Search results for "Silicon"
showing 10 items of 1391 documents
Characterization of alpha sources by Rutherford backscattering spectrometry
1996
Radioactive sources for alpha spectrometry are usually prepared by electrodeposition onto stainless steel backings (and sometimes heated). In earlier work, using the conventional method with passivated implanted planar silicon detectors for the measurements, several sources had been characterized in terms of various parameters by fitting the data of each spectrum to a certain mathematical function. In the present work, the Rutherford Backscattering Spectrometry (RBS) technique with a 1.6 MeV He+ beam was used to study the influence of those factors on the surface distribution and depth profiles of the thin radionuclide layers. Simulations of the measurements using the RUMP computer code wer…
Electron beam studies of light collection in a scintillating counter with embedded fibers
2021
The light collection of several fiber configurations embedded in a box-shaped plastic scintillating counter was studied by scanning with minimum ionizing electrons. The light was read out by silicon photomultipliers at both ends. The light yield produced by the 855-MeV beam of the Mainz Microtron showed a strong dependence on the transverse distance from the beam position to the fibers. The observations were modeled by attributing the collection of indirect light inside of the counter and of direct light reaching a fiber to the total light yield. The light collection with fibers was compared to that of a scintillating counter without fibers. These studies were carried out within the develop…
Planar channeling experiments with electrons at the 855MeV Mainz Microtron MAMI
2008
Abstract Planar channeling has been studied for silicon single crystals at a beam energy of 855 MeV at the Mainz Microtron MAMI. Complex channeling patterns were observed from which the crystal orientation can unambiguously be determined. Photon spectra at (1 0 0), (1 1 0) and (1 1 1) planar channeling were recorded with a 10″ × 10″ NaI detector. The planar (1 1 0) channeling process has been studied as function of the crystal thickness in the range between 7.9 and 270 μm from which a dechanneling length of 18.0 μm and the thickness dependent rechanneling lengths were deduced, employing solutions of the Fokker–Planck equation. A signal derived from high energy bremsstrahlung exhibits a char…
Breakthrough in pulse-shape based particle identification with silicon detectors
2000
Identification of charged particles is an important method in nuclear spectroscopy. We have achieved a major breakthrough that makes the pulse-shape discrimination (PSD) method with a single solid-state detector comparable to and sometimes better than the traditional telescope technique. By using rear-side injection in over-biased surface barrier n-type Si detectors made from homogeneously doped n-TD silicon, and extracting the pulse-shape information already at the preamplifier level we have reached improved Z and even A discrimination over a wide dynamic range. Previously good separation with the PSD technique required a major degradation of time resolution and inferior energy resolution.…
α-decay properties ofPb181
1996
The isotope {sup 181}Pb was produced in {sup 92}Mo bombardments of {sup 90}Zr and, together with other reaction products, was passed through a recoil mass separator and implanted in a double-sided silicon strip detector for {alpha}-particle assay. The half-life and energy of the main {sup 181}Pb {alpha} transition were determined to be 45 (20) ms and 7065 (20) keV, respectively. This {sup 181}Pb {ital E}{sub {alpha}} agrees with one previously measured value [7044 (15) keV], but not with the one [7211 (10) keV] used as input to the 1993 Atomic Mass Evaluation. The 6180-keV {alpha} transition assigned to {sup 181}Tl by Bolshakov {ital et} {ital al}. was observed, but the 6566-keV {alpha} par…
Digital pulse-shape analysis with a TRACE early silicon prototype
2014
[EN] A highly segmented silicon-pad detector prototype has been tested to explore the performance of the digital pulse shape analysis in the discrimination of the particles reaching the silicon detector. For the first time a 200 tun thin silicon detector, grown using an ordinary floating zone technique, has been shown to exhibit a level discrimination thanks to the fine segmentation. Light-charged particles down to few MeV have been separated, including their punch-through. A coaxial HPGe detector in time coincidence has further confirmed the quality of the particle discrimination. K.; 2014 Elsevier B.V. All rights reserved
Experimental investigation of the 02+ band in Sm154 as a β-vibrational band
2014
Abstract A study of Sm 154 through γ -ray and internal conversion electron coincidence measurements was performed using the Silicon And GErmanium spectrometer (SAGE). An upper limit for the ρ 2 ( E 0 ; 2 2 + → 2 1 + ) and measurement of the ρ 2 ( E 0 ; 4 2 + → 4 1 + ) monopole transitions strengths were determined. The extracted transition strength for each is significantly lower than that predicted by either the Bohr and Mottelson β -vibration description or the interacting boson model. Hence, the long standing interpretation of these states as a collective band built on the 0 2 + state, which is conventionally assigned as a Bohr and Mottelson β vibration is questionable.
A dedicated decay-spectroscopy station for the collinear resonance ionization experiment at ISOLDE
2013
A newdecay-spectroscopystation(DSS)has been developed to be coupled to the collinear resonance ionization spectroscopy (CRIS) beam line at CERN-ISOLDE. The system uses a rotatable wheel with ten 20 mg=cm2 carbon foils as beam implantation sites for the efficient measurement of charged decay products. Silicon detectors are placed on either side of the carbon foil in an optimal geometry to cover a large solid angle for detecting these charged particles. In addition to the silicon detectors at the on-beam axis position, a second pair of off-beam axis detectors are placed at the wheel position 108 deg. away, allowing longer-lived species to be studied. Up to three high purity germanium detector…
The ISOLDE Silicon Ball
2003
The development of new spectroscopy devices with the capability of detecting charged particles and precisely determining their energy, angular distribution and nature has become one of the requirements for the investigation of weakly bound nuclei close to the particle driplines. With this aim the ISOLDE Silicon Ball is under construction. It is a charged particle spectroscopy device allowing for the investigation of the exotic nuclei produced at ISOLDE and at other similar facilities. Very high geometrical efficiency and broad energy range coverage are required. In order to allow for particle identification the simultaneous use of the Time of Flight and Pulse Shape Discrimination techniques…
Radiation hardness of Czochralski silicon, Float Zone silicon and oxygenated Float Zone silicon studied by low energy protons
2004
Abstract We processed pin-diodes on Czochralski silicon (Cz-Si), standard Float Zone silicon (Fz-Si) and oxygenated Fz-Si. The diodes were irradiated with 10, 20, and 30 MeV protons. Depletion voltages and leakage currents were measured as a function of the irradiation dose. Additionally, the samples were characterized by TCT and DLTS methods. The high-resistivity Cz-Si was found to be more radiation hard than the other studied materials.