Search

We report on activities using a pulsed neutron facility consisting of an electron linear accelerator, a water-cooled Ta target with a water moderator, and a 12 m time-of-flight path. It is possible to measure neutron total cross sections in the neutron energy range from 0.01 eV to a few hundred eV by using the neutron time-of-flight method; photo-neutron cross sections can also measure by using the bremsstrahlung from the electron linac. A 6LiZnS(Ag) glass scintillator was used as a neutron detector. The neutron flight path from the water-cooled Ta target to the neutron detector was 12.1 m. In this paper, we report total cross sections of Nb and also resonance parameters obtained using the SAMMY fitting program. The present results are compared with the previous experimental results and the evaluated data in ENDF/B-VII. We also report on the mass-yield distribution of fission products in the 2.5-GeV bremsstrahlung-induced fission of natPb and 209Bi measured at the 2.5-GeV electron linac using a recoil catcher and an off-line γ-ray spectrometric technique. [ABSTRACT FROM AUTHOR]

We present here a Phoswich scintillator design to achieve both high resolution gamma ray detection, and good efficiency for high energy protons. There are recent developments of new high resolution scintillator materials. Especially the LaBr3(Ce) and LaCl3(Ce) crystals have very good energy resolution in the order of 3% for 662 keV gamma radiation. In addition, these materials exhibit a very good light output (63 and 32 photons/keV respectively). A demonstrator detector in the form of an Al cylinder of 24 mm diameter and a total length of 80 mm with 2 mm wall thickness, containing a LaBr3(Ce) crystal of 20 mm diameter and 30 mm length directly coupled to a LaCl3(Ce) crystal of 50 mm length, and closed with a glass window of 5 mm, was delivered by Saint Gobain. To the glass window a Hamamatsu R5380 Photomultiplier tube (PMT) was coupled using silicon optical grease. [ABSTRACT FROM AUTHOR]

The PEANUT experiment was designed to study neutrino interactions in the few GeV range using the NuMi beam at Fermilab. The detector uses a hybrid technique, being made of nuclear emulsions and scintillator trackers. Emulsion films act as a tracking device and they are interleaved with lead plates used as neutrino target. The detector is designed to reconstruct the topology of neutrino interactions at the single particle level. We present here the full reconstruction and analysis of a sample of 147 neutrino interactions occurred in the PEANUT detector and the measurement of the quasi-elastic, resonance and deep-inelastic contributions to the total charged current cross-section. This technique could be applied for the beam monitoring for future neutrino facilities. [ABSTRACT FROM AUTHOR]

MINERvA is a precision neutrino experiment designed to improve our understanding of the neutrino-nucleus interaction. The experiment uses a fully active scintillation detector to allow full event reconstruction and includes nuclear targets helium, water, carbon, iron and lead. Here we describe the first steps in measuring lead to iron to carbon cross section ratios. [ABSTRACT FROM AUTHOR]

We report measurements of charged current inclusive and quasielastic interactions of muon neutrinos on carbon with an average energy of 0.8 GeV by SciBooNE experiment at Fermilab. These two results are complementary to understand the neutrino-nuclear interaction in the few-GeV region with effects of final state interactions. [ABSTRACT FROM AUTHOR]

Determination of the quasi-elastic scattering cross-section over a broad range of neutrino energies, nuclear targets and Q2 is a primary goal of the MINERvA experiment. We present preliminary comparisons of data and simulation in a sample rich in νμp→μ+n events from approximately one eighth of the total ν events collected by MINERvA to date. We discuss future plans for quasi-elastic analyses in MINERvA. [ABSTRACT FROM AUTHOR]

This paper covers possible detector options suitable at future neutrino facilities, such as Neutrino Factories, Super Beams and Beta Beams. The Magnetised Iron Neutrino Detector (MIND), which is the baseline detector at a Neutrino Factory, will be described and a new analysis which improves the efficiency of this detector at low energies will be shown. Other detectors covered include the Totally Active Scintillating Detectors (TASD), particularly relevant for a low energy Neutrino Factory, emulsion detectors for tau detection, liquid argon detectors and megaton scale water Cherenkov detectors. Finally the requirements of near detectors for long-baseline neutrino experiments will be demonstrated. [ABSTRACT FROM AUTHOR]

