Beam phase measurement system for the K130 cyclotron in Jyväskylä (original) (raw)
Related papers
Review of Scientific Instruments, 2013
In an isochronous cyclotron, measurements of central phase of the ion beam with respect to rf and the phase width provide a way to tune the cyclotron for maximum energy gain per turn and efficient extraction. We report here the development of a phase measurement system and the measurements carried out at the Variable Energy Cyclotron Centre's (VECC's) K = 500 superconducting cyclotron. The technique comprises detecting prompt γ-rays resulting from the interaction of cyclotron ion beam with an aluminium target mounted on a radial probe in coincidence with cyclotron rf. An assembly comprising a fast scintillator and a liquid light-guide inserted inside the cyclotron was used to detect the γ-rays and to transfer the light signal outside the cyclotron where a matching photo-multiplier tube was used for light to electrical signal conversion. The typical beam intensity for this measurement was a few times 10 11 pps.
Central region upgrade for the Jyväskylä K130 cyclotron
2020
The Jyväskylä K130 cyclotron has been in operation for more than 25 years providing beams from H to Au with energies ranging from 1 to 80 MeV/u for nuclear physics research and applications. At the typical energies around 5 MeV/u used for the nuclear physics program the injection voltage used is about 10 kV. The low voltage limits the beam intensity especially from the 18 GHz ECRIS HIISI. To increase the beam intensities the central region of the K130 cyclotron is being upgraded by increasing the injection voltage by a factor of 2. The new central region with spiral inflectors for harmonics 1-3 has been designed. The new central region shows better transmission in simulations than the original one for all harmonics and especially for h=2 typically used for nuclear physics. The engineering design for the new central region is being done.
BEAM DIAGNOSTIC COMPONENTS FOR SUPERCONDUCTING CYCLOTRON AT KOLKATA
VEC Centre Kolkata has constructed a K500 superconducting cyclotron (SCC). Several beam diagnostic components have been designed, fabricated and installed in SCC. In the low energy beam line, uncooled slits, faraday cup, beam viewers, and collimators are used. The inflector is also operated in a faraday cup mode to measure the beam inside SCC. The radial probe and viewer probe are respectively used to measure beam current and to observe the beam size and shape inside SCC. The magnetic channels, electro-static deflectors and M9 slit are also used to measure beam current at the extraction radius. Water cooled faraday cup and beam viewers are used in the external beam line. The radius of curvature of the radial probe track was reduced to align the internal and external track during its assembly. It was observed that the probe did not functioning properly during beam trials. Different modifications were incorporated. But, problem with the probe persisted. The paper describes the beam diagnostic components used in the cyclotron, discusses the problems faced in operating the radial probe, modifications tried and outlines the future steps planned to operate the beam diagnostic components.
2013
This paper describes various measurements performed on the beam behaviour with the help of the main probes and the differential probe to have a clear insight of the accelerating beam and the difficulties of beam -extraction process in the K500 superconducting cyclotron at Kolkata. Beam shadow measurements with three probes at three sectors were done to get the information of beamcentering and radial oscillations. The radial oscillation amplitude is estimated from the measurements. A differential probe was used to measure the turn separation and its modulation due to radial oscillation. With the help of magnetic field detuning method, the beam phase history was also measured.
Beam Phase Detection for Proton Therapy Accelerators
2005
The industrial application of proton cyclotrons has become one of the important contributions of accelerator physics to medical therapy during the last years. Beam phase, energy, and intensity of the accelerated proton bunches can be detected by non-intercepting capacitive cylindrical probes. For the read out of the detected pulsed signals an advanced phase detection system using vector demodulating technique was developed. It has a very large dynamic range allow measurements over a beam current range of up to three orders of magnitude. In order to avoid interference from the fundamental cyclotron frequency of 72 MHz, the phase detection is performed at the second harmonic frequency. A phase detection range of 180° was achieved at the fundamental frequency. To improve accuracy a digital low pass filter with adjustable bandwidth and steepness is implemented. With an estimated sensitivity of the capacitive pickup in the beam line of 30 nV per nA proton beam at 250 MeV, accurate phase and intensity measurements are expected to be possible down to beam currents of 3.3 nA. First measurements at the cyclotrons will show how far the resolution will be limited to higher values by RF disturbance at the fundamental frequency.
Program to Improve the Ion Beam Formation and Transmission at Jyfl
2007
The increased requirements towards the use of higher ion beam intensities motivated us to initiate the project to improve the overall transmission efficiency of the K130 cyclotron facility at JYFL. A similar project has earlier been started at the NSCL/MSU (National Superconducting Cyclotron Laboratory/Michigan State University) where a remarkable improvement in the ion beam transmission has been obtained (1). Since
Development of an /sup 14/O ion beam at the 88" cyclotron
Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366), 1999
At the 88" Cyclotron at the Lawrence Berkeley National Laboratory we are developing an intense (3⋅10 7 pps), low energy 14 O ion beam to measure the shape of the betadecay spectrum. The 14
Cyclotrons: Magnetic Design and Beam Dynamics
arXiv: Medical Physics, 2017
Classical, isochronous, and synchro-cyclotrons are introduced. Transverse and longitudinal beam dynamics in these accelerators are covered. The problem of vertical focusing and iscochronism in compact isochronous cyclotrons is treated in some detail. Different methods for isochronization of the cyclotron magnetic field are discussed. The limits of the classical cyclotron are explained. Typical features of the synchro-cyclotron, such as the beam capture problem, stable phase motion, and the extraction problem are discussed. The main design goals for beam injection are explained and special problems related to a central region with an internal ion source are considered. The principle of a Penning ion gauge source is addressed. The issue of vertical focusing in the cyclotron centre is briefly discussed. Several examples of numerical simulations are given. Different methods of (axial) injection are briefly outlined. Different solutions for beam extraction are described. These include th...
Characteristics of Beam Extraction System of K500 Superconducting Cyclotron
Extensive Magnetic Field measurement of the K500 Superconducting Cyclotron has been completed. In this paper we report the beam dynamical calculations along the extraction system based on the measured magnetic field data. The beam matching to the external beam transport system, for different ion species spanning the operating region is also explored.
A Comparative Study Between Simulated and Measured Beam's Quality of 30 MeV Cyclotron at KFSHRC
2016
At King Faisal Specialist Hospital and Research Centre (KFSHRC), the C-30 Cyclotron (manufactured by IBA) is used to produce radioisotopes for medical purposes. Working with very expensive machine dedicated for patients needs full attention and understanding of how beam can be controlled safely inside beam transport system. Moreover, knowledge of influence of magnetic lenses on charged particles is desired. Therefore, using off-line source such as PC-based beam simulator allows an operator to immediately see the effect of various magnetic lenses attached to the beam line. Initially, the magnetic field of quadruples and steering magnet was recorded using Hall probe Teslameter. The magnetic field values then uploaded into the Beam simulator in which beam quality was recorded and analysed. INTRODUCTION Experience gained since the commissioning of the IBA [3] C-30 Cyclotron at the King Faisal Specialist Hospital and Research Centre (KFSHRC) in 2010, has shown this facility to be viable ...