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This issue of the IEEE Transactions on Nuclear Science (TNS) is devoted to the 21st IEEE-NPSS Real Time Conference (RT2018) on Computing Applications in Nuclear and Plasma Sciences held in Williamsburg, VA, USA, in June 2018. A total of 98 papers presented at the conference have been submitted for possible publication in TNS. The conference accepted 54 papers as oral and 149 as poster presentations in 13 tracks. [ABSTRACT FROM AUTHOR]

Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory. To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility in 2007 to support the development and deployment of enhanced in-pile sensors. This paper provides an update on this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and real-time flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted. [ABSTRACT FROM AUTHOR]

This article presents commentary on 2003 nuclear and space radiation effects conference. The 40th Annual Nuclear and Space Radiation Effects Conference was held from the July 21 to 25, 2003 at the DoubleTree Hotel, Monterey, California. The conference continued the tradition of being one of the premier international symposia on radiation effects in `electronic devices, circuits, systems, and materials. The conference was sponsored by the Institute of Electricals and Electronics Engineers Nuclear and Plasma Science Society Radiation Effects Committee.

This paper presents a digitally controlled programmable point-of-load regulator for next-generation power systems. A novel digital control scheme was designed to minimize single-event effect (SEE)-induced transient effects. By effectively programming the loop transmission, the POL can trade off transient response time with SET robustness. The IC works with 1 to 5.5 V input voltage, 1–4.5V regulated output voltage, high efficiency (peak efficiency at 94%) and power of up to 5 W. The design was fabricated in the AMI i2t100 0.7 \mum complimentary, metal-oxide semiconductor (CMOS) process and characterized with the Jet Propulsion Laboratory (JPL) pulsed laser system. [ABSTRACT FROM PUBLISHER]

DEPFET detectors are silicon (Si) active pixel sensors designed and manufactured in the Max-Planck-Institut semiconductor lab. Their high spatial resolution and high energy resolution in X-rays make them attractive for particle tracking in colliders and for X-ray astronomy. This technology is foreseen for the Wide Field Imager of the International X-ray Observatory currently in study with ESA, NASA, and JAXA. New DEPFET matrixes with 256\,\times\,256 pixels of 75-\mum pitch have been produced, mounted on ceramic boards with dedicated front-end electronics and integrated in a new setup able to acquire large-format images and spectra. Excellent homogeneity has been observed. Energy resolution as low as 127 eV FWHM at 5.9 keV has been obtained including all single events of the matrix back illuminated at -45\,^\circC and read out at a 300-frames/s rate. This paper presents experimental methods and results. [ABSTRACT FROM AUTHOR]

Frisch-ring CdZnTe detectors have demonstrated both good energy resolution, < 1% FWHM at 662 keV, and good efficiency in detecting gamma rays, highlighting the strong potential of CdZnTe materials for such applications. We are designing a hand-held gamma-ray spectrometer based on Frisch-ring detectors at Brookhaven National Laboratory. It employs an 8 × 8 CdZnTe detector array to achieve a high volume of 19.2 cm³, so greatly improving detection efficiency. By using the front-end application-specific integrated circuits (ASICs) developed at BNL, this spectrometer has a small profile and high energy-resolution. It includes a signal processing circuit, digitization and storage circuits, a high-voltage module, and a universal serial bus (USB) interface. In this paper, we detail the system's structure and report the results of our tests with it. [ABSTRACT FROM AUTHOR]

A pocket radiation detection system has been developed at the Idaho National Engineering and Environmental Laboratory for homeland security applications. It can detect both neutrons and gamma rays instantaneously. This sensor has been designed with an emphasis on compactness, recognizing the widespread need for a radiation detection instrument that could provide both neutron and gamma-ray detection in a single, portable unit. It is very small, extremely sensitive, versatile, and easy to operate. It can detect gamma rays and neutrons in a radiation field as tow as 10 μR/h above the ambient background, which makes it ideal for use in national security applications. The detection system is based on a technique of using a combination of two sensors made of lithium isotopes 6Li and 7Li. It operates on one rechargeable Li-ion battery and is small enough to be put in a pocket or clipped to a belt. In this paper, the detection technique used in developing this prototype sensor as well as its performance will be presented. [ABSTRACT FROM AUTHOR]