We study anisotropy of ultra-high energy cosmic ray (UHECR) events collected by the Telescope Array detector in the first 2 years of operation. We find that the self-correlation function of UHECR at energies larger 10 and 40 EeV shows no significant small-scale clustering. The events with energy E>57 EeV do not significantly correlate with the positions of the nearby active galactic nuclei (AGN): of observed 15 events 6 are found within 3.7° from an AGN, while 3.6 are expected for a random distribution (16% chance probability). We also check the event sets with energies E>40 EeV and E>57 EeV for correlations with the large scale structure (LSS) of the Universe. We find that both data sets are compatible with the LSS model at the 95% confidence level. [ABSTRACT FROM AUTHOR]

The Telescope Array (TA) experiment is the only ultra high energy cosmic ray observatory in the northern hemisphere. In addition, it will be the world's first air shower detector to be directly calibrated by an on-site accelerator beam. For wider and deeper understanding of cosmic rays by via high precision measurements, we have undertaken the study of extension plans for TA. One extension plan will extend the sensitive energy range of TA down to 1017 eV. A second plan would extend of the aperture area of the SD array. These plans are described in this note. [ABSTRACT FROM AUTHOR]

We measure arrival directions, energies and mass composition of ultra-high energy cosmic rays with air fluorescence detector telescopes. The longitudinal profile of the cosmic ray induced extensive air shower cascade is imaged on focal plane of the telescope camera. Here, we show an event reconstruction method to obtain the primary information from data collected by the Telescope Array Fluorescence Detectors. In particular, we report on an 'Inverse Monte Carlo (IMC)' method in which the reconstruction process searches for an optimum solution via repeated Monte Carlo simulations including characteristics of all detectors, atmospheric conditions, photon emission and scattering processes. [ABSTRACT FROM AUTHOR]

UV fluorescence light generated by an air shower is scattered and lost along the path of transmission to the telescope. The main scattering processes are Rayleigh scattering by molecules and scattering by aerosols in an atmosphere. In the Telescope Array Experiment, we make use of LIDAR (LIght Detection And Ranging), which observes the back-scattered light of laser. The LIDAR system is operated before the beginning and after the end of an FD observation, twice a night. The typical transparency of aerosols on clear night is obtained two years observation from September, 2007. The extinction coefficient of aerosols (αAS) at ground level are 0.040-0.013+0.036 km-1. The dependence of typical aerosols on height above ground level (1450 m a.s.l.) can be express by two exponential components as following: αAS(h) = 0.021 exp(-h/0.2)+0.019 exp(-h/1.9). The atmospheric transparency measured with the LIDAR system in TA site is discussed in this paper. [ABSTRACT FROM AUTHOR]

The Central Laser Facility (CLF) is the laser device which shoots the vertical laser. CLF is located at the Center of the Telescope Array (TA) experiment site. The TA has three fluorescence detectors. CLF is equidistant from three FD stations. We made the CLF simulation using the same program as the cosmic-ray simulation. Using the CLF simulation, we reconstruct the energy shot by the CLF. In this paper, we describe some results of CLF reconstruction comparing the difference of reconstructed energy between two fluorescence telescopes. [ABSTRACT FROM AUTHOR]

The accuracies in determination of air shower parameters such as longitudinal profiles or primary energies with the fluorescence detection technique are strongly dependent on atmospheric conditions of the molecular and aerosol components. Moreover, air fluorescence photon yield depends on the atmospheric density, and the transparency of the air for fluorescence photons depends on the atmospheric conditions from EAS to FDs. In this paper, we describe the atmospheric monitoring system in the Telescope Array (TA experiment), and the impact of the atmospheric conditions in air shower reconstructions. The systematic uncertainties of the determination of the primary cosmic ray energies and of the measurement of depth of maximum development (Xmax) of EASs due to atmospheric variance are evaluated by Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

