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Detection of contraband depends on countermeasures, some of which involve examining cargo containers and/or their associated documents. Document screening is the least expensive, physical methods, such as gamma ray detection are more expensive, and definitive manual unpacking is most expensive. We cannot apply the full array of methods to all incoming cargoes, for budgetary reasons. We study the problem using principles of game theory, and find that best detection rates are achieved when the available budget is allocated between screening and definitive unpacking using a mixture of strategies that maximize detection rate and, further, serve to deceive opponents as to the specific tests to which contraband will be subjected. This yields increases of as much as 100% in detection, with essentially no increase in inspection cost.

Countries around the world are deploying radiation detection instrumentation to interdict the illegal shipment of radioactive material crossing international borders. These efforts include deployments in the U.S. and in a number of other countries by governments and international organizations. Most deployed radiation portal monitor systems are based on plastic scintillator for gamma-ray detection and 3He tubes for neutron detection. The approach to this homeland security application, and lessons learned, are discussed.

Inhomogeneity effect on full energy peak (FEP) efficiency in a soil sample was determined using the Monte Carlo simulation technique. The dependence of the FEP efficiency on the homogeneity in the soil was obtained for some particular photon energies ranging from 60 keV to 2 MeV and, as a result, the corresponding correction factors were obtained. This effect was more significant at lower energies and for higher inhomogeneity rates.

There is a great interest to find nuclear accidents as soon as possible and/or to carry out daily monitoring and control for nuclear facilities from a distance. In order to satisfy these requirements, a direction finding gamma-ray detector has been developed as a monitor of gamma-ray leakage from such facilities. The detector comprises three scintillators made of the same material of sodium iodine with thallium NaI(Tl). Computer simulations and laboratory experiments show the possibility of direction finding of gamma rays with reasonable accuracy.

Radionuclide emissions from nuclear contraband challenge both detection and measurement technologies to capture and record each event. The development of a sequential Bayesian processor incorporating both the physics of gamma-ray emissions and the measurement of photon energies offers a physics-based approach to attack this challenging problem. It is shown that a "physics-based" structure can be used to develop an effective detection technique, but also motivates the implementation of this approach using particle filters to enhance and extract the required information. The resulting processor is applied to feasibility data obtained from a controlled proof-of-concept experiment.

Weakly interacting massive particles (WIMPs) can be captured by heavenly objects, like the Sun. Under the process of being captured by the Sun, they will build up a population of WIMPs around it, that will eventually sink to the core of the Sun. It has been argued with simpler estimates before that this halo of WIMPs around the Sun could be a strong enough gamma ray source to be a detectable signature for WIMP dark matter. We here revisit the problem using detailed Monte Carlo simulations and detailed composition and structure information about the Sun to estimate the size of the gamma ray flux. Compared to earlier estimates, we find that the gamma ray flux from WIMP annihilations in the Sun halo would be negligible and no current or planned detectors would even be able to detect this flux., Comment: 5 pages, 1 figure. To appear in the proceedings of the Identification of Dark Matter conference (IDM 2008), Stockholm, Sweden, 18-22 August, 2008

In order to reduce the time and effort of the daily task of refilling Dewar vessels of Ge detectors with liquid nitrogen (LN(2)), we have developed an automatic LN(2) filling system equipped with a LN(2) plant. With this system, we were freed from the work of LN(2) filling. Such an LN(2) filling system is useful for moderate-scale Ge detector arrays consisting of fewer than 20 Ge detectors.

An anti-personnel landmine detection system using an inertial-electrostatic confinement fusion (IECF) neutron source and dual sensors showed excellent performance, particularly, for humanitarian landmine detection. Averaged probability of detection (POD) in this test was found to be 100% for arid soil, and 99% for other conditions including very wet soil moisture of 18.5wt%. Further improvements in reliability by making use of neutron backscattering are found to be efficient.