The facility that we developed for producing precision drift tubes of the ATLAS forward muon system is described in this paper. We have completed the production of approximately 30000 drift tubes in Seattle. The results of quality assurance for these tubes are presented. The drift tube assembly and quality assurance are two separation operations that proceed in parallel. The quality of the drift tube that we produced meets the very stringent requirements of the ATLAS experiment. The typical average production rate is 2 to 3 mm per tube and the rejection rate is less than 1.5%. [ABSTRACT FROM AUTHOR]

The transition radiation tracker (TRT) is one of the three subsystems of the inner detector of the ATLAS experiment. It combines electron identification capability with charged-particle track reconstruction. A total of 420 000 electronic channels provide continuous tracking with many projective measurements per track. This paper gives details of some features of the TRT, from performance requirements to the consequences of its operation in the LHC environment. Some technical choices and operating conditions have been recently changed, the most significant one being the active gas. Presently, a large fraction of barrel and end-cap modules have been assembled in the United States and Russia, respectively. A strict quality assessment has been implemented at the assembly sites and at CERN upon arrival of the modules. The acceptance tests include dimensional surveys, wire-tension measurements, gas-tightness tests, high-voltage training, and gas-gain uniformity measurements along each individual straw. First estimates of the module quality are presented based on the analysis of these tests. [ABSTRACT FROM AUTHOR]

The data acquisition system at the National Super- conducting Cyclotron Laboratory (NSCL), Michigan State University, East Lansing, is based on commodity PC components running an unmodified Linux kernel. A commercial PCI-VME bus bridge connects the readout processors of this system to digitization hardware. While Linux is not a real-time system, this paper shows how we have structurd the readout software to meet the requirements of the NSCL without the use of real-time or embedded components. [ABSTRACT FROM AUTHOR]

The BaBar experiment's computing resources are geographically spread out. A direct consequence of this is that a large amount of data is transferred between sites. Providing easy management and access to these data is a challenging task. To accomplish this task we are employing the storage resource broker (SRB), developed at the San Diego Super Computing Center, to manage the BaBar data files and to replicate them between Tier-A centers. The system has been tested between the computing centers l'Institut National de Physique Nucléaire et de Physique des Partictiles (CC-IN2P3), Lyon, France, and at Stanford Linear Accelerator Center (SLAC), Menlo Park, CA, and this paper discusses our experience with a view to production use. We describe how the system could be used to manage the data import/export between the computing sites and how it fits into building a BaBar data grid. We also explain how a user benefits from this system to access and obtain data in an easy and transparent fashion. [ABSTRACT FROM AUTHOR]

The development of portable nuclear instrumentation demands compact high sensitivity detectors operated at room temperature. The sensitivity of these detectors mainly depends on two parameters: absolute efficiency and energy resolution. In order to provide high efficiency, large volumes are needed. For semiconductor detectors able to operate at room temperature, the largest effective volumes with acceptable resolution are achieved with CdZnTe coplanar-grid and pixel detectors. On the other hand, new scintillation materials were recently developed with spectrometric capabilities only reachable some years ago with semiconductors. In this work we compare the performance of two state of the art detectors of different technologies with a relative large volume: a coplanar-grid CdZnTe detector with dimensions 15 mm × 15 mm × 10 mm and a LaBr3 (Ce) crystal with volume 18 mm × 18 mm × 30 mm. The CdZnTe crystal was made by Yinnel Tech (USA) and the detector was manufactured by BSI (Latvia). The LaBr3 (Ce) scintillator was grown and encapsulated by Saint-Gobain (France). The energy resolution for the CZT detector is 2.05% FWHM at 662 keV. The resolution for the scintillator at this energy was near 3 %. The total efficiency was studied in a setup with calibrated point sources. The experimental spectra were compared with Monte-Carlo simulations performed with Geant4. The implications of the results of this comparison are discussed in the context of the practical use of these units. [ABSTRACT FROM AUTHOR]

Focuses on the study of the development of an x-ray computed tomography (CT) system at Oak Ridge National Laboratory to image laboratory mice for the purpose of rapid phenotype screening and implementation. Multi-energy CT; Reconstruction algorithms; Future research; Conclusion.

