Search results for "Instrumentation"
showing 10 items of 4914 documents
Enhanced radiation pressure-assisted acceleration by temporally tuned counter-propagating pulses
2014
Within the last decade, laser-ion acceleration has become a field of broad interest. The possibility to generate short proton- or heavy ion bunches with an energy of a few tens of MeV by table-top laser systems could open new opportunities for medical or technical applications. Nevertheless, today's laser-acceleration schemes lead mainly to a temperature-like energy distribution of the accelerated ions, a big disadvantage compared to mono-energetic beams from conventional accelerators. Recent results 111 of laser-ion acceleration using radiation-pressure appear promising to overcome this drawback. In this paper, we demonstrate the influence of a second counter-propagating laser pulse intera…
A highly polarized target for the electron beam at MAMI
2009
Abstract Polarized He 3 from metastability exchange optical pumping (MEOP) is used as an effective polarized neutron target for electron scattering experiments at the MAinz MIcrotron (MAMI). With the present setup an initial polarization of up to 72% has been obtained at the experimental area. A novel calibration technique will be presented which allows the determination of the absolute polarization within a relative uncertainty of 3%.
Probe prototypes based on TlBr detectors
2009
Abstract Detectors based on TlBr crystals are ideally suited for the probes, where small size and rapid stopping power are highly desirable attributes. The development results of TlBr probes for medical and nuclear industry applications are presented here. Probes for both applications include TlBr detectors with dimensions of 5×5×2 mm 3 and a microelectronics preamplifier. The different construction and technological aspects of probes designed for both application types are discussed. The probes were tested over a wide energy range. We obtained energy resolutions of 3.6, 4.9 and 14.5 keV at energies of 59.6, 122 and 662 keV, respectively, for the developed probe prototypes at room temperatu…
A portable telescope based on the ALIBAVA system for test beam studies
2013
Abstract A test beam telescope has been built using the ALIBAVA system to drive its data acquisition. The basic telescope planes consist of four XYT stations. Each station is built from a detector board with two strip sensors, mounted one in each side (strips crossing at 90°). The ensemble is coupled to an ALIBAVA daughter board. These stations act as reference frame and allow a precise track reconstruction. The system is triggered by the coincidence signal of the two scintillators located up and down stream. The telescope can hold several devices under tests. Each ALIBAVA daughter board is linked to its corresponding mother board. The system can hold up to 16 mother boards. A master board …
A radio frequency ring electrode cooler for low-energy ion beams
2004
We are investigating a new concept for ion confinement while buffer-gas-cooling low-energy ion beams. Instead of applying the well-established technique of Radio Frequency Quadrupoles (RFQs) where the ions are transversely confined by a quadratic-pseudo potential we are using a stack of thin ring electrodes supplied by an RF field (RF funnel) which creates a box-shaped potential well. In Monte Carlo simulations we have investigated the transmission behavior and cooling performance of the RF funnel. First experimental investigations with ion currents up to 20 nA revealed a promising transmission characteristic which qualifies the RF funnel as high-current cooler.
Determination of helium number densities in high-frequency electrodeless plasma
2010
Abstract The number densities of He first excited states 2 3 S 1 , 2 1 S 0 , 2 3 P 0,1,2 , and 2 1 P 0 were measured by absorption and self-absorption methods. The emission lines in the range 290–730 nm were used to determine the number densities of He metastable and resonant states of inductively coupled high-frequency electrodeless lamps filled with helium at pressure 0.1 Torr. The obtained number densities of helium metastable levels 2 3 S 1 and 2 1 S 0 are 2×10 12 and 3×10 11 cm −3 , respectively. For the 2 3 P 0,1,2 and 2 1 P 0 levels the determined number densities are ten times smaller than that of the metastable levels. Values of number densities from measurements using both method…
High-rate dead-time corrections in a general purpose digital pulse processing system
2015
The abilities on dead-time correction of a real-time digital pulse processing (DPP) system for high-rate high-resolution radiation measurements are presented. The DPP system, through a fast and slow analysis of the output waveform from radiation detectors, is able to perform an accurate estimation of the true input counting rate (ICR), a fine pulse height (energy) and shape (peaking time) analysis even at high ICRs.
The ATLAS tile calorimeter ROD injector and multiplexer board
2011
Abstract The ATLAS Tile Calorimeter is a sampling detector composed by cells made of iron-scintillator tiles. The calorimeter cell signals are digitized in the front-end electronics and transmitted to the Read-Out Drivers (RODs) at the first level trigger rate. The ROD receives triggered data from up to 9856 channels and provides the energy, phase and quality factor of the signals to the second level trigger. The back-end electronics is divided into four partitions containing eight RODs each. Therefore, a total of 32 RODs are used to process and transmit the data of the TileCal detector. In order to emulate the detector signals in the production and commissioning of ROD modules a board call…
Electron-pion discrimination with a scintillating fiber calorimeter
1990
Abstract We report on an experimental study of a variety of techniques for discriminating between (isolated) electrons and pions in a lead and scintillating fiber calorimeter without longitudinal segmentation. Using information from the lateral shower development, from a pre-shower detector, from the time structure of the signals, or from a combination of these we measure pion rejection factors of up to several thousand while maintaining electron efficiencies of 95% or higher.
Beam parameter stabilization for the P2 experiment at MESA
2020
Abstract The P2 Experiment at MESA (Mainz Energy-recovering Superconducting Accelerator) will measure the weak mixing angle via electron proton scattering at 155 MeV. The expected measured parity violation asymmetry will be about 40 ppb. This requires a high precision beam diagnostic and control system in order to minimize asymmetries that derive from helicity correlated fluctuations of the beam parameters. A control system for position and angle has been installed and tested at MAMI (Mainz Microtron) and the P2 precision requirements for determining the asymmetry and controlling the transverse beam parameters have been met.