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1995, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
The characteristics and performances of a large time of flight detector which is composed by two scintillator barrels, installed between the poles of an axial field magnet as part of the OBELIX spectrometer, are described. The associated electronics, data acquisition system and analysis technique used in the system are discussed in details. The importance of the detector for trigger purposes and for the comprehension of the full event is shown.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2010
The ''Time-Of-Flight'' (TOF) system of the AMS-02 superconducting spectrometer, to be installed in the ISS International Space Station, consists of four layers of plastic scintillation counters. During the precursor mission AMS-01 (June 1998), a similar system successfully operated in space for 10 days. However, the AMS-02 TOF had to be redesigned taking into account the more stringent mass and power constraints of the AMS-02 detector. The main characteristics of the new TOF system are (a) capability to stand the high fringing field of AMS-02 superconducting magnet; (b) high redundancy of electronic components for unmanned operation of at least three years in the space station; (c) capability to operate in the space environment on the ISS. Counters and electronics have been extensively tested before the installation in the spectrometer.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1999
The system of plastic scintillator counters for the AMS experiment is described. The main characteristics of the detector are: (a) large sensitive area (four 1.6 m planes) with small dead space; (b) low-power consumption (150 W for the power and the read-out electronics of 336 PMs); (c) 120 ps time resolution.
Study Through Geant4, for Time Resolution Characterization of Different Detectors Arrays Coupled with Two Sipms, As a Function of: The Scintillator Plastic Material, its Volumetric Dimensions and the Location of the Radiation Emission Source, 2021
The high time resolution detectors are relevant in those experiments or simulations were the particles to detect, have a very short time of flight (TOF), and due this it´s required that the detections times are ranged between ns. & ps. Using Geant4 software, it was made thirty simulations of coupled detectors to plastic scintillators with two silicon photomultipliers (SiPMs) located on the scintillator's central sides. To characterize the time resolution, it was required to quantify the optical photons that reach the Score in a certain time, which are generated by muons on the surface of the plastic scintillator. Different configurations of muon beams were simulated at energy of 1 GeV, to interact with the configuration of the scintillator material of its corresponding arrangement. The simulations were made varying three parameters: the scintillator material "BC404 & BC422", its size, and the location of the radiation source. Fifteen simulations correspond to BC404 material & fifteen simulations to BC422 material respectively. The first five simulations consisted in varying the scintillator's volumetric size and collocate the muons beam guided randomly distributed over it, the next five simulations differentiate from setting up a directly centered beam, and the last five simulations for guide the beam on the left lower corner of each scintillator. The best time resolution achieved was σ= 8.67 +/− 0.26 ps., reported by the detector with BC422 scintillator material which has a volume of 20x20x3 mm 3 .
Pulse height and time characteristics of the CsI(Tl)-Si(PIN) scintillation detector have been studied and compared with the other scintillation detectors such as BaF2 and BGO. Energy Resolution for different radiations of differing energies gamma- rays emitted form 137 Cs and 60 Co and alpha particles from the 241 Am and 239 Pu is determined to be 6.41% & 6.24%(75 keV and 83 keV) for the gamma rays of energy 1.17 MeV & 1.33 MeV respectively emitted by 60 Co source. For the Am-Pu source which emits alpha particles of energies 5.155 MeV & 5.486 MeV the resolutions are 2.77% & 2.71%(143 keV and 149 keV) respectively. The time response of the detector has also been investigated and the time resolution for γ-rays is determined to be 170ns.
Nuclear Instruments and Methods, 1974
The study of time resolutmn as a tunctmn of the mggerlng windows between 25 keV and 200 keV were normahzed and fractmn C/R for the scmtdlatmn counter consisting of an compared w~th the calculated curve according to Hyman XP1021 photomulnpher and a 1 25 cmx 0 2 cm NE111 scm-theory The good fit of the theoretical curve to the experimental tlllator was performed The scintillator was lrradmted by fl-rays one shows that Hyman theory describes well the riming propemes of 6°Co The C/R curves measured for some selected energy of the plastic scmtfllatmn counters
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2014
In isochronous mass spectrometry (IMS) established in heavy-ion storage rings the revolution times of the stored secondary ions should be independent of their velocity spread. However, this isochronous condition is fulfilled only in first order and in a small range of revolution times. To correct for the nonisochronicity an additional measure of the velocity or magnetic rigidity of each stored ion is required. For this purpose two new time-of-flight (TOF) detectors were installed in a straight section of the experimental Cooler Storage Ring CSRe in Lanzhou. The performance of the new time-of-flight (TOF) detectors, which is crucial for the achievable efficiencies and mass resolving power, was significantly improved. The time resolution of the TOF detector in offline tests was s ¼ 18:5 7 2 ps. The detector setup was put into operation with a stable beam of 78 Kr.