Presents information regarding the trigger, readout and event gathering system which had been built for the purpose of Babar experiment at Stanford Linear Accelerated Center (SLAC), Menlo Park, California. Where the Babar detector is situated; Partitioning of the DAQ platform; What the front end electronics from the drift chamber and electromagnetic calorimeter provides.

The Focusing Optics X-ray Solar Imager (FOXSI) is a NASA sounding rocket mission which will study particle acceleration and coronal heating on the Sun through high sensitivity observations in the hard X-ray energy band (5–15 keV). Combining high-resolution focusing X-ray optics and fine-pitch imaging sensors, FOXSI will achieve superior sensitivity; two orders of magnitude better than that of the RHESSI satellite. As the focal plane detector, a Double-sided Si Strip Detector (DSSD) with a front-end ASIC (Application Specific Integrated Circuit) will fulfill the scientific requirements of spatial and energy resolution, low energy threshold and time resolution. We have designed and fabricated a DSSD with a thickness of 500 \mu\ m and a dimension of 9.6 mm \times 9.6 mm, containing 128 strips with a pitch of 75 \mu\ m, which corresponds to 8 arcsec at the focal length of 2 m. We also developed a low-noise ASIC specified to FOXSI. The detector was successfully operated in the laboratory at a temperature of -20^\circ\ C and with an applied bias voltage of 300 V. Extremely good energy resolutions of 430 eV for the p-side and 1.6 keV for the n-side at a 14 keV line were achieved for the detector. We also demonstrated fine-pitch imaging successfully by obtaining a shadow image. Hence the implementation of scientific requirements was confirmed. [ABSTRACT FROM AUTHOR]

X-ray cargo inspection systems for the detection and verification of threats and contraband must address competing performance requirements. In addition to high x-ray energy, high x-ray intensity is needed to penetrate dense cargo, while low intensity is desirable to minimize the radiation footprint, i.e. the size of the controlled area, required shielding and the dose to personnel. We report here on a collaborative effort between HESCO/PTSE Inc., Schonberg Research Corporation and Rapiscan Laboratories, Inc. to design an Intensity-Modulated Advanced X-ray Source (IMAXS) that allows such cargo inspection systems to achieve up to two inches greater penetration capability, while on average retaining the same radiation footprint as present fixed-intensity sources. Alternatively, the new design can be used to obtain the same penetration capability as with conventional sources, but reducing the average radiation footprint by about a factor of three. The key idea is to anticipate the needed intensity for each x-ray pulse by evaluating signal strength in the cargo inspection system detector array for the previous pulse. Requirements there- fore include an x-ray source capable of changing intensity from one pulse to the next by electronic signal, as well as electronics inside the cargo inspection system detector array determining the required source intensity for the next pulse. The feasibility of pulse-to-pulse intensity modulation of both S-band (2998 MHz) and X-band (9303 MHz) linac sources has been demonstrated. [ABSTRACT FROM AUTHOR]

Detection and interdiction of nuclear materials in all forms of transport is one of the most critical security issues facing the United States and the rest of the civilized world. Naturally emitted gamma rays by these materials, while abundant and detectable when unshielded, are low in energy and readily shielded. X-ray radiography is useful in detecting the possible presence of shielding material. Positive detection of concealed nuclear materials requires methods which unequivocally detect specific attributes of the materials. These methods typically involve active interrogation by penetrating radiation of neutrons, photons or other particles. Fortunately, nuclear materials, probed by various types of radiation, yield very unique and often strong signatures. Paramount among them are the detectable fission signatures, namely prompt neutrons and gamma rays, and delayed neutrons gamma rays. Other useful signatures are the nuclear states excited by neutrons, via inelastic scattering, or photons, via nuclear resonance fluorescence and absorption. The signatures are very different in magnitude, level of specificity, ease of excitation and detection, signal to background ratios, etc. For example, delayed neutrons are very unique to the fission process, but are scarce, have low energy, and hence are easily absorbed. Delayed gamma rays are more abundant but "featureless," and have a higher background from natural sources and more importantly, from activation due to the interrogation sources. The prompt fission signatures need to be measured in the presence of the much higher levels of probing radiation. This requires taking special measures to look for the signatures, sometimes leading to a significant sensitivity loss or a complete inability to detect them. Characteristic gamma rays induced in nuclear materials reflecting their nuclear structure, while rather unique, require very high intensity of interrogation radiation and very high resolution in energy and/or time. The trade off of signatures, their means of stimulation, and methods of detection, will be reviewed. [ABSTRACT FROM AUTHOR]