On July 23, 2008 GRB 080723B, a bright GRB lasting about 105 s was detected by the INTEGRAL burst alert system. This burst was also detected by the Fermi Gamma‐ray burst monitor. At this time no Fermi/GBM GCN notices were distributed to the public because Fermi was still in commissioning phase. The simultaneous detection of a bright GRB by both satellites gives us the opportunity to cross‐calibrate the GBM with the already well‐calibrated instruments on‐board INTEGRAL, the Spectrometer SPI and the Imager IBIS. Time‐resolved spectroscopy of this long and structured GRB is of special importance because Fermi was slewing during the GRB was still ongoing. In this paper we present a first and still preliminary analysis of the GBM spectra and compare them to those obtained by SPI for the same selection of time intervals. A more accurate cross‐calibration will be forthcoming when the improved in‐flight calibration of GBM is available and the corresponding data and responses can be reprocessed.

The AGATA Demonstrator Array is presently under installation at Laboratori Nazionali di Legnaro, Italy, where it will replace the CLARA array at the target position of the PRISMA magnetic spectrometer. In the present contribution, the details of the installation will be reviewed. Preliminary results from the first in‐beam commissioning test will be given.

The Fermi Gamma‐ray Space Telescope launched on June 11, 2008 carries two experiments onboard—the Large Area Telescope (LAT) and the Gamma‐ray Burst Monitor (GBM). The primary mission of the GBM instrument is to support the LAT in observing γ‐ray bursts (GRBs) by providing low‐energy measurements with high temporal and spectral resolution as well as rapid burst locations over a large field‐of‐view (⩾8 sr). The GBM will complement the LAT measurements by observing GRBs in the energy range 8 keV to 40 MeV, the region of the spectral turnover in most GRBs. The GBM detector signals are processed by the onboard digital processing unit (DPU). We describe some of the hardware features of the DPU and its expected limitations during intense triggers.

Since the launch of the Fermi observatory on June 11 2008, the Gamma‐ray Burst Monitor (GBM) has seen approximately 250 triggers of which about 150 were cosmic gamma‐ray bursts (GRBs). GBM operates dozens of trigger algorithms covering various energy bands and timescales and is therefore sensitive to a wide variety of phenomena, both astrophysical and not.

In the present paper, a new improved expression for gamma-ray detection efficiency of Ge(Li) detectors, epsilon-gamma-0, is given. It is represented as a continuous function of x (viz. E-gamma-1) with a maximum and decreases very rapidly to a small positive value as gamma-ray energy, E-gamma, drops to 40 keV or lower, but slowly as E-gamma rises to 1.7 MeV or higher. Since it can well represent the whole physical process of the gamma-ray detection, this expression may be one of the simplest and most precise representations, for epsilon-gamma-0 at the present time.

Recent developments in detector technologies applicable to low-energy gamma-ray detection are reviewed. Emphasis is given on the silicon technologies now being developed around particle physics laboratories. They are expected to lay basis for new generation low-energy cosmic gamma-ray detectors.

A simple setup for measuring the amount of potassium in foods is described. A 3-in. NaI detector is used to measure samples that are 3000 cm3 in size. With moderate shielding, the potassium content can be measured down to a detection limit of a few parts per 10 000.

The results of our recent investigations of lanthanide-halide- and lead-halide-based nanocrystals for applications in detection of ionizing radiation are described. We show that nanoscintillators offer significant improvements in performance coupled with great savings in cost.

The detection of special elements that can be used by terrorists in improvised chemical weapons can be performed by the spectroscopic analysis of neutron-induced gamma rays. Numerical simulations and experiments have been performed with the aim of designing a portable inspection system. Both thermal neutron analysis (TNA) and the associated particle technique (APT) have been studied within French CBNRE (chemical, biological, nuclear, radiological and explosive) R&D program. The results obtained so far show that TNA and APT can be used in complement to reach the largest possible panel of detectable elements.

AGILE is a project of the Italian Space Agency (ASI) Scientific Program dedicated to Gamma ray astrophysics.

Nuclear industry, to produce energy for example, produces also some radioactive waste. Legislation requires producers to sort their waste by activity and type of isotopes, and to package them in order to forward them to the appropriate reprocessing or storage facility. Our lab LMDE (Laboratoire de Mesures sur Dechets nucleaires et Expertise) is in charge of the characterization of the majority of waste produced by CEA-Valduc. As measurements we do have to be reliable, we also develop methods and techniques to improve them. We present to this symposium our characterization bed for germanium detectors, based on measurements and Geant4 simulations, and our study on object characterization.

