The design and construction of a new fast neutron facility and first dosimetric results obtained from seven neutron beams are presented. The neutrons are produced by bombarding beryllium targets with protons and deuterons from our K = 32 negative ion cyclotron. The dose rate in air 1 m distance from the thick target within a 13 x 13 cm2 field amounts to about 50 cGy/min at 30 microA of 32 MeV protons.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0924-4212(96)84905-x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Ultra-fast single-crystal CVD diamonds in the particle time-of-flight (PTOF) detector for low yield burn-history measurements on the NIF (invited).
Rev Sci Instrum
January 2025
Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
The Particle Time of Flight (PTOF) diagnostic is a chemical vapor deposition diamond-based detector and is the only diagnostic for measuring nuclear bang times of low yield (<1013) shots on the National Ignition Facility. Recently, a comprehensive study of detector impulse responses revealed certain detectors with very fast and consistent impulse responses with a rise time of <50 ps, enabling low yield burn history measurements. At the current standoff of 50 cm, this measurement is possible with fast 14 MeV neutrons from deuterium-tritium (DT) fusion plasmas.
View Article and Find Full Text PDFUnveiling the radiation shielding efficacy of diorite, granodiorite, tonalite, and granite: experimental and simulation study.
Sci Rep
January 2025
Physics Department, Faculty of Science, Fayoum University, Fayoum, Egypt.
For the purpose of this study, four natural rock samples-namely, diorite, granodiorite, tonalite, and granite-are being investigated about their radiation attenuation. The elemental composition of the rocks was obtained through Energy dispersive X-ray spectroscopy (EDX) which examines the microstructural and localized area elemental analyses of the four rock samples. A Monte Carlo simulation (MCNP) was used to determine and evaluate the investigated samples.
View Article and Find Full Text PDFDemonstration of active neutron interrogation of special nuclear materials using a high-intensity short-pulse-laser-driven neutron source.
Sci Rep
January 2025
Los Alamos National Laboratory, Los Alamos, NM, 87544, USA.
Detecting shielded special nuclear material, such as nuclear explosives, is a difficult challenge pursued by non-proliferation, anti-terrorism, and nuclear security programs worldwide. Interrogation with intense fast-neutron pulses is a promising method to characterize concealed nuclear material rapidly but is limited by suitable source availability and proven instrumentation. In this study we have pioneered a demonstration of such an interrogation method using a high-intensity, short-pulse, laser-driven neutron source that offers potential benefits compared to conventional neutron sources.
View Article and Find Full Text PDFA pulsar-like polarization angle swing from a nearby fast radio burst.
Nature
January 2025
Perimeter Institute for Theoretical Physics, Waterloo, Ontario, Canada.
Article Synopsis
- Fast radio bursts (FRBs) are intense signals from deep space that last for milliseconds and share some characteristics with pulsars, suggesting they may originate from neutron stars.
- Despite similarities, FRBs like 20221022A display different patterns in their linear polarization position angle (PA), particularly a 130° rotation that aligns with pulsar behaviors, hinting at magnetospheric origins.
- This study rules out short-period pulsars as potential sources for FRB 20221022A, supporting the idea that its unique PA evolution fits the rotating vector model commonly used for pulsars.
Rebalancing the seed proteome following deletion of vicilin-related genes in pea (Pisum sativum L.).
J Exp Bot
December 2024
Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK.
Null mutations for genes encoding a major seed storage protein in pea, vicilin, were sought through screening a fast-neutron mutant population. Deletion mutations at four or five vicilin loci, where all vicilin genes within each locus were deleted, were combined to address the question of how removal or reduction of a major storage protein and potential allergen might impact the final concentration of protein per unit mature seed weight, seed yield and viability. While the concentration of seed protein was not reduced in mature seeds of mutant lines, indicative of a re-balancing of the proteome, notable differences were apparent in the metabolite, proteomic and amino acid profiles of the seeds, as well as in some functional properties.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!