Search results for "Linear particle accelerator"
showing 10 items of 74 documents
Influence of gravity vector on eye movement elicited by linear acceleration.
1991
When the body/head motion is sensed by otolith organs, they respond not only to the resultant acceleration of the motion but also to the gravitational force. We investigated the influence of the gravity vector on the otolithic-ocular reflex caused by motion in normal subjects. The sled type linear accelerator, moving back and forth with a frequency of 0.25 Hz and an amplitude of 2 m, generated right-left linear acceleration with a maximum magnitude of 0.5 g. We tested every subject under seven different postures: 1) 135 degrees forward tilted (F.T.), 2) 90 degrees F.T., 3) 45 degrees F.T., 4) upright sitting, 5) 45 degrees backward tilted (B.T.), 6) 90 degrees B.T., and 7) 135 degrees B.T. …
Beam-based alignment of SRF cavities in an electron injector linac
2018
Proper alignment of accelerating cavities is an important issue concerning beam quality of linear rf-accelerators. In particular, SRF cavities of injector linacs using high accelerating gradients on low-velocity electron beams can deteriorate the beam quality significantly when not aligned sufficiently. On the other hand, knowing the exact position of every cavity after several cool-down cycles of a cryomodule can be difficult depending on the particular module design. We will report on operational experience on the SC injector of the Darmstadt superconducting recirculating linac and ERL (S-DALINAC) showing unwanted effects on beam dynamics and beam quality due to cavity misalignment, such…
Reconstruction of the Longitudinal Phase Portrait for the SC CW Heavy Ion HELIAC at GSI
2019
Proceedings of the 10th International Particle Accelerator Conference The 10th International Particle Accelerator Conference, Melbourne, Australia, 19 May 2019 - 24 May 2019; JACoW Publishing, Geneva, Switzerland 898-901 (2019). doi:10.18429/JACOW-IPAC2019-MOPTS024
Collimation of Target Induced Halo Following MAGIX at MESA
2019
The Mainz Energy-recovering Superconducting Accelerator (MESA) will be an electron accelerator allowing operation in energy-recovery linac (ERL) mode. It provides the opportunity to operate scattering experiments at energies of ~100 MeV with thin gas-targets. The MESA Internal Gas Target Experiment (MAGIX) aims to operate windowless jet targets and different gases up to Xenon to search for possible dark photon interactions, to precisely measure the magnetic proton radius and astrophysical S-factors. Investigations on the impact of the target on beam dynamics and beam losses are required for machine safety and to examine limits to ERL operation. The goal of this work is to understand target …
The REX-ISOLDE project
2002
REX-ISOLDE is a pilot experiment at ISOLDE/CERN to study the structure of neutron-rich nuclei (N=20, N=28) with post-accelerated radioactive ion beams (1). Therefore radioactive ions with charge state 1+, which are delivered by the online mass separator ISOLDE, are accelerated up to 2.2 MeV/u by means of a new concept. The radioactive ions are first accumulated in a Penning trap, then charge breeded to a charge-to-mass ratio of 1/4.5 in an Electron Beam Ion Source (EBIS) and finally accelerated. The LINAC consists of three components, namely a Radio Frequency Quadrupole (RFQ) accelerator, which accelerates the ions from 5 to 300 keV/u, an interdigital H-type structure (IH) with a final ener…
Status of REX-ISOLDE
2003
REX-ISOLDE [1] is a post-accelerator situated at the ISOLDE radioactive ion beam facility placed at CERN, Geneva. It’s main aim is to increase the energy of light (A < 50) radioactive ions from 60 keV to 0.8–2.2MeV/u. REX—ISOLDE uses a new concept of post-acceleration of radioactive ion beams by using charge breeding of the ions in a high charge state ion source and the efficient acceleration of the highly charged ions in a short LINAC using modern ion accelerator structures. In a first step the radioactive ions are captured in a large gas-filled Penning trap. The task is to accumulate, cool and bunch the beam and prepare it for the injection into an electron beam ion source (EBIS). Cooling…
Relativistic Effects and Two-Body Currents inH2(e→,e′p)nUsing Out-of-Plane Detection
2001
Measurements of the (2)H((-->)e,e(')p)n reaction were performed with the out-of-plane magnetic spectrometers (OOPS) at the MIT-Bates Linear Accelerator. The longitudinal-transverse, f(LT) and f(')(LT), and the transverse-transverse, f(TT), interference responses at a missing momentum of 210 MeV/c were simultaneously extracted in the dip region at Q2 = 0.15 (GeV/c)(2). In comparison to models of deuteron electrodisintegration, the data clearly reveal strong effects of relativity and final-state interactions and the importance of two-body meson-exchange currents and isobar configurations. We demonstrate that such effects can be disentangled by extracting these responses using the novel out-of…
Measurement of theτ−→K−π0ντbranching fraction
2007
A measurement of the tau(-)-> K-pi(0)nu(tau) branching fraction has been made using 230.2 fb(-1) of data recorded by the BABAR detector at the PEP-II e(+)e(-) collider, located at the Stanford Linear Accelerator Center (SLAC), at a center-of-mass energy root s close to 10.58 GeV. We measure B(tau(-)-> K-pi(0)nu(tau))=(0.416 +/- 0.003(stat)+/- 0.018(syst))%.
The 1.5GeV harmonic double-sided microtron at Mainz University
2008
Abstract At the Institut fur Kernphysik of Mainz University a harmonic double-sided microtron (HDSM) has been built to extend the experimental capabilities for nuclear and particle physics experiments to higher excitation energies. This novel microtron variant accelerates the 0.855 GeV continuous wave (cw) electron beam of the established three-staged race track microtron (RTM) cascade MAMI B up to 1.5 GeV. It consists of two normal conducting linear accelerators (linacs) through which the electrons are guided up to 43 times by a pair of 90°-bending magnets at each end. For beam dynamical reasons the linacs operate at the harmonic frequencies of 4.90 and 2.45 GHz. The extended facility is c…
Results of the 1999 H8 beam tests of ATLAS-SCT prototypes
2001
Abstract During the August–September 1999 test beam in H8 at CERN three half-modules, equipped with different types of fast binary Front End electronics, have been tested. The results indicate that all three SCT electronics candidates satisfy ATLAS efficiency and noise occupancy requirements. In addition, a study on the effect of detector bias voltage on efficiency (ballistic deficit) is reported.