CdMnTe (CMT) can be a good candidate for producing gamma-ray detectors because of its wide band-gap, high resistivity, and good electron transport properties. Further, the ability to grow CMT crystals at relatively low temperatures ensures a high yield for manufacturing detectors with good compositional uniformity and few impurities. Groups at Brookhaven National Laboratory and Institute of Physics are investigating several CMT crystals, selecting a few of them to make detectors. In this paper, we discuss our initial characterization of these crystals and describe our preliminary results with a gamma-ray source.

In this paper, we report a simple and accurate method to detect water in hollow pipes using a nanostructured thin film (NSTF). The NSTF was used as a piezoelectric transducer to mitigate health concerns generated by the current common flooded member detection technique, gamma radiography, and alleviate problems associated with using complex ceramic piezoelectric transducer arrays in flooded member detection. During testing of the NSTF's detection capabilities, discoveries were made which show the NSTF is a more viable candidate for flooded member detection than commercially available ultrasonic transducers due to the unique characteristics of the detected waveforms. Using the NSTF transducer for flooded member detection confers the accuracy and straightforward interpretation of results of radiological detection while avoiding detrimental exposure to the operator without the need of an ultrasonic multi-transducer detection system.

A 5 year task is described on the research and development of the advanced humanitarian landmine detection system by using a compact discharge-type fusion neutron source called IECF (Inertial-Electrostatic Confinement fusion) device and 3 dual sensors made of BGO and NaI. With 107 D-D neutrons/s stably produced in steady-state mode, H-2.2 MeV, N-5.3, 10.8 MeV, gamma rays from (n, gamma) reaction with nitrogen atoms in the explosives are measured for two kinds of explosives (TNT, RDX), under the conditions of three different buried depths, and soil moistures. Final detection probabilities for arid soil are found to be 100 % in the present tests, i.e., depths not exceeding 15 cm, moisture content of 18.5 % or less, and 20-minute measurements. The neutron backscattering method is found also excellent.

In this paper, implementation of the high count rate gamma-ray spectrometric system with Nal(Tl) detector is presented. The system supports count rates up to 4.2-10 pulses/s. The main focus of the paper is on implementation of algorithms for detection and correction of a pileup effect that is common at high count rates. The system is implemented on an FPGA platform and it is tested and verified using 228Th in presence of 137Cs. Experimental results show that the system is capable of reducing pileup effects and improving resolution of the energy spectrum.

Since its launch on 20 November 2004, the Swift mission is detecting ∼100 new gamma‐ray bursts (GRBs) each year, and immediately (within tens of seconds) starting simultaneous X‐ray and UV/optical observations of the afterglow. It has already collected am impressive database of bursts, including prompt emission to higher sensitivity than BATSE, uniform monitoring of afterglows, and rapid follow‐up by other observatories notified through the GCN.

Microcalorimeter detectors based on transition-edge sensors coupled to a bulk absorber are an emerging technology for hard X-ray and soft gamma-ray measurements. Monte Carlo simulations codes, like GEANT4, can be a valuable tool for evaluating detector design ideas, interpreting measured data, and predicting detector performance. We report on initial attempts to reproduce measured microcalorimeter data with GEANT4 simulations.

The paper presents the nuclear physics virtual experiments focused on presenting core aspects and features of the gamma radiation. Each experiment is programmed in full analogy with the real one performed in the real laboratory. The lasting of each step is also the same as in reality. LabVIEW software was used to carry out all the experiments, following the assumption that all the results achieved during the virtual research were not the simulated ones, but the earlier achieved ones in the real life experiments. Descriptions of the underlying physics as well as apparatus used in the virtual experiments are also presented.

The present status and understanding of the "spectral sequence" of blazars is discussed in the perspective of the upcoming GLAST launch. The vast improvement in sensitivity will allow to i) determine more objectively the "average" gamma-ray properties of classes objects ii) probe more deeply the ratio between accretion power and jet power in different systems., 3 pages, 4 figures. Proceedings of the First GLAST Symposium, to be published

Results obtained from development, testing, and evaluation of 660 keV gamma-quantum counter based on multichannel GaAs detector are presented. The counter operated in quantum count mode and counting rate up to 1000 quanta/(s-cm3) have been demonstrated for 30 cm distance between detector and 660 keV gamma-quanta source.