The mesurement of the extensive air shower using the fluorescence detectors (FDs) is affected by the condition of the atmosphere. In particular, FD aperture is limited by cloudiness. If cloud exists on the light path from extensive air shower to FDs, fluorescence photons will be absorbed drastically. Therefore cloudiness of FD's field of view (FOV) is one of important quality cut condition in FD analysis. In the Telescope Array (TA), an infrared (IR) camera with 320×236 pixels and a filed of view of 25.8°×19.5° has been installed at an observation site for cloud monitoring during FD observations. This IR camera measures temperature of the sky every 30 min during FD observation. IR camera is mounted on steering table, which can be changed in elevation and azimuthal direction. Clouds can be seen at a higher temperature than areas of cloudless sky from these temperature maps. In this paper, we discuss the quality of the cloud monitoring data, the analysis method, and current quality cut condition of cloudiness in FD analysis. [ABSTRACT FROM AUTHOR]

We report the development of a 'hybrid trigger' system for the fluorescence detectors (FDs) and the surface detectors (SDs) in the Telescope Array (TA) experiment. It is shown from our Monte-Carlo studies that geometry determination accuracies of monocular FD events are significantly improved using SD information (position at the ground level, timing of arrival, etc...). On the other hand, in a lower energy event, the trigger efficiency of SD for lower energy showers is smaller than that of FD. Therefore no SD information is available for events with energies below 1018.5 eV taken with the TA original data acquisition system. In order to collect the small SD signals, we developed an FD-driven SD triggering system: this introduces an external triggering scheme to the TA-SD using triggering signals from FD. We present the design of the system, installation and the operational stabilities in TA observation from October 2010. [ABSTRACT FROM AUTHOR]

Ultra-high-energy cosmic rays (UHECRs) refer to cosmic rays with energy above 1018 eV. UHECR experiments utilize simulations of extensive air shower to estimate the properties of UHECRs. The Telescope Array (TA) experiment employs the Monte Carlo codes of CORSIKA and COSMOS to obtain EAS simulations. In this paper, we compare the results of the simulations obtained from CORSIKA and COSMOS and report differences between them in terms of the longitudinal distribution, Xmax-value, calorimetric energy, and energy spectrum at ground. [ABSTRACT FROM AUTHOR]

The Telescope Array (TA) is the largest detector in the northern hemisphere to explore the origin of ultra-high energy cosmic rays (UHECR). Here we present the status and preliminary results from the TA experiment. These include the spectra measured by three different methods, composition using the depth of shower maximum, and anisotropy using arrival directions. [ABSTRACT FROM AUTHOR]

We search for ultra-high energy photons by analyzing geometrical properties of shower fronts of events registered by the Telescope Array surface detector. By making use of an event-by-event statistical method, we derive an upper limit on the absolute flux of primary photons with energies above 1019 eV. [ABSTRACT FROM AUTHOR]

The Telescope Array (TA) experiment detects air showers induced by extremely high energy cosmic rays in the middle west of Utah, USA. The TA experiment consists of two different types of detector such as atmospheric fluorescence detectors (FDs) and surface array particle detectors (SDs). The SD observation started in March 2008. This paper describes the search for the small scale clusters from 850-days TA SD data by auto-correlation method for several energy thresholds. As a result, there is no indication of small scale clusters by TA SD. [ABSTRACT FROM AUTHOR]

Analysis techniques in LHCf are presented, in which all techniques are required to have a high resolution and efficiency in order to overcome the severe situation, small lateral aperture and longitudinally short length of the detector. In this paper, methods for reconstructing an energy of electromagnetic shower are discussed following the data flow of measured data and Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

The GSO scintillator has a very excellent radiation resistance, fast decay time and large amounts of light yield. Because of these features, GSO will be used to upgrade the current LHCf detector. We examined the features of GSO by using heavy ion beam at Heavy Ion Medical Accelerator in Chiba (HIMAC) Japan. The linearity of PMT R7400 for the large light yield of GSO with a 132Xe beam and the radiation hardness with a 12C beam were measured. As a result, GSO scintillator showed a good linearity up to the signal corresponding to 6 TeV EM-shower maximum in the LHCf detector, and a good radiation hardness up to 7×105 Gy. For the LHCf Arm1 detector, small scaled GSO crystals (GSO bars), have been fabricated for the position determination detector. 5 GSO bars have been manufactured and its performance have been evaluated using 12C beam. Its light yield and position dependency have been evaluated. [ABSTRACT FROM AUTHOR]

