Search results for "Linear particle accelerator"
showing 10 items of 74 documents
Achievements and Perspectives in the Search for Super Heavy Elements
2004
The elements with the atomic numbers 107-112 have been synthesized and unambiguously identified at the velocity filter SHIP at GSI. The technique allowing for this successful experimental program is the combination of the detection of correlations between evaporation residues and subsequent a-decays with a powerful separator. The sensitivity limit of the set-up at GSI has reached the lpb level. For systematic investigation in this region of extremely low cross section and to synthesize nuclei of higher Z this limit has to be pushed to even lower values. An extensive development program is pursued at SHIP in order to reach at least an order of magnitude lower cross sections. Apart from targe…
Emittance Growth by Synchrotron Radiation in a Double-Sided Microtron
1999
Here we present results of calculations of emittance growth caused by quantum fluctuations of synchrotron radiation (QFSR) for a 1.5 GeV double-sided microtron (DSM). We did both semi-analytical estimations, employing known Twiss parameters for the DSM orbits, and a computer simulation of these stochastic effects using the program SYTRACE. This showed that the normalized emittance growth was within reasonable limits, by a factor of about 1.5, thus permitting e.g. the installation of small aperture linacs on the DSM axes.
Status and prospects of Rn measurements at Mainz
2013
Parity-violating electron scattering is particularly sensitive to the neutron density. The recent PREX experiment at the Jefferson Laboratory (JLab) has demonstrated the feasibility of this method meanwhile outlining its major experimental challenges. On the other side intermediate energy photons are an ideal probe for studying the properties of strongly interacting matter from the nuclear scale down to the sub-nuclear components of the nucleus. Among others, coherent pion photoproduction on nuclei is an attractive approach to obtain information on the existence and nature of neutron skins in nuclei. The simultaneous combination of different techniques allows a systematic determination of t…
Sensitivity of alanine dosimeters with gadolinium exposed to 6 MV photons at clinical doses.
2011
In this study we analyzed the ESR signal of alanine dosimeters with gadolinium exposed to 6 MV linear accelerator photons. We observed that the addition of gadolinium brings about an improvement in the sensitivity to photons because of its high atomic number. The experimental data indicated that the addition of gadolinium increases the sensitivity of the alanine to 6 MV photons. This enhancement was better observed at high gadolinium concentrations for which the tissue equivalence is heavily reduced. However, information about the irradiation setup and of the radiation beam features allows one to correct for this difference. Monte Carlo simulations were carried out to obtain information on …
Investigation of correction factors for non-reference conditions in ion chamber photon dosimetry with Monte-Carlo simulations.
2009
Current dosimetry protocols require geometrical reference conditions for the determination of absorbed dose in external radiotherapy. Whenever these geometrical conditions cannot be maintained the application of additional corrections becomes necessary, in principle. The current DIN6800-2 protocol includes a corresponding factor k(NR), but numerical values are lacking and no definite information about the magnitude of this correction is available yet. This study presents Monte-Carlo based calculations within the 6 MV-X photon field of a linear accelerator for a common used ion chamber (PTW31010) employing the EGSnrc code system. The linear accelerator model was matched to measurements, show…
Photonuclear reactions with zinc: A case for clinical linacs
2015
WOS: 000365732300003
A superconducting CW-LINAC for heavy ion acceleration at GSI
2017
The European physical journal / Web of Conferences 138, 01026 (2017). doi:10.1051/epjconf/201713801026
Collimation for CLIC
2003
The collimation system of the Compact Linear Collider (CLIC) must fulfil a number of conflicting requirements, namely it should (1) remove beam halo to reduce the detector background, (2) provide a minimum distance between collimators and collision point for muon suppression, (3) ensure collimator survival and machine protection against errand beam pulses, (4) not be excessively long, and (5) not amplify incoming trajectory fluctuations via the collimator wake fields. Two optical systems have been designed — the first linear, the second non‐linear —, which promise to meet all these requirements for the design beam energy of 1.5 TeV. We decribe the various design criteria, a preliminary perf…
A three domain controller for a high frequency high power four quadrant power converter for superconducting magnets
2002
The paper describes the implementation of a controller that orchestrates the functioning of three subsystems that implement a high energy converter (/spl plusmn/1500 A, /spl plusmn/15 V) that supplies a superconducting magnet to be used in particle accelerators. The performance of the whole system, in accordance to specifications, is documented with experimental results.
Extension of Electron Monte Carlo Dose Calculation in Eclipse to Siemens Linear Accelerators
2009
Initially, the implementation of the macro Monte Carlo (MC) method into Eclipse (Varian Medical Systems), named eMC, was carried out for Varian accelerators only. In this work eMC algorithm has been modified to allow also accurate dose calculations for electron beams for Siemens accelerators.