Research at the RSEC

Testing Fast Neutron-Induced Soft Errors in Semiconductor Memories

K. Ünlü,^{1, 2} N. Vijaykrishnan,³ M. J. Irwin,³ B. Heidrich,¹ C. Celik,^{1, 2}K. Ramakrishnan,³

Service Provided:  Fast Neutron Irradiator

Sponsors:  National Science Foundation, U.S. Department of Energy, Pennsylvania State University Radiation Science and Engineering Center, Pennsylvania State University Department of Computer Science and Engineering

Soft errors are transient circuit errors caused due to excess charge carriers induced primarily by external radiation. Radiation directly or indirectly induces localized ionization that can flip the internal values of the memory cells.   Read more...

Testing Thermal Neutron-Induced Soft Errors in Semiconductor Materials

N. Vijaykrishnan,¹ M. J. Irwin,¹ K. Ünlü,^{2, 3} K. Ramakrishnan,¹ S. M. Centiner,^{2, 3} C. Celik,^{2, 3}

Service Provided:  Neutron Beam Lab

Sponsors:  U.S. Department of Energy Innovations in Nuclear Infrastructure and Education (INIE) grant, Pennsylvania State University Radiation Science and Engineering Center, Pennsylvania State University Department of Computer Science and Engineering

Soft errors are transient circuit errors caused due to excess charge carriers induced primarily by external radiation. Radiation directly or indirectly induces localized ionization that can flip the internal values of the memory cells.   Read more...

Soft Error Modeling and Analysis of the Neutron Intercepting Silicon Chip

C. Çelik,^{1, 2} K. Ünlü,^{1, 2} N. Vijaykrishnan, ³ M. J. Irwin,³

Service Provided:  Neutron Beam Lab

Sponsors:  National Science Foundation, U. S. Department of Energy, INIE Mini Grant, the Penn State Radiation Science and Engineering Center, and the Penn State Department of Computer Science and Engineering

Advances in microelectronic technologies result in semiconductor memories with sub-micrometer transistor dimensions. While the decrease in the dimensions satisfy both the producers and consumers requirements, it also lead to a higher susceptibility of integrated circuit designs to temperature, magnetic interference, power supply and environmental noise, and radiation.  Read more...

Cosmic Ray Background Effects on the Neutron Intercepting Silicon Chip

C. Çelik,^{1, 2} K. Ünlü,^{1, 2} N. Vijaykrishnan, ³ M. J. Irwin,³

Service Provided:  Neutron Beam Lab

Sponsors:  National Science Foundation, U. S. Department of Energy, INIE Mini Grant, the Penn State Radiation Science and Engineering Center, and the Penn State Department of Computer Science and Engineering

Cosmic rays primarily consist of galactic and solar particles, and continuously penetrate the earth’s atmosphere. Solar particles originate from the sun with energies of up to 1 GeV, with particle fluxes dependant on the 11-­-year period solar cycle. However, due to interactions with the atmosphere, almost all of the solar particles are absorbed atmospherically, creating no particles at sea level. On the other hand, galactic particles, mainly protons, have enormous energies (up to 10⁸ GeV) and create cascades of particles that can also generate secondary cascades of particles [1, 2].   Read more...

Neutron Activation Analysis of Absolutely-Dated Tree Rings

D. K. Schwarz,^{1, 2} N. O. Centiner,^{1, 2} D. Sahin,^{1, 2} T.H. Daubenspeck,¹ K. Ünlü^{1, 2}

Service Provided:  Neutron Activation Analysis, Radionuclear Applications Laboratory

Sponsors:  National Science Foundation, Department of Energy Nuclear Engineering Education Research grant, Cornell University's Malcolm and Carolyn Wiener Laboratory for Aegean and Near-Eastern Dendrochronology, and the Pennsylvania State University Radiation Science and Engineering Center

Neutron Activation Analysis (NAA) is the preferred analysis method for studying the composition of tree-rings. It was hypothesized when the project began that gold would be well suited as an environmental marker in tree-rings.   Read more...

