Search results for "accelerator"
showing 10 items of 1507 documents
Proposal for SPS beam time for the baby MIND and TASD neutrino detector prototypes
2014
The design construction and testing of neutrino detector prototypes at CERN are ongoing activities. This document reports on the design of solid state baby MIND and TASD detector prototypes and outlines requirements for a test beam at CERN to test these tentatively planned on the H8 beamline in the North Area which is equipped with a large aperture magnet. The current proposal is submitted to be considered in light of the recently approved projects related to neutrino activities with the SPS in the North Area in the medium term 2015 2020.
Fast timing and trigger Cherenkov detector for collider experiments
2016
Analysis of fast timing and trigger Cherenkov detector’s design for its use in collider experiments is presented. Several specific requirements are taken into account – necessity of the radiator’s placement as close to the beam pipe as possible along with the requirement of gapless (solid) radiator’s design. Characteristics of the Cherenkov detector’s laboratory prototype obtained using a pion beam at the CERN Proton Synchrotron are also presented, showing the possibility of obtaining sufficiently high geometrical efficiency along with good enough time resolution (50 ps sigma). peerReviewed
Data quality monitors of vertex detectors at the start of the Belle II experiment
2019
The Belle II experiment features a substantial upgrade of the Belle detector and will operate at the SuperKEKB energy-asymmetric e+e− collider at KEK in Tsukuba, Japan. The accelerator completed its first phase of commissioning in 2016, and the Belle II detector saw its first electron-positron collisions in April 2018. Belle II features a newly designed silicon vertex detector based on double-sided strip layers and DEPFET pixel layers. A subset of the vertex detector was operated in 2018 to determine background conditions (Phase 2 operation). The collaboration completed full detector installation in January 2019, and the experiment started full data taking. This paper will report on the fin…
Future Linear Colliders: Detector R&D, Jet Reconstruction and Top Physics Potential
2016
RESUMEN: Durante el siglo XX, los descubrimientos de nuevas partículas y las medidas realizadas en los colisionadores, junto con el progreso de la física teórica, nos permitieron formular el Modelo Estándar (SM) de las interacciones entre los constituyentes de la materia. El descubrimiento del bosón de Higgs en el LHC fue un gran paso en nuestra compren- sión de las interacciones fundamentales de la naturaleza y la estructura de la materia descrita por el Modelo Estándar. Con el fin de establecer el mecanismo de ruptura de simetría electrodébil, todas las propiedades del bosón de Higgs (masa, acoplamientos, amplitud de desintegración, espín) deben medirse con precisión. El LHC tiene excelen…
Electrooptic beam deflection with latex
1988
The use of latex in electrooptic devices is proposed. The static non linearity coefficient is shown to be approximatively 200 times the optical one. The theory of a beam deflector is developed and an explicit expression is given for the deflection angle versus the physical parameters of the sample Utilisation de suspensions aqueuses de latex dans un dispositif electro-optique. On montre que le coefficient statique de non-linearite devrait etre 200 fois plus eleve que le coefficient optique. Application a un deflecteur optique
Efficiency investigation of a negative hydrogen ion beam production with the use of the gasdynamic ECR plasma source
2020
Negative hydrogen ion sources are of great demand in modern physics as injectors into accelerators and drivers for neutral beam injectors for fusion devices. It has been shown earlier that the use of the gasdynamic ECR discharge provides the opportunity to extract up to 80 mA/cm2 of negative ion current density. We studied experimentally the volumetric negative hydrogen ion production and vacuum ultraviolet emission in a gasdynamic ECR discharge. The high-density plasma was sustained by the pulsed 37 GHz / 100 kW gyrotron radiation in a magnetic configuration consisting of two consecutive simple mirror traps. The future prospects of the volumetric H– source based on the gasdynamic ECR disch…
Development of a MeV ion beam lithography system in Jyväskylä
2007
A lithographic facility for writing patterns with ion beams from cyclotron beams is under development for the Jyväskylä cyclotron. Instead of focusing and deflecting the beam with electrostatic and magnetic fields a different approach is used. Here a small rectangular beam spot is defined by the shadow of a computer-controlled variable aperture in close proximity to the sample. This allows parallel exposure of rectangular pattern elements of 5–500 μm side with protons up to 6 MeV and heavy ions (20Ne, 85Kr) up to few 100 MeV. Here we present a short overview of the system under construction and development of the aperture design, which is a critical aspect for all ion beam lithography syste…
Diagnostic techniques of minimum-B ECR ion source plasma instabilities.
2022
The performance of a minimum-B Electron Cyclotron Resonance Ion Source (ECRIS) is traditionally quantified by measuring the beam current and quality of the extracted ion beams of different charge state ions. The stability of the extracted ion beam currents has drawn more attention recently as the technology is pushing its limits toward higher ion charge states and beam intensities. The stability of the extracted beam is often compromised by plasma instabilities manifesting themselves as rapid oscillations of the beam currents in millisecond scale. This paper focuses on practical aspects of diagnostics techniques of the instabilities, showcases examples of instability-related diagnostics sig…
Angular spreading measurements using MeV ion microscopes
2013
Abstract The sharpness of MeV ion microscope images is governed by small-angle scattering and associated lateral spreading of the ion beam in the sample. We have investigated measurement of the half-angle of the angular spreading distribution by characterising the image blurring in direct-Scanning Transmission Ion Microscopy (direct-STIM). In these tests Mylar™ foils of 0.5–6 μm were used to induce angular spreading. Images were taken of an electron microscope grid using 2 MeV protons with, and without, the foils in the beam path. The blurring was measured by fitting the width of a circular Gaussian point spread function to the images with and without the foil in position. The results show …
Effect of magnetic field on the corrosion of iron and St20 steel as studied by positron annihilation
2010
Lifetime spectra of positron annihilation in iron and St20 steel corroded in the water solution of HCl and in vapour above its surface have been investigated with emphasis on the effect of corrosion time and environment (solution or vapour) as well as of the presence and orientation of the magnetic field on the measured positron annihilation parameters. All the registered positron lifetime spectra consist of two components. For corroded samples the intensities of the two components as well as the corresponding values of the mean positron lifetime, differ from those for uncorroded material. The corrosion-induced changes in the positron annihilation parameters depend on the corrosion environm…