Ultrahigh- and High-Speed Photography, Videography, and Photonics '93, 1993
A time-, position-and energy-resolved soft x-ray (100-500 eV) diagnostic is being developed for PBFA II target experiments. The diagnostic provides measurements of hydrodynamic motion and thermal gradients in light-ion fusion targets. A slit-image of the source is imprinted onto thin sheets (20l.tm) of organic scintillator to create a one-dimensional image. The scintillator light is then proximity-coupled to a linear array of fiber-optics that transports the light to a streak camera that is operated without an intensifier. The streak camera output is recorded on a charge-coupled-device (CCD) camera. We are characterizing the spatial and temporal resolutions of the systems. This is done by collecting data from as many as 90 individual fibers and correcting for variations in throughput and the effects of spatial resolution to roughly 5% standard deviation in their relative throughput. Spatial resolution of these systems at the source is approximately 0.4 mm. Timing resolution is nominally 2 ns and it is limited primarily by the scintillator response and dispersion in the 50-m-long fiber array. We describe the measurement techniques and the results of the characterization.
Radiation …, 1995
We have developed a bench-top pulsed X-ray system for measuring scintillation properties of compounds in crystalline or powdered form. The source is a light-excited X-ray tube that produces 40 X-ray photons (mean energy 18.5 keV) per steradian in each 100 pps fwhm pulse. The ...
Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray, 2012
The Large Observatory for X-ray Timing (LOFT) is one of the four candidate ESA M3 missions considered for launch in the 2022 timeframe. It is specifically designed to perform fast X-ray timing and probe the status of the matter near black holes and neutron stars. The LOFT scientific payload is composed of a Large Area Detector (LAD) and a Wide Field Monitor (WFM). The LAD is a 10 m 2 -class pointed instrument with 20 times the collecting area of the best past timing missions (such as RXTE) over the 2-30 keV range, which holds the capability to revolutionize studies of X-ray variability down to the millisecond time scales. Its ground-breaking characteristic is a low mass per unit surface, enabling an effective area of ~10 m 2 (@10 keV) at a reasonable weight. The development of such large but light experiment, with low mass and power per unit area, is now made possible by the recent advancements in the field of large-area silicon detectors -able to time tag an X-ray photon with an accuracy <10 μs and an energy resolution of ~260 eV at 6 keV -and capillary-plate X-ray collimators. In this paper, we will summarize the characteristics of the LAD instrument and give an overview of its capabilities.
Epj Web of Conferences, 2013
A fast-decay and low-afterglow liquid scintillator was developed for the fast ignition experiment at the Institute of Laser Engineering (ILE). The liquid scintillator was coupled to a gated photomultiplier (PMT), and the gating performance under high-intensity-rays was experimentally checked. In 2010, a detector with a high detection efficiency of 10 −4 was developed and installed in this experiment. The neutron yield in the fast heating experiment was successfully measured using this detector.
