The annealing of crystalline defects in Si single crystals created by ion implantation at room temperature was investigated. Silicon single crystals were firstly implanted at room temperature with ...1.345 MeV Au1+ ions at fluences from 1 × 1013 to 1 × 1014 at/cm2 to induce damage. A second implantation at room temperature was afterwards performed with 10 MeV Co3+ ions at a fluence of 3 × 1014 at/cm2. All samples were analyzed afterwards by Rutherford backscattering in random and channeling geometry to assess the crystalline damage present in the surface region. The results showed a significant reduction of the degree of damage or a reduction of the size of damaged region. The morphology and local atomic structure, studied using high-resolution electron microscopy, selected area electron diffraction and high resolution X-ray diffraction confirmed the reduction of damage degree and volume caused by Au implantation after Co implantation.
ERDA at the 9MV Tandem and at the 3MV Tandetron of IFIN-HH Petrascu, H.; Petrascu, M.; Pantelica, D. ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
09/2017, Letnik:
406
Journal Article
Recenzirano
Recoil spectrometry using heavy ions proposed in 1976 by L’Ecuyer has evolved into a universal IBA technique. Few years later an experimental setup for simultaneous light and medium heavy element ...detection including a compact ΔE(gas)–Er(solid) telescope, was developed at the Tandem accelerator of IFIN-HH. To increase the resolution, an integrated preamplifier was mounted close to the ionization chamber. The calibration procedure for the telescope and the software for the quantitative evaluation of the data are briefly presented. Recently, a 3MV Tandetron accelerator has been installed and commissioned at the IFIN-HH. Among several ion-beam techniques for detection and depth profiling of hydrogen isotopes, Elastic Recoil Detection Analysis (ERDA) technique using a low energy 4He beam, proposed by Doyle and Peercy, is particularly advantageous. By measuring simultaneously both the H or D recoiling at a forward angle and backscattered 4He ions, a rather complete characterization of the sample can be achieved. Selected results from our investigations, obtained using these facilities, are presented.
An experimental set-up designed to investigate the origin of the prompt scission neutrons in fission processes by using an array neutron detector is modeled. Quantities of interest as the correlation ...function strength in the momentum space within a model of independent one-particle pointlike sources, with a Gaussian distribution for the neutron generation points are obtained in a preliminary investigation. Two working hypothesis are used: i) the scission neutrons are emitted from the neck between fragments, in the final stage of the fission process, and ii) the post-scission neutrons are emitted from the accelerated fission fragments. For the scission neutrons emitted from the neck, a n-n correlation strength significantly larger than that obtained for neutrons emitted from the fission fragments is obtained. The results indicate that it is possible to discriminate scission and post-scission neutrons within an time-of-flight experimental set-up consisting from an array neutron detector combined with a VME acquisition system, using (p,xnf) reactions on actinide targets at the Bucharest Tandem.
ERDA at the 9 MV Tandem and at the 3 MV Tandetron of IFIN-HH Petrascu, H.; Petrascu, M.; Pantelica, D. ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
09/2017, Letnik:
406
Journal Article
Abstract
The NUMEN project aims to measure specific reaction cross sections to provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless ...double beta decay (0
νββ
). In particular, it was proposed to use heavy – ion induced double charge exchange reactions as tools towards the determination of information on the nuclear matrix elements of 0
νββ
, strongly motivated by a number of similarities between the two processes. To this extent, the
20
Ne +
130
Te system was experimentally investigated in a multi-channel approach by measuring the complete net of reactions channels, namely double charge exchange, single charge exchange, elastic and inelastic scattering, one – and two – nucleon transfer reactions, characterized by the same initial projectile and target nuclei. The goal of the study is to fully characterize the properties of the nuclear wavefunctions entering in the 0
νββ
decay nuclear matrix elements. The experimental setup, the data reduction and some of the obtained results for the
20
Ne +
130
Te system will be presented and discussed.
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