The COsmic ray Research and Education Array (COREA) collaboration has installed an array of six detector stations at two high schools in and near Seoul, Korea for measurement of air-shower events from high-energy cosmic rays. Three stations are installed at each site, where each station consists of four plastic scintillation detectors covering an area of 2m2. In this presentation, we report the currenst status of the COREA project, describing the experimental equipment and measurement of coincident events. [ABSTRACT FROM AUTHOR]

This work presents the first results obtained in the 'Assembly and characterization of position sensitive detectors composed of scintillators coupled to silicon photomultipliers' project. The development of new x and γ radiation detectors have found several technological applications, especially in medical physics, where γ detectors that can be used in high intensity magnetic field are of particular importance. The experimental setup consisted of coupling of two silicon photomultipliers (SiPM) to the small sides of a 3×3×100 mm3 scintillator and the coupling of one SiPM to one of the small sides of a 3×3×10 mm3 scintillator. We found that the detectors used in this study presented an energy resolution that is in agreement with those observed in scintillators of the same family coupled to conventional photomultipliers. Besides that, there is a strong correlation between the difference of the light intensity in both SiPMs of the long detector and the position of the γ source. The results confirm the great potential of application of such detectors. [ABSTRACT FROM AUTHOR]

The diffractive physics program for the ATLAS experiment with an emphasis on the central exclusive production is discussed. The key point in this discussion is the need for an unambiguous experimental definition of diffractive signature which would be acceptable and reproducible by theorists. Recent ATLAS results from samples enhanced in diffraction contribution underline this need. [ABSTRACT FROM AUTHOR]

We discuss some aspects of a new sub-detector for the ALICE experiment at the LHC. This detector would enhance the capabilities of ALICE to study several topics of diffractive as well as of photon induced physics. It consists of four stations of scintillator pads that would tag the diffractive gap more efficiently. [ABSTRACT FROM AUTHOR]

CANDLES is the project to search for neutrinoless double beta (0νββ) decay of 48Ca by using CaF2 scintillators. The observation of 0νββ decay will prove the existence of massive Majorana neutrinos. Expected performances and current status of the CANDLES system are described. [ABSTRACT FROM AUTHOR]

Argon is a strong scintillator and an ideal target for Dark Matter detection; however 39Ar contamination in atmospheric argon from cosmic ray interactions limits the size of liquid argon dark matter detectors due to pile-up. Argon from deep underground is depleted in 39Ar due to the cosmic ray shielding of the earth. In Cortez, Colorado, a CO2 well has been discovered to contain approximately 600 ppm of argon as a contamination in the CO2. We first concentrate the argon locally to 3% in an Ar, N2, and He mixture, from the CO2 through chromatographic gas separation, and then the N2 and He will be removed by continuous distillation to purify the argon. We have collected 26 kg of argon from the CO2 facility and a cryogenic distillation column is under construction at Fermilab to further purify the argon. [ABSTRACT FROM AUTHOR]

The development of BiPo detectors is dedicated to the measurement of extremely high radiopurity in 208Tl and 214Bi for the SuperNEMO double beta decay source foils. A modular prototype called BiPo-1 with 0.8 m2 of sensitive surface area has been running in the Modane Underground Laboratory since February 2008. The goal of BiPo-1 is to measure the different components of the background and in particular the surface radiopurity of the plastic scintillators that make up the detector. The first phase of data collection has been dedicated to the measurement of the radiopurity in 208Tl. After more than one year of background measurement a surface activity of the scintillators of A(208Tl) = 1.5 μBq/m2 is reported here. Given this level of background, a larger BiPo3 detector having 3.25 m2 of active surface area, will able to qualify the radiopurity of the SuperNEMO selenium double beta decay foils with the required sensitivity of A(208Tl)<3-4 μBq/kg (90% C.L.) with a six month measurement. This detector is actually under construction and will be installed in the Canfranc Underground Laboratory mid 2011. [ABSTRACT FROM AUTHOR]