In recent years, heightened security concerns have prompted increased interest in radiation portal monitors, instruments capable of detecting, and in some cases identifying, gamma-ray and neutron-emitting radioactive material passing through them. Along with efficient and reliable physical detectors, such monitors need software capable of analyzing the resulting signals in order to effectively catch weak radioactive sources. The software should be able to distinguish between the sometimes subtle signals due to weak sources and the varying background. After investigating several possible source-detection algorithms, a program has been developed to locate signals from weakly radioactive sources in real time. By including corrections for background suppression due to trucks shielding the detector and changing background levels, this program is capable of detecting significantly weaker sources than current software. The limitations of this method will also be discussed.

The performance of several BrilLanCetrade LaBr3 crystals with the size of O6 times 6 mm2 up to O38 times 38 mm2 were studied coupled to the XP5212 and R6231MOD photomultipliers and in case of the small crystals, coupled also to large area avalanche photodiodes of Advanced Photonix, Inc. First, several photomultipliers of Photonis and Hamamatsu were compared in the work with LaBr3 to select the best one, not affecting energy resolution, besides the photoelectron statistics. The light output and energy resolution for 662 keV gamma rays from 137Cs source were measured for all crystals. Moreover, for some of them, the non-proportionality of the light yield and energy resolution versus gamma rays energy were measured and the intrinsic resolution of the crystals was calculated. For the smallest crystals of O6 times 6 mm2 further comparative tests with LAAPD were carried out.

The recent observations of Gamma‐ray bursts (GRBs) with Swift have provided unprecedented information about nature of GRBs. The launch of GLAST in late 2007 will unveil the final spectral regime of GRB prompt emission and afterglows. Here we briefly review various theoretical suggestions of producing high energy photons from GRB fireballs, and discuss what observatons are expected from the GLAST observatory.

Gamma‐ray pulsars are among the best targets for the Large Area Telescope (LAT) aboard the GLAST mission. The higher sensitivity, time and energy resolution of the LAT will provide data of fundamental importance to understand the physics of these fascinating objects. Powerful tools for studying the LAT capabilities for pulsar science are the simulation programs developed within the GLAST Collaboration. Thanks to these simulations it is possible to produce a detailed distribution of gamma‐ray photons in energy and phase that can be folded through the LAT Instrument Response Functions (IRFs). Here we present some of the main interesting results from the simulations developed to study the discovery potential of the LAT. In particular we will focus on the capability of the LAT to discover new radio‐loud gamma‐ray pulsars, on the discrimination between Polar Cap and Outer Gap models, and on the LAT pulsar sensitivity.

In 2006 the GLAST LAT collaboration organized a detailed simulation of 55 days of the gamma‐ray sky and particle background in orbit to test the simulation and analysis tools of the collaboration. For this simulation, designated Data Challenge 2 (DC2), empirical models for SNRs as gamma‐ray sources in the energy range of the LAT were developed, in most cases informed by X‐ray or gamma‐ray observations. The development of these models and an example of analysis of one of the simulated SNRs are described here.

We estimate the sensitivities of the AGILE and GLAST γ‐ray experiments taking into account two cases for the galactic γ‐ray diffuse background (at high galactic latitude and toward the galactic center). Then we use sensitivities to estimate microquasar observability with the two experiments, assuming the γ‐ray emission above 100 MeV of a recent microquasar model.

The Gamma‐Ray Large Area Space Telescope (GLAST), scheduled to be launched in 2007, will provide the capability to observe Gamma‐Ray Bursts (GRB) from 10 keV to more than 300 GeV. The spectral and temporal properties of GRBs above a few GeV are still almost unknown, extending these detections to higher energies with GLAST will have a large impact on our knowledge of the particle acceleration and emission processes occuring within these sources. In this work we review the requirements and the opportunities for good coordination of GLAST with ground‐based telescopes operating above a few tens of GeV, and examine the potential of such simultaneous observations in terms of expected rates of alerts.