Dendrochemical Findings for Pinus Nigra Trees Grown in the  Mediterranean Region

Dagistan Sahin,¹ K. Ünlü,¹ Peter I. Kuniholm,^{2, 3} Charlotte Pearson,²

Service Provided:  Dry Irradiation Tube, Radionuclide Analysis Laboratory

Sponsors:  The Penn State Radiation Science and Engineering Center, Cornell University Malcolm and Carolyn Wiener Laboratory for Aegean and Near Eastern Dendrochronology

The aim of this study was to analyze elemental constituents of tree-­-ring samples from Pinus nigra trees grown in the Mediterranean region. It has been previously shown that elemental concentrations in tree-rings may be correlated with significant chemical changes in the soil environment, such as fallout from volcanic ash and acid rain.   Read more...

Characterization of Italian Tile Samples Using Comparative Neutron  Activation Analysis

C. B. Durrant,^{1, 2} A. M. Johnsen,² K. Ünlü,^{1, 2}

Service Provided:  Neutron Activation Analysis, Radionuclear Application Laboratory

Sponsors:  Pennsylvania State University Radiation Science and Engineering Center, Department of Homeland Security Nuclear Foresnsics Graduate Fellowship

Comparative neutron activation analysis (CNAA) is a technique used to determine trace element compositions of unknown samples by comparing them with samples containing known trace element concentrations. Both samples are activated with thermal neutrons and the resulting delayed gamma-rays are measured.   Read more...

Installation and Testing of a Compton Suppression System

K. Ünlü,^{1, 2} J. S. Brenizer,² N. O. Cetiner,^{1, 2} D. K. H. Schwarz,^{1, 2}

Service Provided:  Radionuclear Application Laboratory

Sponsors:  U.S. Department of Energy Innovations in Nuclear Infrastructure and Education (INIE) and Nuclear Engineering Education and Research (NEER) grants, Pennsylvania State University Radiation Science and Engineering Center

The three major interaction mechanisms of gamma-­- rays with matter are photo-­-electric absorption, Compton scattering, and pair production. In all of these interactions, the gamma-­-ray photon energy is partially or completely transferred to an electron.   Read more...

Compton Suppressed LaBr3 Detection System for use in Nondestructive  Spent Fuel Assay

S. Bender,^{1, 2} B. Heidrich,^{1, 3} K. Ünlü,¹

Service Provided:  Penn State Breazeale Reactor, Neutron Beam Lab, Neutron Activation Analysis

Sponsors:  U.S. Department of Energy, U.S. Department of Homeland Security, U.S. Department of Defense, the Penn State Radiation Science and Engineering Center

Nuclear material accountancy is of continuous concern for the regulatory, safeguards, and verification communities. In particular, spent nuclear fuel reprocessing facilities pose one of the most difficult accountancy challenges: monitoring highly radioactive, fluid sample streams in near real-time. Current accountancy methods for nuclear fuel reprocessing facilities are resource intensive and time-consuming. The adaptation of passive gamma-ray detection coupled with multivariate analysis techniques could reduce the personnel requirements and sample processing times.   Read more...

Neutronic Design and Analyses of A New Core-Moderator Assembly and  Neutron Beam Ports for The Penn State Breazeale Reactor

D. Ucar,¹ K. Ünlü,^{1, 2} B. J. Heidrich,¹K.N. Ivanov,²M.N. Avramova,²

Service Provided:  Penn State Breazeale Reactor, Neutron Beam Laboratory

Sponsors:  The Pennsylvania State University Radiation Science and Engineering Center

The Penn State Breazeale Reactor (PSBR), as a part of Radiation Science and Engineering Center (RSEC), was built in 1955 as a research and education hub. It is currently the longest operating research reactor in the United States. The initial reactor design used plate-­-type materials testing reactor (MTR) fuel elements with a 61-­-cm active fuel length and up to 93% uranium enrichment. Seven beam ports were built into the facility design for analyzing the nuclear properties of materials, determining reactor dynamics, and examining the effects of radiation on materials.   Read more...

