72 research outputs found
The IsoDAR high intensity H2+ transport and injection tests
This technical report reviews the tests performed at the Best Cyclotron Systems, Inc. facility in regards to developing a cost effective ion source, beam line transport system, and acceleration system capable of high H[subscript 2][superscript +] current output for the IsoDAR (Isotope Decay At Rest) experiment. We begin by outlining the requirements for the IsoDAR experiment then provide overviews of the Versatile Ion Source (VIS), Low Energy Beam Transport (LEBT) system, spiral inflector, and cyclotron. The experimental measurements are then discussed and the results are compared with a thorough set of simulation studies. Of particular importance we note that the VIS proved to be a reliable ion source capable of generating a large amount of H[subscript 2][superscript +] current. The results suggest that with further upgrades, the VIS could potentially be a suitable candidate for IsoDAR. The conclusion outlines the key results from our tests and introduces the forthcoming work this technical report has motivated.National Science Foundation (U.S.) (PHY-1148134)Massachusetts Institute of Technology (Seed Fund)Massachusetts Institute of Technology (Bose Fellowship
A New Family of High-Current Cyclotrons for Isotope Production
We have developed a new family of compact cyclotrons designed to accelerate
record-high currents of ions with charge-to-mass of 1/2. We have detailed
engineering designs for a 5 mA H2+ cyclotron (delivering 10 mA of protons) and
are extending this concept to 5 mA of deuterons (D+). The innovations enabling
the high currents are: 1) bunching with an RFQ that enables efficient capture
and 2) space-charge-mitigated stable bunch formation established in the first
few turns. These developments can be applied to cyclotron from 5 to around 60
MeV/amu. A 20 MeV/amu deuteron cyclotron would be effective for 225Ac
production via (n,2n) with fast neutrons generated by deuteron breakup in
beryllium.Comment: 22 pages, 9 figures, paper to be submitted to the Journal of
Radioanalytical and Nuclear Chemistry, as part of the Proceedings of the 11th
International Conference on Isotopes, held in Saskatoon, Canada, July 202
Comparison of extraction and beam transport simulations with emittance measurements from the ECR ion source venus
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Snowmass21 Accelerator Modeling Community White Paper
After a summary of relevant comments and recommendations from various reports
over the last ten years, this paper examines the modeling needs in accelerator
physics, from the modeling of single beams and individual accelerator elements,
to the realization of virtual twins that replicate all the complexity to model
a particle accelerator complex as accurately as possible. We then discuss
cutting-edge and emerging computing opportunities, such as advanced algorithms,
AI/ML and quantum computing, computational needs in hardware, software
performance, portability and scalability, and needs for scalable I/O and
in-situ analysis. Considerations of reliability, long-term sustainability, user
support and training are considered next, before discussing the benefits of
ecosystems with integrated workflows based on standardized input and output,
and with integrated frameworks and data repositories developed as a community.
Last, we highlight how the community can work more collaboratively and
efficiently through the development of consortia and centers, and via
collaboration with industry
The DIANA underground accelerator facility project at DUSEL laboratory
The DIANA project (Dakota Ion Accelerators for Nuclear Astrophysics) is a collaboration between the University of Notre Dame, Colorado School of Mines, Regis University, University of North Carolina, Western Michigan University, and Lawrence Berkeley National Laboratory, to build a next generation nuclear astrophysics accelerator facility deep underground. The DIANA accelerator facility is being designed to achieve large laboratory reaction rates by delivering high ion beam currents (up to 100 mA) to a high density (up to 1018 atoms/cm2), super-sonic jet-gas target. The accelerator developments of the DIANA facility are presented here
High-Pitch, Low-Voltage and Low-Iodine-Concentration CT Angiography of Aorta: Assessment of Image Quality and Radiation Dose with Iterative Reconstruction
Objective: To assess the image quality of aorta obtained by dual-source computed tomography angiography (DSCTA), performed with high pitch, low tube voltage, and low iodine concentration contrast medium (CM) with images reconstructed using iterative reconstruction (IR). Methods: One hundred patients randomly allocated to receive one of two types of CM underwent DSCTA with the electrocardiogram-triggered Flash protocol. In the low-iodine group, 50 patients received CM containing 270 mg I/mL and were scanned at low tube voltage (100 kVp). In the high-iodine CM group, 50 patients received CM containing 370 mg I/mL and were scanned at the tube voltage (120 kVp). The filtered back projection (FBP) algorithm was used for reconstruction in both groups. In addition, the IR algorithm was used in the low-iodine group. Image quality of the aorta was analyzed subjectively by a 3-point grading scale and objectively by measuring the CT attenuation in terms of the signal- and contrast-to-noise ratios (SNR and CNR, respectively). Radiation and CM doses were compared.Results: The CT attenuation, subjective image quality assessment, SNR, and CNR of various aortic regions of interest did not differ significantly between two groups. In the low-iodine group, images reconstructed by FBP and IR demonstrated significant differences in image noise, SNR, and CNR (p<0.05). The low-iodine group resulted in 34.3% less radiation (4.4 ± 0.5 mSv) than the high-iodine group (6.7 ± 0.6 mSv), and 27.3% less iodine weight (20.36 ± 2.65 g) than the high-iodine group (28 ± 1.98 g). Observers exhibited excellent agreement on the aortic image quality scores (κ = 0.904). Conclusions: CT images of aorta could be obtained within 2 s by using a DSCT Flash protocol with low tube voltage, IR, and low-iodine-concentration CM. Appropriate contrast enhancement was achieved while maintaining good image quality and decreasing the radiation and iodine doses
Radiation dose reduction based on CNR index with low-tube voltage scan for pediatric CT scan: experimental study using anthropomorphic phantoms
Efficacy of a dynamic collimator for overranging dose reduction in a second- and third-generation dual source CT scanner
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