Diffractive and photon induced physics is a research area with a remarkable discovery potential at the LHC. ALICE has started a program to exploit its unique capabilities to study the subject in both proton-proton and heavy ion collisions. We discuss some aspects of a new sub-detector for the ALICE experiment at the LHC. This detector would enhance the performance of ALICE to address some relevant topics on this matter. It consists of four stations of scintillator pads that would tag the diffractive gap more efficiently. [ABSTRACT FROM AUTHOR]

The NA48/2 experiment at CERN [1] collected ∼18·109 charged kaon decays during the years 2003/4. Along with the primary goals of the collaboration, i.e. the measurement of the CP-violating asymmetry in the K±→π±π+π- and K±→π±π0π0 decays thanks to the simultaneous collection of K+ and K- events, the collected data allowed to perform many other interesting analyses. In this paper two independent measurements of ππ scattering lengths will be reviewed, using NA48/2 data from the K±→e±νπ+π- decay and from the cusp effect in K±→π±π+π- respectively. [ABSTRACT FROM AUTHOR]

KASCADE-Grande, an extension of the former KASCADE experiment, is a multi-component Extensive Air Shower (EAS) experiment located in Karlsruhe Institute of Technology (Campus North), Germany. An important observable for analyzing the EAS is the lateral density of charged particles in the intrinsic shower plane. This observable is deduced from the basic information provided by the Grande scintillators-the energy deposit-first in the observation plane, by using a Lateral Energy Correction Function (LECF), then in the intrinsic shower plane, by applying an adequate mapping procedure. In both steps azimuthal. [ABSTRACT FROM AUTHOR]

A short introduction summarizes the experimental high energy field of neutrino oscillations and the oscillation notations. Then the results obtained by experiments on atmospheric neutrino oscillations are summarized and discussed. At the beginning of the new century a number of long baseline neutrino beams became available. The results obtained by different long baseline neutrino oscillation experiments are considered, including the first possible event νμ→ντ in appearance mode. Finally conclusions and perspectives are discussed. [ABSTRACT FROM AUTHOR]

An experiment to search for 2b processes in 106Cd with the help of 106CdWO4 crystal scintillator (mass of 215 g), enriched in 106Cd up to 66%, is in progress at the Gran Sasso National Laboratories of the INFN (Italy). After 1320 h of data taking, limits on double beta processes in 106Cd have been established on the level of 1019-1020 yr, in particular (all the results at 90% C.L.): T1/2(0ν2[variant_greek_epsilon])>3.6×1020 yr, T1/2(2ν[variant_greek_epsilon]β+)>7.2×1019 yr, and T1/2(2ν2β+)>2.5×1020 yr. Resonant 0ν2[variant_greek_epsilon] processes have been restricted as T1/2(0ν2K)>1.4×1020 yr and T1/2(0νLK)>3.2×1020 yr. A possible resonant enhancement of the 0ν2[variant_greek_epsilon] processes is estimated in the framework of the QRPA approach. [ABSTRACT FROM AUTHOR]

A parallel image detection system using an annular pupil for electron optics were developed to realize an increase in the depth of focus, aberration-free imaging and separation of amplitude and phase images under scanning transmission electron microscopy (STEM). Apertures for annular pupils able to suppress high-energy electron scattering were developed using a focused ion beam (FIB) technique. The annular apertures were designed with outer diameter of o\ 40 μm and inner diameter of o\32 μm. A taper angle varying from 20° to 1° was applied to the slits of the annular apertures to suppress the influence of high-energy electron scattering. Each azimuth angle image on scintillator was detected by a multi-anode photomultiplier tube assembly through 40 optical fibers bundled in a ring shape. To focus the image appearing on the scintillator on optical fibers, an optical lens relay system attached with CCD camera was developed. The system enables the taking of 40 images simultaneously from different scattered directions. [ABSTRACT FROM AUTHOR]