The DAPhiNE e+e- collider, the Phi-factory currently operating at the INFN National Laboratories of Frascati (Italy), is the unconventional playground where the FINUDA Collaboration is successfully carrying on its hypernuclear study program. In view of a possible machine luminosity upgrade, it has been proposed to add to the present FINUDA spectrometer the gamma-ray detection capability. The combined exploitation of the excellent High Purity Germanium detector energy resolution and of the FINUDA performances will allow the construction of a powerful and really complete experimental setup dedicated to hypernuclear physics.

A calorimeter for the detection of gammas and light charged particles is devised within the R3B setup. It features a high resolution, large absorption efficiency and a good gamma sum energy resolution and multiplicity determination. In the article we include a brief description of the proposed calorimeter geometry, the simulation package developed for the analysis of the calorimeter response and the first crystal tests performed in our laboratory at the USC.

With more than 50 % of unidentified sources, the third EGRET catalogue reflects the complexity of source identification in the GeV domain. In that context, we developed a dedicated GLAST ScienceTool dubbed gtsrcid for the general purpose of source identification. gtsrcid has been designed in a very flexible way and allows cross correlation with any counterpart catalogue using user‐definable figures‐of‐merit. Our source identification strategy, the results for DC2 as well as possible improvements of our identification procedures are presented.

INTEGRAL detects a large number of gamma‐ray bursts outside of its field of view with the SPI ACS. Several of these bursts are also detected by IBIS. We present the results of the spectral analysis using the ISRGI, PICSIT and Compton mode data of several bursts. These bursts show very hard spectra with the high energy index reaching −2 above 1 MeV We show that there is a group of bursts with the peak energy Epeak in the MeV range. We discuss the implications of these findings for GLAST.

The giant radio galaxy M 87 was observed at GeV/TeV γ‐ray energies with the H.E.S.S. (High Energy Stereoscopic System) Cherenkov telescopes in the years 2003–2006. The observations confirm M 87 as the first extragalactic TeV γ‐ray source not of the blazar type (first indications of a signal were reported by the HEGRA collaboration earlier). The TeV γ‐ray flux as measured with H.E.S.S. is variable on time‐scales of days which strongly constrains the size of the emission region, excluding several models. The H.E.S.S. results and theoretical interpretations are presented in this paper.

The wide‐band all‐sky monitor (WAM) onboard Suzaku has the largest effective area in 300–5000 keV, and thus very powerful to constrain the E peak and high energy tail of gamma‐ray burst prompt emission. Collaboration with GLAST will give us high‐quality data of gamma‐ray prompt emissions to probe and resolve the emission mechanism and central engine of gamma‐ray bursts. Here we report initial results of the WAM and address on the collaboration with GLAST.

The Gamma‐ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT) has the opportunity to contribute to the discovery of the nature of dark matter, mainly if dark matter is composed of new Weakly Interacting Massive Particles (WIMPs). We outline the basic signatures, strategies, and experimental challenges for dark matter detection. We describe the various search techniques being developed within GLAST and how they compare with one another. We discuss the future need for precision follow‐up observations of potential GLAST dark matter sources.

The GLAST LAT instrument will monitor the GeV gamma‐ray sky with uniform exposure and high sensitivity. It will obtain a snapshot of the entire sky in a few hours and thus will allow us to observe, simultaneously, the emission of many blazars, having different level of activity (flaring, intermediate and steady states), with good timing and spectral resolution. Because of the broad‐band emission of blazars (from radio to TeV), LAT data should be combined with those obtained at all other wavelengths in order to derive most of the parameters which characterize the physical conditions of a source. Here, we present the multiwavelength campaigns planned by the LAT Science Group on Blazars and Other AGNs for 2008.

The GLAST Burst Monitor (GBM) comprises 12 NaI and 2 BGO detectors dispersed about the GLAST spacecraft. The GBM instrument simulation software must generate an accurate response function database for all detectors in their flight configuration to optimize the mission science return. Before science analysis codes use the response database, we must confirm that our simulation codes and models can reproduce laboratory observations. To validate the simulation effort, Monte Carlo results are compared to calibrated laboratory measurements collected with a variety of radiation sources.