The radiation effects community has developed a number of hardness assurance test guidelines to assess and assure the radiation hardness of integrated circuits for use in space and/or high-energy particle accelerator applications. These include test guidelines for total dose hardness assurance qualification and single event effects (SEE) qualification. In this work, issues associated with these hardness assurance test guidelines are discussed. For total dose qualification, the main test methodologies used in the U.S. and Europe are reviewed and differences between the guidelines are discussed. In addition, some key issues that must be considered when performing total dose hardness assurance testing are addressed. Following these discussions we review some emerging issues relevant to SEE device qualification that are not covered in present SEE test guidelines. The hardness assurance implications of these issues are addressed. [ABSTRACT FROM AUTHOR]

We describe the design and performance of a position sensitive scintillator detector developed for neutron measurements. Several of these detectors are to be used in the assembly of the Fast Neutron Imaging Telescope (FNIT), an instrument with imaging and energy measurement capabilities, sensitive to neutrons in the 2–20 MeV energy range. FNIT was initially conceived to study solar neutrons as a candidate instrument for the Inner Heliospheric Sentinels (IHS) program under formulation at NASA. It is now being adapted to locate Special Nuclear Material (SNM) for homeland security purposes by detecting fission neutrons and reconstructing the image of their source. The detection principle is based on multiple elastic neutron-proton scatterings in organic scintillator. The detector presented here utilizes wavelength-shifting (WLS) fibers, grooved into the plastic scintillator and read out by multianode photomultiplier tubes (MAPMTs) to determine scattering locations. By also measuring the recoil proton and scattered neutron's energies, the direction and energy spectrum of incident neutrons can be determined and discrete sources identified. [ABSTRACT FROM AUTHOR]

The current interest in returning to the Moon and Mars by 2030 makes cost effective and low mass health monitoring sensors essential for spacecraft development. In space, there are many surface measurements that are required to monitor the condition of the spacecraft including: surface temperature, radiation dose, and impact. Through the use of phosphors, these conditions can be monitored. Practical space-based phosphor sensors will depend heavily upon research investigating the resistance of phosphors to ionizing radiation and the ability to anneal or self-heal from damage caused by ionizing radiation. The cathodoluminescence (CL) testing was performed using the low energy electron system located at the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama. For the materials tested, several interesting results were observed. For most materials, increases in both beam energy and current density improved the CL fluorescence yield. It was also noted that YAG:Nd,Ce has the greatest near infrared intensity for any of the tested materials. The evaluation of dopant concentration in YPO4:Nd showed minimal differences in spectral shape and intensity. While the total electron dose was small, the intention was to maximize the number of irradiated materials. [ABSTRACT FROM AUTHOR]

We report on irradiation induced SEU by high-energy protons and neutrons. The experiments were performed at The (odor) Svedberg Laboratory in Uppsala, Sweden, and at the Weapons Neutron Research (WNR) facility, Los Alamos, USA. A wide range of SRAMs were used to study the differences between proton and neutron induced SEUs at different energies. [ABSTRACT FROM AUTHOR]

