Search results for "cathode"

POLARIZED ELECTRONS AND POSITRONS AT THE MESA ACCELERATOR

2011

We suggest starting an accelerator physics project called the Mainz Energyrecovering Superconducting Accelerator (MESA) as an extension to the experimental facilities at the institute for nuclear physics. MESA may allow us to introduce an innovative internal target regime based on the ERL principle. A second mode of operation will be to use an external polarized electron beam for parity violating experiments. Furthermore, MESA could also allow us to establish a CW source of polarized positrons.

INVESTIGATION OF FAR-INFRARED SMITH-PURCELL RADIATION AT THE 3.41 MEV ELECTRON INJECTOR LINAC OF THE MAINZ MICROTRON MAMI

2006

The photon tagging facility at the Saskatchewan Accelerator Laboratory

1993

Abstract A photon tagging facility has been constructed for use with the c.w. electron beam at the Saskatchewan Accelerator Laboratory (SAL). The facility consists of a “clam-shell” type magnetic spectrometer with a 62 channel plastic scintillator focal plane detector allowing a post-bremsstrahlung electron energy resolution of 1%. Specialized focal plane and coincidence electronics have been designed and constructed at SAL and allows experiments to be performed with average tagged photon rates of greater than 1 × 108/s.

Recent results from experiments at MAMI

2012

Abstract The Mainz Microtron MAMI is an ideal tool for studying the structure of strongly interacting systems with an electromagnetic probe. With the new HDSM accelerator stage of MAMI C, a continuous-wave electron beam with an energy of up to 1604 MeV and excellent beam quality is available for precision experiments. In addition, polarisation degrees of freedom can be exploited with polarised beams and either polarised targets or recoil polarimetry. This paper presents selected results of the A1, A2, and A4 collaborations.

Hypernuclear Spectroscopy with Electron Beams

2011

A Λ-hyperon bound to a nuclear core, forming a hypernuclei, is a unique probe of the interior of hadronic many-body systems. Only recently, the spectroscopy of Λ-hypernuclei with electron beams was realized. Today, two places worldwide offer the possibility to study hypernuclei with high intensity continuous electron beams: MAMI at Mainz, Germany, and Jefferson Lab (JLab), Virginia. At least two different techniques exist for such studies: reaction spectroscopy, which requires two high-resolution spectrometers, one for kaons and one for the scattered electrons, and decay particle spectroscopy of hyperfragments. In the latter case a strangeness tagger in forward direction is of great advanta…

Effect of the tilt on the gyrotron operation

2013

The effect of the tilt of the electron beam axis on the gyrotron operation is investigated. It is commonly accepted that the tilt deteriorates the efficiency of cylindrical cavity gyrotrons. Our study showed that this deterioration can be mitigated by a proper displacement of the electron beam axis at the entrance. Also, in some cases, when the aftercavity interaction lowers the gyrotron efficiency, the tilt can reduce this interaction and, therefore, slightly increase the efficiency.

Experimental validation of a novel compact focusing scheme for future energy-frontier linear lepton colliders.

2014

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [ P. Raimondi and A. Seryi , Phys. Rev. Lett. 86 , 3779 ( 2001 ) ]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

Elektronen-Einschleusung In Ein Mikrotron Mittels Eines Resonanzemitters Im Resonator

1963

Abstract A cathode arrangement is described by means of which a highly efficient injection of electrons into a microtron is achieved. It is a part of a resonant circuit coupled to the resonator and oscilating with a suitable phase. The electric field configuration in the reentrance hole of the resonator has a focusing effect on the electrons.

Deep sea tests of a prototype of the KM3NeT digital optical module: KM3NeT Collaboration

2014

The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deep waters of the Mediterranean Sea. This digital optical module has a novel design with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same $^{40…

How narrow is the linewidth of parametric X-ray radiation?

1997

Parametric x-ray or quasi-Cherenkov radiation is produced by the passage of an electron through a crystal. A critical absorber technique has been employed to investigate its linewidth. Experiments have been performed with the 855MeV electron beam from the Mainz Microtron MAMI. Thin absorber foils were mounted in front of a CCD camera serving as a position sensitive photon detector. Upper limits of the linewidth of 1.2 and 3.5eV were determined for the (111) and (022) reflections of silicon at photon energies of 4966 and 8332eV. These limits originate from geometrical line broadening effects that can be optimized to reach the ultimate limit given by the finite length of the wave train. {copy…