2020
Fast timing detectors are an essential element in the experimental setup for time-of-flight (ToF) mass measurements of unstable nuclei. We have upgraded the scintillator detectors used in experiments at the National Superconducting Cyclotron Laboratory (NSCL) by increasing the number of photomultiplier tubes that read out their light signals to four per detector, and characterized them in a test experiment with 48Ca beam at the NSCL. The new detectors achieved a time resolution ( σ ) of 7.5 ps. We systematically investigated different factors that affect their timing performance. In addition, we evaluated the ability of positioning the hitting points on the scintillator using the timing information and obtained a resolution ( σ ) below 1 mm for well-defined beam spots.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2002
The proposed Hall D detector at Jefferson Lab will have a time-of-flight detector composed of long and narrow scintillator bars. We have evaluated the time resolution of two bar prototypes in particle beams at the Institute for High Energy Physics in Protvino, Russia. The bars are 2:0 m long and have square cross-sections of size 2.5 and 5:0 cm 2 : In this paper, we present results on how the time resolution of each of these bars depends on the entry position of the beam into the scintillator, on the material used for scintillator wrapping and on the phototube used for the readout. r 2002 Elsevier Science B.V. All rights reserved. PACS: 29.40.Mc Keywords: Hall D; Time of flight; Particle identification 0168-9002/02/$ -see front matter r 2002 Elsevier Science B.V. All rights reserved. PII: S 0 1 6 8 -9 0 0 2 ( 0 1 ) 0 1 7 9 8 -3
2019
Lifetime of a nuclear excited state is one of the main observables in the nuclear structure studies. The lifetime determines the reduced electromagnetic transition probability which is used to be compared with predictions derived by using theoretical nuclear structure models and thus provides an essential nuclear observable to test the model dependent structure of the nuclear excited states. There are different ways to measure lifetime of an excited state and their use depends on the magnitude of the value we are interested in. In this research we focused on the - coincidence technique and its implementation with the scintillation detectors, especially the inorganic LaBr3(Ce) scintillators. In the first part of this work, the main characteristics and components of a scintillator detector, together with the main pick-off methods in timing measurements, are discussed. In the second part, timing performance and some important linked properties of seven LaBr3(Ce) scintillators of two ...
Instruments and Experimental Techniques, 2000
The HADES spectrometer and a time-of-flight detector based on long-sized (50-250 cm) scintillation counters are described. The detector is designed for identification of electrons, pions, and protons with momenta of 0. I-1.5 GeV/c at a flight distance of 220-250 cm. The operating conditions are analyzed, and the requirements to the detector and counter design are formulated. The design of the counters and their arrangement in the spectrometer are considered. The results of experimental studies of such characteristics of long counters as the light attenuation length in a scintillator and temporal and spatial resolutions, depending on the kx:ation of the point of the particle's hit on the counter, are presented. Analysis of the data has shown that the main factor determining the spatial resolution of long counters is the quality of the polishing of the side faces of the scintillators, which determines the effective (averaged over the scintillator side surfaces) coefficient of total internal reflection R. It is shown that, for R > 0.99, it is quite possible to achieve temporal and spatial resolutions of 100 ns and 2-3 cm, respectively, for scintillators with a length of up to 250 cm and a cross section of 1-20 cm 2. Foreign and Russian photomultipliers were used in the counters.
Proceedings of 35th International Cosmic Ray Conference — PoS(ICRC2017)
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004
A high precision, time-of-flight hodoscope has been constructed to analyse the secondary pion beam at GSI, Darmstadt. The hodoscope comprises three scintillator planes with the individual scintillator rods read out by photomultipliers in both ends. A new active base of the emitter follower type has been developed for stabilization of voltages at the last dynodes of the photomultiplier. The time resolution of this system was found to be sp150 ps for counting rates up to 2 MHz.
Chinese Physics C, 2017
Plastic scintillation detectors for Time-of-Flight (TOF) measurements are almost essential for event-byevent identification of relativistic rare isotopes. In this work, a pair of plastic scintillation detectors of 50 × 50 × 3 t mm 3 and 80 × 100 × 3 t mm 3 have been set up at the external target facility (ETF), Institute of Modern Physics. Their time, energy and position responses are measured with 18 O primary beam at 400 MeV/nucleon. After the off-line walk-effect and position corrections, the time resolution of the two detectors are determined to be 27 ps (σ) and 36 ps (σ), respectively. Both detectors have nearly the same energy resolution of 3% (σ) and position resolution of 2 mm (σ). The detectors have been used successfully in nuclear reaction cross section measurements, and will be be employed for upgrading RIBLL2 beam line at IMP as well as for the high energy branch at HIAF.
Journal of Instrumentation, 2016
Proceedings of International Europhysics Conference on High Energy Physics — PoS(HEP2005), 2007
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