beam show that the S parameter decreased obviously after single (H or He) ions beam irradiation compared to the pre-damaged specimen, which indicate H or He (Hn or Hen) clusters deposit at the damage area caused by Ni ion irradiation and they occupy vacancy sites (Vm), resulting in the formation of numerous HnVm or HenVm clusters.

A slow positron facility is being built in Israel, at the Hebrew University, for basic and applied research.