This work is focused on a development of a compact fast scintillation detector suitable for Mössbauer spectroscopy (low energy X-ray/γ-ray detection) where high counting rates are inevitable. Optimization of this part was necessary for a reliable function, better time resolution and to avoid a detector pulses pile-up effect. The pile-up effect decreases the measurement performance, significantly depends on the source activity and also on the pulse duration. Our new detection unit includes a fast scintillation crystal YAP:Ce, an R6095 photomultiplier tube, a high voltage power supply socket C9028-01 assembly, an AD5252 digital potentiometer with an I2C interface and an AD8000 ultra fast operation preamplifier. The main advantages of this solution lie in a short pulse duration (less than 200 ns), stable operation for high activities, programmable gain of the high voltage supply and compact design in the aluminum housing. [ABSTRACT FROM AUTHOR]

Gadolinium loaded liquid scintillator (Gd-LS) is an excellent target material for reactor antineutrino experiments. Ideal Gd-LS should have long attenuation length, high light yield, long term stability, low toxicity, and should be compatible with the material used to build the detector. We have developed a new Gd-LS recipe in which carboxylic acid 3,5,5-trimethylhexanoic acid is used as the complexing ligand to gadolinium, 2,5-diphenyloxazole (PPO) and 1,4-bis[2-methylstyryl]benzene (bis-MSB) are used as primary fluor and wavelength shifter, respectively. The scintillator base is linear alkyl benzene (LAB). Eight hundred liters of Gd-LS has been synthesized and tested in a prototype detector. Results show that the Gd-LS has high quality and is suitable for underground experiments in large quantity. Large scale production facility has been built. A full batch production of 4 t Gd-LS has been produced and monitored for several months. The production of 180 t Gd-LS will be carried out in the near future. [ABSTRACT FROM AUTHOR]

Simple theory predicts that the statistical noise variance in PET can be reduced by an order of magnitude by using time-of-flight (TOF) information. This reduction can be obtained by improving the coincidence timing resolution, and so would be achievable in clinical, whole body studies using with PET systems that differ little from existing cameras. The potential impact of this development is large, especially for oncology studies in large patients, where it is sorely needed. TOF PET was extensively studied in the 1980’s but died away in the 1990’s, as it was impossible to reliably achieve sufficient timing resolution without sacrificing other important PET performance aspects, such as spatial resolution and efficiency. Recent advances in technology (scintillators, photodetectors, and high speed electronics) have renewed interest in TOF PET, which is experiencing a rebirth. However, there is still much to be done, both in instrumentation development and evaluating the true benefits of TOF in modern clinical PET. This paper looks at what has been accomplished and what needs to be done before time-of-flight PET can reach its full potential. [ABSTRACT FROM AUTHOR]

Rare earth Cerium doped Lutetium Aluminum Garnet (Ce:LuAG) ceramics are widely used as phosphor material in medical imaging and high-energy physics. Due to its technological importance, an attempt has been made to fabricate Ce:LuAG ceramics by using spark plasma sintering (SPS) technique. XRD patterns of SPS sintered Ce:LuAG ceramics reveals a mixed LuAG and CeO2 (antisite defect) phases. The microstructures of SPS sintered Ce:LuAG ceramics shows limited densification, inappropriate compaction of particles and existence of residual pores, voids between the grain boundaries affects the transparency of Ce:LuAG ceramics. Relative density and hardness of post sintered Ce:LuAG ceramic is also determined. The effect of Ce3+ doping concentration and sintering temperature on optical luminescence behavior of Ce:LuAG ceramic is presented. [ABSTRACT FROM AUTHOR]

In order to increase the range of targets for rare events detection at low temperature such as dark matter or neutrinoless double beta decay events, we have developed an optical cryostat to study the scintillation of crystals down to 2.8 K under γ particles, thanks to its compact optical geometry. Some scintillation properties of BGO (Bi4Ge3O12) at low temperature obtained with this setup will be shown here. [ABSTRACT FROM AUTHOR]