Neutronic Analysis of the Penn State Breazeale Nuclear Reactor Using the  MURE Computer Code

Dagistan Sahin,¹ K. Ünlü,^{1, 2} Kostadin Ivanov,²

Service Provided:  Breazeale Nuclear Reactor

Sponsors:  The Penn State Radiation Science and Engineering Center

The Pennsylvania State University (PSU) Radiation Science and Engineering Center (RSEC) hosts the Penn State Breazeale Nuclear Reactor (PSBR), a TRIGA Mark III-­-type 1 MW nuclear reactor. The PSBR has a well-­- documented and analyzed operation history starting from 1955.   Read more...

Thermal-Hydraulic Analysis of A New Core-Moderator Assembly Design  for the Penn State Breazeale Reactor Using the ANSYS Fluent Code

D. Ucar,¹ K. Ünlü,^{1, 2} B. J. Heidrich,¹

Service Provided:  Penn State Breazeale Reactor

Sponsors:  The Penn State Radiation Science and Engineering Center

The Penn State Breazeale Reactor (PSBR), a TRIGA Mark-­-III design, is an open-­-pool type reactor that is cooled by the natural circulation of the demineralized and filtered water. The reactor core operates at a depth of ~5.5 m (18 ft) in the reactor pool, which has dimensions of 9.14 m in length, 4.27 m in width and 7.21 m in depth, and at a pressure of ~1.5 atm. The driving force for the natural circulation of the water is the heat generation within the fuel rods. The PSBR   Read more...

Research Reactor Production and Purification of ⁶⁴Cu and ⁶⁷Cu Using  Enriched Zinc Target Materials

A. M. Johnsen,¹ B. J. Heidrich,¹ C. B. Durrant,^{1, 2} A. J. Bascom,^{1, 2} K. Ünlü,^{1, 2}

Service Provided:  Penn State Breazeale Reactor, Radiochemistry Research Laboratory

Sponsors:  U.S. Department of Energy Office of Science (Nuclear Physics)

⁶⁴Cu and ⁶⁷Cu are short-lived, radioactive theranostic medical isotopes in high demand for use as therapeutic treatment agents for multiple types of cancer and in medical diagnostics. However, they have had a limited and inconsistent supply for several decades [1], [2]. To aid in their availability, we conducted preliminary development work for their production in a research reactor and their purification in our unique radioactive handling facilities, while also educating and training students in medical isotope production methods.   Read more...

University Research Reactor Production of ⁶⁷Cu via Long-Term  Irradiation

B. J. Heidrich, A. M. Johnsen, A. J. Bascom,J. Krizmanich,M. D. Wargon,

Service Provided:  Penn State Breazeale Reactor, Radiochemistry Research Laboratory, Computational Laboratory

Sponsors:  U.S. Department of Energy Office of Science, The Penn State Radiation Science and Engineering Center

Medical isotopes are particularly valuable for their widespread use as diagnostic tools, therapeutic agents for disease treatment, and as aids in pharmaceutical research and development [1]. Inconsistent medical isotope supplies limit our ability to develop and implement improved diagnostic and therapeutic procedures [2], and limited domestic isotope production leaves only a small number of scientists and engineers with the expertise to manufacture and purify these elements.   Read more...

Evaluating HDEHP and HEH[EHP] Ligands for use in Polymer Ligand Films  (PLFs) for Plutonium Extraction

Jung H. Rim,^{1, 2} Dominic S. Peterson,³ Claudine E. Armenta,³ Edward R. Gonzales,³ K. Ünlü,¹

Service Provided:  Neutron Beam Lab

Sponsors:  U.S. Department of Homeland Security, U.S. Department of Defense, U.S. Department of Energy, and the Penn State Radiation Science and Engineering Center

There is great interest in developing new, field deployable alpha analysis techniques for nuclear forensics applications [1–4]. The current techniques are well established for radionuclide measurement; however, they are slow and labor intensive, requiring extensive radiochemical separations and purification prior to analysis.   Read more...

Fission Track Analysis of Electrodeposited Uranium Alpha Sources

Jung H. Rim,^{1, 2} K. Ünlü,¹

Service Provided:  Neutron Beam Laboratory

Sponsors:  U.S. Department of Homeland Security, U.S. Department of Defense, U.S. Department of Energy, and the Penn State Radiation Science and Engineering Center

Fission track analysis (FTA) is a highly sensitive and reliable analytical technique for mapping the spatial distribution of trace levels of fissile isotopes. The FTA technique uses the neutron induced fission reaction for the detection of the isotopes and follows a three step process that includes: sample preparation, irradiation, and etching.   Read more...

