Search results for "Radio"
showing 10 items of 8895 documents
High-Gradient RF laboratory at IFIC for medical applications
2018
General interest has been shown over the last years for compact and more affordable facilities for hadron-therapy. The High-Gradient (HG) know-how and technology for normal-conducting accelerating RF (Radio-Frequency) electron linac (linear accelerator) structures recently developed for projects such as CLIC (CERN), has raised the achievable accelerating gradient from 20-30 MV/m up to 100-120 MV/m. This gain has come through a better understanding of the high-power RF vacuum arcs or breakdowns (BD) phenomena, the development of quantitative HG RF design methods and refinements in fabrication techniques. This can allow for more compact linacs also for protons, which is potentially important …
Gamma-radioactive contamination in the area of Lesisko Reserve
2004
A GEM-TPC in twin configuration for the Super-FRS tracking of heavy ions at FAIR
2018
The GEM-TPC [1] described herein will be part of the standard beam-diagnostics equipment of the Super-FRS [2] . This chamber will provide tracking information for particle identification at rates up to 1 MHz on an event-by-event basis. The key requirements of operation for these chambers are: close to 100% tracking efficiency under conditions of high counting rate, spatial resolution below 1 mm and a superb large dynamic range covering projectiles from Z=1 up to Z=92. The current prototype consists of two GEM-TPCs inside a single vessel, which are operating independently and have electrical drift fields in opposite directions. The twin configuration is done by flipping one of the GEM-TPCs o…
Transport and extraction of radioactive ions stopped in superfluid helium
2003
A new approach to convert a high energy beam to a low energy one, which is essential for the next generation radioactive ion beam facilities, has been proposed and tested at Jyvaskyla, Finland. An open Ra-223 alpha-decay-recoil source has been used to produce radioactive ions in superfluid helium. The alpha spectra demonstrate that the recoiling Rn-219 ions have been extracted out of liquid helium. This first observation of the extraction of heavy positive ions across the superfluid helium surface was possible thanks to the high sensitivity of radioactivity detection. An efficiency of 36% was obtained for the ion extraction out of liquid helium. (C) 2003 Elsevier Science B.V. All rights res…
Use of fragmentation beams at LNS with CHIMERA detector
2012
The recent intensity upgrade of the LNS fragmentation beam is discussed. The available beams, the tagging procedures and details on the beam quality are reported. The experimental program started with the CHIMERA detector using such beams is also discussed with preliminary results and future perspectives. © Owned by the authors, 2012.
Sorption and mechanism studies of Cu2+, Sr2+ and Pb2+ ions on mesoporous aluminosilicates/zeolite composite sorbents
2020
The research aimed to develop a novel mesoporous aluminosilicate/zeolite composite by the template co-precipitation method. The effect of aluminosilicate (AlSi) and zeolite (NaY) on the basic properties and adsorption capacity of the resultant composite was conducted at different mass ratios of AlSi/NaY (i.e., 5/90, 10/80, 15/85, 20/80, and 50/50). The adsorption characteristics of such composite and its feedstock materials (i.e., aluminosilicates and zeolite) towards radioactive Sr2+ ions and toxic metals (Cu2+ and Pb2+ ions) in aqueous solutions was investigated. Results indicated that BET surface area (SBET), total pore volume (VTotal), and mesopore volume (VMeso) of prepared materials f…
Radioaktiivisten jätteiden kartoitus kiihdytinlaboratoriossa
2011
Kiihdytinlaboratoriossa syntyy radioaktiivista jätettä, joka on pääosin tutkimuksessa käytettävien laitteiden osia ja laitteiden huoltojätettä. Aktiivinen jäte tulee luokitella ja käsitellä Suomen lakien määrämällä tavalla. Tässä työssä kartoitettiin jätteestä mahdollisesti löytyviä radioaktiivisia nuklideja ja nuklidien havaitsemiseen sopivaa mittauslaitteistoa. Jäteosia mitattiin gammasäteilyä havaitsevalla mittauslaitteistolla. Osista tunnistettiin radioaktiiviset nuklidit ja laskettiin niiden aktiivisuudet. Näiden määritysten pohjalta päätetään jäteosien jatkokäsittely yhteistyössä viranomaisten kanssa.
Nuclear Data and Experiments for Astrophysics
2022
Nuclear astrophysics aims to understand the origin of elements and the role of nuclear processes in astrophysical events. Nuclear reactions and reaction rates depend strongly on nuclear properties and on the astrophysical environment. Nuclear inputs for stellar reaction rates involve a variety of nuclear properties, theoretical models, and experimental data. Experiments providing data for nuclear astrophysics range from stable ion beam direct measurements to radioactive beam experiments employing inverse kinematics or indirect methods. Many properties relevant for astrophysical calculations, such as nuclear masses and β-decays, have also been intensively studied. This contribution shortly i…
Development and application of laser technologies at radioactive ion beam facilities
2008
Radio emission of binary stars in the AB Doradus moving group
2016
We present a study of the radio emission and kinematics of a sample of stars belonging to the AB Doradus moving group through VLA and VLBI observations. The main aim of our study is to obtain precise estimates of the dynamical mass of young, low-mass stars, which in combination with photometric measurements provide precise benchmarks for calibrating pre-main-sequence (PMS) stellar evolutionary models. Calibration of PMS models appears essential as they are widely used to predict the masses of low mass objects as brown dwarfs and planets. Previous studies show that model predictions are in disagreement with experimental results for masses below 1.2 solar masses. Among the stars included in o…