Device for detection of explosives, radioactive and heavily shielded nuclear materials in luggage and cargo containers based on Nanosecond Neutron Analysis / Associated Particles Technique (NNA/APT) is under construction. Detection module consists of a small neutron generator with built-in positionsensitive detector of associated alpha-particles, and several scintillator-based gamma-ray detectors. Explosives and other hazardous chemicals are detected by analyzing secondary high-energy gamma-rays from reactions of fast neutrons with materials inside a container. The same gamma-ray detectors are used to detect unshielded radioactive and nuclear materials. An array of several neutron detectors is used to detect fast neutrons from induced fission of nuclear materials. Coincidence and timing analysis allows one to discriminate between fission neutrons and scattered probing neutrons. Mathematical modeling by MCNP5 and MCNP-PoliMi codes was used to estimate the sensitivity of the device and its optimal configuration. Comparison of the features of three gamma detector types - based on BGO, NaI and LaBr3 crystals is presented. [ABSTRACT FROM AUTHOR]

The Fermi Gamma Ray Burst Monitor (GBM) enhances the science return from the Fermi mission by providing observations of GRBs in the energy range 8 keV to 40 MeV, thereby extending GRB spectra three decades below the Large Area Telescope (LAT) threshold of ∼20 MeV. GBM employs twelve sodium iodide scintillation detectors and two bismuth germinate scintillation detectors to observe the full unocculted sky. The flight software localizes GRBs and can generate a request to autonomously repoint the spacecraft to place a burst within the LAT field of view. GBM has a trigger threshold of 0.74 photons-cm-2-s-1 and triggers on ∼260 bursts per year, as well as a variety of other gamma-ray transients. [ABSTRACT FROM AUTHOR]

We report the activities of the Pohang Neutron Facility which consists of an electron linear accelerator, a water-cooled Ta target, and a 12-m time-of-flight path. It has been equipped with a four-position sample changer controlled remotely by a CAMAC data acquisition system, which allows simultaneous accumulation of the neutron time of flight spectra from 4 different detectors. It can be possible to measure the neutron total cross-sections in the neutron energy range from 0.1 eV to few hundreds eV by using the neutron time-of-flight method. A 6LiZnS(Ag) glass scintillator was used as a neutron detector. The neutron flight path from the water-cooled Ta target to the neutron detector was 12.1 m. The background level was determined by using notch-filters of Co, In, Ta, and Cd sheets. In order to reduce the gamma rays from bremsstrahlung and those from neutron capture, we employed a neutron-gamma separation system based on their different pulse shapes. The present measurements of several samples (Ta, Mo) are in general agreement with the evaluated data in ENDF/B-VI. We measured the thermal neutron capture cross-sections and the resonance integrals of the 186W(n,γ)187W reaction and the 98Mo(n,γ)99Mo reaction by the activation method using the 197Au(n,γ)198Au monitor reaction as a single comparator. We also report the isomeric yield ratios for the 44 m, gSc isomeric pairs produced from four different photonuclear reactions 45Sc(γ,n)44m,gSc, natTi(γ,xn1p)44m,gSc, natFe(γ,xn5p)52m,gMn, and 103Rh(γ,4n)99m,gRh by using the activation method. [ABSTRACT FROM AUTHOR]

The THC14 PET Cyclotron produced by THALES specifies two compact cost-effective beamlines for high current PET radioisotope production. The design and development of the beamline system was reported previously in NIM B 261 (2007) pp 809–812. This paper describes the successful testing of this compact beamline at the first installation. A series of measurement data are presented starting from low current scintillator image data, higher current beam diagnostic data (baffles, collimators, targets) and finally a simultaneous dual beam run on Faraday Cups. The beamline system has proven to be a flexible and valuable tool for optimizing high current beam intensity distribution on target in a well-instrumented manner. This ability to tailor the beam characteristics for the target is particularly important as high power targets are developed which can handle very high beam currents. [ABSTRACT FROM AUTHOR]

The Versatile Array of Neutron Detectors at Low Energy (VANDLE) is a new array of plastic scintillator bars under development for measurements at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. The array is highly modular allowing the configuration of the individual elements to be optimized for particular experimental requirements, such as (d,n) and beta-delayed neutron-decay measurements with neutron-rich rare isotope beams. [ABSTRACT FROM AUTHOR]