Liquid Water Storage and Removal from Polymer Electrolyte Fuel Cells

M. M. Mench,¹ J. Brenizer,¹ K. Ünlü,^{1, 2} K. Heller,¹ A. Turhan,¹ L. Shi,¹ J. J. Kowal,¹ C. Chacko,¹

Service Provided:  Neutron Beam Laboratory

Sponsors:  Automotive manufacturers (one domestic and one foreign), U.S. Department of Energy Nuclear Engineering Education Research (NEER) and Innovations in Nuclear Education and Infrastructure (INIE) grants

The residual water content stored in fuel cell media under steady or time-varying operation is of great interest, because it can play a critical role in the operating performance, pressure loss, degradation via ionic contaminants or mechanical damage, and time to start and degradation from a frozen condition.   Read more...

Residual Water Distribution and Removal from Polymer Electrolyte Fuel  Cells

M. M. Mench,¹ J. Brenizer,¹ K. Ünlü,^{1, 2} K. Heller,¹ A. Turhan,¹ J. J. Kowal,¹

Service Provided:  Neutron Beam Laboratory

Sponsors:  Automotive Manufacturer

Polymer electrolyte fuel cells (PEFCs) are a promising energy source due to their high efficiency and low emissions. However, there are still many components and processes associated with PEFCs that need to be optimized. One major concern with PEFCs is the water.   Read more...

Neutron Imaging System Improvements

J. Brenizer,¹ M. M. Mench,¹ K. Ünlü,^{1, 2} K. Heller,^{1, 2} A. Turhan,^{1, 2} L Shi,^{1, 2} J. J. Kowal,^{1, 2}

Service Provided:  Neutron Beam Laboratory

Sponsors:  U.S. Department of Energy Innovations in Nuclear Infrastructure and Education (INIE) grant, Pennsylvania State University Radiation Science and Engineering Center, Pennsylvania State University Department of Mechanical and Nuclear Engineering, a private automotive manufacturer

The growing demand for dynamic neutron imaging (radioscopy), especially for fuel cell research, has stretched our existing neutron imaging capabilities. These included developing a more efficient means of data acquisition and storage, better post processing techniques, and a more accurate quantification of water present in the radioscopic images.   Read more...

Effect of Irradiation on Nonlinear Optical Recirculation Cavity  Performance

M. Saitta,¹ R. Tikhoplav,² I. Jovanovic,¹

Service Provided:  Breazeale Nuclear Reactor

Sponsors:  U.S. Department of Energy and RadiaBeam Technologies

In applications such as the production of hydrogen ions for accelerators in spallation neutron sources, including the Oak Ridge National Laboratory’s Spallation Neutron Source (SNS), charge stripping of hydrogen ions using high-­-power lasers represents an attractive technical approach.   Read more...

Development of a Time of Flight Spectrometer for Application to Neutron  Depth Profiling

S. M. Centiner,^{1, 2} K. Ünlü,^{1, 2} R. G. Downing,³ M. Gordon,⁴

Service Provided:  Neutron Beam Laboratory

Sponsors:  U.S. Department of Energy Nuclear Engineering Education Research (NEER) and Innovations in Nuclear Education and Infrastructure (INIE) grants, Pennsylvania State University Radiation Science and Engineering Center

Neutron depth profiling (NDP) is a near-­-surface analysis technique to measure the spatial distribution of certain light isotopes of technological importance in substrates with low neutron affinity. Ziegler [1,2] first reported the use of neutron depth profiling as a nuclear reaction analysis (NRA) technique to obtain boron profiles in semiconductors. Biersack et al [3] later thoroughly investigated and improved the technique to almost present capabilities.   Read more...

