Search results for "Physics::Accelerator Physics"
showing 10 items of 1235 documents
Helicity Dependence ofγp→Nπbelow 450 MeV and Contribution to the Gerasimov-Drell-Hearn Sum Rule
2000
The helicity dependence of the single pion photoproduction on the proton has been measured in the energy range from 200 to 450 MeV for the first time. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a frozen-spin target. The data obtained provide new information for multipole analyses of pion photoproduction and determine the main contributions to the Gerasimov-Drell-Hearn sum rule and the forward spin polarizability gamma(0).
Search for Dark Photons with Accelerators
2014
A dark photon as the mediator of an interaction of the dark sector is a well motivated extension of the standard model. While possible dark matter particles are heavy and seem to be beyond the reach of current accelerators, the dark photon is not necessarily heavy and might have a mass in the range of existing accelerators. In recent years, an extensive experimental program at several accelerators for the search for dark photons were established. In this talk, recent results and progress in the determination of exclusion limits with accelerators is presented.
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.
The PANDA Barrel DIRC
2016
The PANDA detector at the international accelerator Facility for Antiproton and Ion Research in Europe (FAIR) addresses fundamental questions of hadron physics. Experiments concerning charmonium spectroscopy, the search for hybrids and glueballs and the interaction of hidden and open charm particles with nucleons and nuclei will be performed with antiproton beams impinging on hydrogen or nuclear targets. Cooled beams allow the precision scan of resonances in formation experiments. The momentum range of the antiproton beam between 1.5 GeV/c and 15 GeV/c tests predictions by perturbation theory and will reveal deviations originating from strong QCD . An excellent hadronic particle identificat…
Electromagnetic Calorimeter for HADES Experiment
2014
Electromagnetic calorimeter (ECAL) is being developed to complement dilep- ton spectrometer HADES. ECAL will enable the HADES@FAIR experiment to mea- sure data on neutral meson production in heavy ion collisions at the energy range of 2-10 AGeV on the beam of future accelerator SIS100@FAIR. We will report results of the last beam test with quasi-monoenergetic photons carried out in MAMI facility at Jo- hannes Gutenberg Universitat Mainz.
The design of a cascaded 800 MeV normal conducting C.W. race track microtron
1976
Abstract A c.w. electron accelerator of 820 MeV maximum output energy at 100 μ A beam current is proposed to make possible a large variety of coincidence experiments with energy electrons and photons as a future possibility of new, interesting experiments. It consists of a preaccelerator and 3 cascaded race track microtons using normal conducting rf structures. The design of this accelerator, based on detailed computational investigations of its beam dynamics and some experimental studies, is communicated and partly discussed in this paper.
A new measurement of the neutron detection efficiency for the NaI Crystal Ball detector
2015
We report on a measurement of the neutron detection efficiency in NaI crystals in the Crystal Ball detector obtained from a study of single π0 photoproduction on deuterium using the tagged photon beam at the Mainz Microtron. The results were obtained up to a neutron energy of 400 MeV . They are compared to previous measurements made more than 15 years ago at the pion beam at the BNL AGS.
Target and beam-target asymmetry measurements at MAMI
2014
Preliminary data for target and beam-target asymmetry for the reaction $\gamma p\to\pi^0\eta p$ obtained at the MAMI accelerator are presented. The data are compared to different theoretical predictions.
First Measurements with the DTAS Detector
2016
The DTAS detector will be an important instrument in the DESPEC experiment at FAIR for \(\beta \)-decay studies of exotic nuclei far from stability. The first measurements with this new detector have been performed with low energy radioactive beams at the upgraded IGISOL IV facility. The characterization of the detector was done by comparison of measurements with Monte Carlo (MC) simulations , and the first analysis of the cases of interest are in progress.
An experiment on the velocity distribution of thermionic electrons
2010
This paper describes an undergraduate experiment that yields the velocity distribution of thermionic electrons by analyzing the I-V characteristics of diodes and triodes. The experiment allows students to focus on the distribution function more than on difficulties arising from the complexity of thermionic emission. By using a simple model, the velocity distribution of thermionic electrons emitted by the vacuum tube cathode can be described by Maxwell’s distribution.