BrilLanCe 380™ (LaBr3:Ce) crystal scintillators available from Saint-Gobain Crystals have achieved 2.6% FWHM for 662 keV photons. This is accomplished with PMT light sensors. Attempts to have similarly good results with PIN photo-diodes and APDs have not been successful. PIN photodiodes do not have any gain and the signal to noise ratio is poor at room temperature. Similarly, even though APDs have sufficient gain, they have poor signal to noise at room temperature. Recently there have been improvements in APDs decreasing the internal noise and increasing their sensitivity, making them an excellent light sensor. With the improved APD, it is now possible to achieve performance with a solid state light sensor comparable to that of PMTs. We have measured 2.8% for 662 keV gamma rays at room temperature using an APD for a light sensor on a 20 mm long crystal of 1.6 cc volume. APDs have advantages of compactness, inherent ruggedness and minimal sensitivity to magnetic fields. Such a device is very practical for hand held and portable field measurement applications. (Performance reported in SGC literature.) [ABSTRACT FROM AUTHOR]

The efficiency of the Modular Neutron Array (MoNA), located at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University, was measured and compared to simulations. The Coulomb dissociation of a 90 MeV/u beam of 11Be in a gold target was used to produce neutrons. The expected neutron production rate was calculated using the virtual photon method. The measured efficiency agrees with the efficiency calculated with GEANT simulations. The current configuration of MoNA has a 73% intrinsic detection efficiency for 90 MeV neutrons. [ABSTRACT FROM AUTHOR]

We recorded 600,000 (EASs) from Dec. 2006 to Oct. 2007 with a small array of water Cherenkov detectors. We found zenith and azimuth distributions of these events that confirm previous distributions from array of scintillator detectors. The study on EGRET sources are under consideration, besides, we have improved the size of our detectors to yield the best efficiency. The best shape for each detector will be a tank with 40 cm in diameter and 60 cm in height with a PMT in the center of lid. [ABSTRACT FROM AUTHOR]

We propose a gamma-ray burst (GRB) detector combining the silicon drift detector (SDD) array and scintillators with broadband X-ray and gamma-ray coverage (0.5–1000 keV or more), high energy resolution (2–10%) and high time resolution (∼μs) in space. To realize such compact high-performance detector without photomultiplier tubes, we constructed proto-type model using KETEK SDD with a detection area of 1 cm2 and BGO crystal. The detector shows a very good performance. Obtained FWHM energy resolution was 191 eV at 5.9 keV in the SDD, while 6.5 % at 662 keV in the BGO at -30 degrees C. Evaluation of the 7 channel SDD array and development of analog ASIC for its readout are also presented. [ABSTRACT FROM AUTHOR]

A large number of medical imaging methods, such as computed tomography, ultrasound and magnetic resonance imaging, are for quite some time digital. X-ray imaging was kept analogue until recently. Over last half a dozen years' digital radiography systems are being successfully developed. Among other advantages common to other medical imaging methods, digital X-ray imaging allow an important reduction of the X-ray doses involved in different medical diagnosis. The communication herein reports to the microtopographic inspection of laser ablation opened microcavities during development of an X-rays microdetector based on an array of wells filled with scintillator crystals. The wells were obtained by laser ablation of a 500 microns thick aluminum film. X-ray energy is converted to visible light within the crystals and then detected by a photodetector fabricated in a standard CMOS process. Aluminium thick-films were chosen as present good reflectivity in the visible range improving the amount of photons collected at each photodetector. Square wells 100 microns wide and 490 microns deep were targeted. In this communication we will report on the process of optical microtopographic characterization of the aluminium wells. This metrological process was performed in order to optimize the laser ablation system parameter in order to obtain the desired size square wells with almost vertical smooth sidewalls. [ABSTRACT FROM AUTHOR]

Several types of detectors are introduced. The principle of operation and properties of ionization and wire chambers, semiconductor detectors, scintillation detectors are reviewed. [ABSTRACT FROM AUTHOR]