Search results for "Physics::Accelerator Physics"
showing 10 items of 1235 documents
First Capture of Antiprotons in a Penning Trap: A Kiloelectronvolt Source
1986
Antiprotons from the Low Energy Antiproton Ring of CERN are slowed from 21 MeV to below 3 keV by being passed through 3 mm of material, mostly Be. While still in flight, the kiloelectronvolt antiprotons are captured in a Penning trap created by the sudden application of a 3-kV potential. Antiprotons are held for 100 s and more. Prospects are now excellent for much longer trapping times under better vacuum conditions. This demonstrates the feasibility of a greatly improved measurement of the inertial mass of the antiproton and opens the way to other intriguing experiments.
High current proton beams production at Simple Mirror Ion Source 37
2014
This paper presents the latest results of high current proton beam production at Simple Mirror Ion Source (SMIS) 37 facility at the Institute of Applied Physics (IAP RAS). In this experimental setup, the plasma is created and the electrons are heated by 37.5 GHz gyrotron radiation with power up to 100 kW in a simple mirror trap fulfilling the ECR condition. Latest experiments at SMIS 37 were performed using a single-aperture two-electrode extraction system. Proton beams with currents up to 450 mA at high voltages below 45 kV were obtained. The maximum beam current density was measured to be 600 mA/cm2. A possibility of further improvement through the development of an advanced extraction sy…
The Cryogenic Pumping Section of the KATRIN Experiment
2010
In order to determine the absolute scale of the neutrino mass with a sensitivity of 0.2 (90% Confidence Level), the Karlsruhe Tritium Neutrino experiment (KATRIN) operates a series of superconducting magnet systems, which guide the electrons adiabatically from the source of tritium beta-decay to the detector within a magnetic flux of 191 . The 7 m long Cryogenic Pumping Section (CPS) is designed as the final barrier of tritium circulation. It has to reduce the tritium partial pressure below Pa in order to limit the background count rate in the measurement. To achieve this, the tritium entering the CPS must be adsorbed onto a pre-condensed argon layer on the inner surface of the beam tube at…
Collinear two-photon excitation of indium rydberg states in a fast atomic beam
1986
The 29p-Rydberg state of neutral indium was produced by double resonant two-photon excitation in a fast atomic beam and detected via field ionization in a longitudinal electric field.
Angular shift of an electromagnetic beam reflected by a planar dielectric interface
1989
A mathematical procedure for obtaining theoretically an expression for the fields of a beam reflected by a planar interface separating two lossless, linear, isotropic, homogeneous media is presented. Comparison of this expression with that obtained when the beam undergoes reflection from a perfect conductor leads to the expression for the angular shift of the beam reflected by a planar dielectric interface. The cases of normal and parallel polarization of a microwave beam are considered. In the last case, a complete study for angles of incidence far and near the Brewster angle is made.
Neutron momentum distributions from "core break-up" reactions of halo nuclei
1995
Neutron angular distributions from violent break-up reactions of Li-11 and Be-11 have been measured at 28 MeV/u and 280 MeV/u and at 41 MeV/u and 460 MeV/u, respectively. The derived neutron momentum distributions show a narrow component in transverse momentum that is within uncertainties independent of beam energy and target charge. This component is suggested to be simply related to the momentum distribution of the loosely bound halo neutron(s) in the projectiles.
Proton polarizabilities: status, relevance, prospects
2013
This is a brief review of the status of understanding the proton polarizabilities in chiral perturbation theory and of their relevance to the `proton charge radius puzzle'.
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…
Beam blowup in race track microtrons
1979
Abstract Beam blowup of the special kind to be expected with race track microtrons is investigated using a simplified model. A worst case analytical estimation formula is briefly derived. Further, the results of a large number of numerical computations are communicated and it is tried to compress these results to a simple empirical estimation formula. Finally, microwave measurements of BBU shunt impedances and some methods to overcome BBU are briefly discussed.
The exact solution of the diffusion trapping model of defect profiling with variable energy positrons
2013
We report an exact analytical solution of so-called positron diffusion trapping model. This model have been widely used for the treatment of the experimental data for defect profiling of the adjoin surface layer using the variable energy positron (VEP) beam technique. Hovewer, up to now this model could be treated only numerically with so-called VEPFIT program. The explicit form of the solutions is obtained for the realistic cases when defect profile is described by a discreet step-like function and continuous exponential-like function. Our solutions allow to derive the analytical expressions for typical positron annihilation characteristics including the positron lifetime spectrum. Latter …