We evaluated an analytic attenuation correction method for the National Institutes of Health (NIH) Advanced Technology Laboratory Animal Scanner (ATLAS) small animal positron emission tomography (PET) scanner. This method is based on the body outline of emission images and an average empirical μ (linear attenuation coefficient) value. We evaluated this method using a computed tomography (CT)-based attenuation correction (ACs) as the "gold standard." A specially fabricated attenuation calibration phantom with cylindrical inserts that mimic different body tissues was used to derive the relationship to convert CT values to μ for PET. The methods were applied to three test data sets: 1) a uniform cylinder phantom, 2) the attenuation calibration phantom, and 3) a mouse injected with [18F]FDG. CT-based correction achieved activity restorations expected for all three data sets. The analytic method showed similar correction factors for the cylinder phantom and the mouse for which the attenuation medium volume matches the detectable emission source distribution. The correction factor for the attenuation calibration phantom was smaller because the emission image outline underestimated the attenuation medium volume. [ABSTRACT FROM AUTHOR]

The Washington area large-scale time coincidence array (WALTA) is placing particle detector arrays in secondary schools in the Seattle area to build up a large-scale ultrahigh-energy cosmic ray detector network, one of several such projects around the world. Scintillation counters salvaged from the CASA experiment in cooperation with the CROP group at the University of Nebraska at Lincoln are refurbished by teachers and students, tested, calibrated, and installed in fourfold arrays at high school sites. To identify time coincidences, a GPS time synchronization system is employed. Data are acquired using a custom low-cost data acquisition card. Here we will describe the logistics of WALTA and show samples of data taken with a prototype array at the University of Washington. [ABSTRACT FROM AUTHOR]

Pacific Northwest National Laboratory (PNNL), Richland, WA, is currently developing multicoincidence systems to perform trace radionuclide analysis at or near the sample collection point for applications that include emergency response, nuclear forensics, and environmental monitoring. Quantifying radionuclide concentrations with these systems requires a library of accurate emission intensities for each detected signature, for all candidate radionuclides. While such data are readily available for single gamma-ray emissions, no signature library has been found for coincident emissions such as β - γ, γ - γ, or β - γ - γ. To meet this need, a Coincidence Lookup Library (CLL) is being developed to calculate the emission intensities of coincident signatures from a user-specified radionuclide, or conversely, to determine the radionuclides that may be responsible for a specific detected coincident signature. The algorithms used to generate absolute emission intensities and various user interfaces for the developmental CLL are described. [ABSTRACT FROM AUTHOR]

The Cosmic Ray Observatory Project (CROP) at University of Nebraska/Lincoln and the Washington Area Large-scale Time coincidence Array (WALTA) at University of Washington/Seattle are among several outreach projects siting cosmic-ray detectors at local high schools in cities around North America, to study the origins and interactions of high-energy cosmic rays. In a collaboration between QuarkNet, the outreach program based at Fermilab, CROP, and WALTA, a low-cost data acquisition electronics card has been developed to collect and synchronize the data from each detector site. The cost per card is under US$500 for parts (for 15 boards), functionally replacing much more expensive electronics crates and modules at each high school site. The card has four analog discriminator inputs for photomultiplier tube signals, a four-channel time-to-digital converter (TDC) for local coincidence and time-over-threshold measurements with ∼ 1 ns resolution, programmable trigger logic via a CPLD and microcontroller, and a built-in low-cost GPS receiver/antenna module (via external cable) to provide event trigger time stamps with 50 ns accuracy. Temperature sensors and a barometer are also integrated to record environmental data along with the counter data. The card connects to any PC or laptop via a standard RS-232 serial port for data output and control. The microcontroller and CPLD are field programmable and thus make the card functionality flexible and easy to upgrade. [ABSTRACT FROM AUTHOR]

Presents the result of a collaboration between Brookhaven National Laboratory and eV Products which developed a high performance readout application specific integrated circuit (ASIC). Structure of ASIC; Preamplifier and continuous reset system; Prototypes of ASIC; Experimental results; Conclusions.

Explores single-pixel cadmium zinc telluride (CZT) and phospher screen detector, two high-resolution x-ray computer tomography system for mouse imaging developed in the Oak Ridge National Laboratory Mammalian Genetics Research Facility in Tennessee. System description; Capabilities of CZT detector and phospher screen detector; Image comparison.