Thermal Hydraulic Analysis of Neutron Cooling Systems

S. Yavuzkurt,¹ K. Ünlü,^{1, 2} H. Malaku,¹ C. Celik,^{1, 2}

Service Provided:  Neutron Beam Laboratory

Sponsors:  U.S. Department of Energy Innovations in Nuclear Infrastructure and Education (INIE) grant, Pennsylvania State University Radiation Science and Engineering Center, Pennsylvania State University Department of Mechanical and Nuclear Engineering

Cold neutrons, which are low energy neutrons useful for investigating basic material and biological properties, can be obtained in several ways. Only two cold neutron beam facilities have been developed at U.S. university research reactors, namely at Cornell University and the University of Texas at Austin. Both facilities used a mesitylene moderator.   Read more...

Neutron Energy Spectra Characterization Using a ³H Neutron  Spectromoter

C. Trivelpiece,¹ J. S. Brenizer,¹ K. Ünlü,^{1, 2}

Service Provided:  Neutron Beam Laboratory, Radiological Hot Cell Laboratory, Sealed Neutron Sources

Sponsors:  U.S. Department of Energy Innovations in Nuclear Education and Infrastructure (INIE) grant

Neutron beams are used in a variety of experimental methods at research reactors all across the United States. Such applications include: neutron imaging and neutron tomography, neutron depth profiling, neutron diffraction, neutron scattering etc.   Read more...

Impact of Thermal Neutrons on Boro-carbon-oxy-nitride (BCON)

Ganesh R. Bhimanapati,¹ Maxwell Wetherington,² Joshua A. Robinson,²

Service Provided: Breazeale Nuclear Reactor  

Sponsors:  Defense Threat Reduction Agency

Thermal neutrons have an average kinetic energy corresponding to the average energy of the particles of the ambient materials [1]. These neutrons are relatively slow and possess a relatively lower energy. Hence they have a large area of cross section (Figure 1). The energy of a thermal neutron is about 0.025 eV. For thermal neutrons, gadolinium, boron, lithium, and hydrogen have a high neutron capture cross section. In this work, we have used boron nitride as our boron source because of its compatibility with graphene oxide (GO) to form a heterogeneous composite. Also, boron is within the detection limits of the X-­-ray photoelectron spectroscopy (XPS) technique used for the analysis.   Read more...

Gamma-ray Irradiations at the Penn State Radiation Science and  Engineering Center

Candace Davison,¹

Service Provided: Gammacell® Irradiator, ⁶⁰Co Pool  

Sponsors:  Numerous federal, state, and industrial organizations

Gamma-rays from radioactive cobalt-60 are used for a wide variety of applications in many research areas such as sterilization, cryo-reduction, genetic changes, and radiation effects on biological systems, electronics or materials. In addition, gamma-rays cause chemical and/or material changes such as radiolysis, electron trapping, chemical bond changes, cross-linking and polymerization.   Read more...

Spectroscopic Characterization of Cryoreduced Metalloenzymes

Maria-Eirini Pendelia,¹ Alexey Silakov,¹ Squire J. Booker,^{1, 2} J. Martin Bollinger, Jr.,^{1, 2} Carsten Krebs,^{1, 2}

Service Provided:  Gamma Cell Irradiator

Sponsors:  National Institutes of Health, National Science Foundation

Enzymes that contain transition metal cofactors are widespread in nature and play pivotal roles in almost every aspect of life. The reactions they catalyze are not only of fundamental importance in biology, but are also industrially relevant.   Read more...

Studying Bone Metastasis in Culture

A. Mastro,¹ D. Sosnoski,¹ E. Vogler,²

Service Provided:  Gamma Cell Irradiation

Sponsors:  U.S. Army Medical and Materiel Command Breast Cancer Research Program, Susan Komen Foundation, METAvivor Foundation

Breast cancer and several other cancers have a predilection to metastasize to the skeleton [1]. It is estimated that as many as 30 percent of women treated for breast cancer will have a recurrence, and that about 70 percent of these will develop bone metastases.   Read more...

Optical Fiber-Based Pressure Sensor for Power Plant Applications

Karl Reichard,¹ Mark Turner,¹

Service Provided:   Gammacell® Irradiator

Sponsors:  Electric Power Research Institute

This project investigated the application of optical fiber Bragg sensors for gauge and differential pressure sensing in nuclear power plant applications. An emphasis was placed on developing a sensor package with a form factor similar to existing nuclear power industry pressure transmitters.   Read more...