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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,225 records · Page 68
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Construction and Test of a Novel Superconducting RF Electron Gun

The University of Wisconsin-Madison has completed installation of a superconducting electron gun. Its concept was optimized to be the source for a CW free electron laser facility with multiple megahertz repetition rate end stations. This VHF superconducting configuration holds the promise of the highest performance for CW injectors. Initial commissioning efforts show that the cavity can achieve gradients of 35 MV/m at the cathode position. With the cathode inserted CW operation has been achieved at 20 MV/m with good control of microphonics, negligible dark current, and Q o > 3xl0 9 at 4 K. Bunch charges of~100 pC have been delivered, and first simple beam measurements made. These preliminary results are very encouraging for production of lOOspC bunches with millimeter-milliradian or smaller normalized emittances. Plans are in place to carry out more definitive studies to establish the full capabilities. However, since the grant was not renewed, the electron gun is currently mothballed, and without supplemental fund the opportunity for further work will be lost.

Bisognano, Joseph P.↗
DOE OSTI2014

Wafer Test Cavity - Linking Surface Microstructure to RF Performance: a ‘Short-­Sample Test Facility’ for characterizing superconducting materials for SRF cavities

The Wafer Test cavity was designed to create a short sample test system to determine the properties of the superconducting materials and S-I-S hetero-structures. The project, funded by ARRA, was successful in accomplishing several goals to achieving a high gradient test system for SRF research and development. The project led to the design and construction of the two unique cavities that each severed unique purposes: the Wafer test Cavity and the Sapphire Test cavity. The Sapphire Cavity was constructed first to determine the properties of large single crystal sapphires in an SRF environment. The data obtained from the cavity greatly altered the design of the Wafer Cavity and provided the necessary information to ascertain the Wafer Test cavity’s performance.

42 ENGINEERING↗
DOE OSTI2015

RF Linac Driven X-ray FEL [Slides]

X-rays are a form of high-energy (300 eV – 30 keV) electromagnetic waves. In X-ray tubes, broadband X-rays (and a few narrow K lines) are generated by ramming electrons at a target to produce Bremsstrahlung (braking radiation).

43 PARTICLE ACCELERATORS↗
DOE OSTI2016

Improving RF Characteristics of Wire: CRADA Final Report

Los Alamos National Laboratory (LANL) and the partner investigated microwave loss characteristics of coated wire made at LANL. The characterization of the coatings was performed using a microwave cavity. The loss characteristics of the coatings was compared to those of bare Cu and Ag wires of the same diameter.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Nautical Dawn - Wide-area Motion Imagery and RF Compressive Sensing Applications: CRADA Final Report

The global information grid (GIG) provides access to massive amounts of data from a vast number of intelligence, surveillance, and reconnaissance (ISR) sensors and sources. A significant challenge exists in the actual exploitation of the sensor data. Sensor data is often large, and in the present paradigm analysts extract information from it in raw form. This approach taxes the limited network-bandwidth of the GIG, since the raw data must be transmitted to analysts prior to processing. The parties proposed a new approach to advance the rate of production of actionable information from ISR data, one that extracts information from raw data closer to the sensors. This research developed an information-centric capability that uses a distributed compressive sensing and processing (DCSP) framework.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2016

Gated Field-Emission Cathode Radio-Frequency (RF) Gun

The goal of this CRADA was to procure the carbon nanotube cathode from Radiabeam, install it in HBESL and make current measurements as a function of the gun gradient. The gun was operated at 1.3 GHz. After testing, send the cathode back to RadiaBeam for surface analysis.

43 PARTICLE ACCELERATORS↗
DOE OSTI2018

Staging For Wakefield Acceleration Experiment Hardware Development: Fast Kicker and High Power RF Delay Section

This project pursues demonstration of the complete staging of high gradient wakefield acceleration at Argonne Wakefield Accelerator (AWA) facility, which is well aligned with the core mission of AWA and the roadmap laid out for the dielectric wakefield accelerator technology toward future linear colliders. During the project, we have successfully demonstrated the feasibility of the staged short pulse TBA (C. Jing, et al, Nucl. Instrum. Meth. A., 898, 72-76, 2018). We have successfully performed the first over 100MW dielectric power extractor. As the last task, one of the key elements for the drive beam distribution system, the fast kicker, has been built and successfully demonstrated this year too. The staging technology demonstrated in this project is crucial for the 500MeV Demonstrator that is planned at AWA in the next five years. The plan is to use two staged meter long dielectric disk accelerators to achieve 500MeV energy gain within ~10 meter long experimental space. While this SBIR project is closed, we plan to continue to investigate the dielectric accelerator technologies under Euclid's general scientific and commercial interests.

43 PARTICLE ACCELERATORS↗
DOE OSTI2018

Conceptual Design Report: Radial RF Injectors for Improved Waste Stream Processing

In June 2017, the US Department of Energy Accelerator Stewardship Program [1] released its “FY2017 Research Opportunities in Accelerator Stewardship” [2], including a call for design studies of four types of high-power electron accelerators for energy and environmental applications. Table 1 lists the target performance for the “Type 1” and “T ype 2” accelerators in this call.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Bremsstrahlung dose rates during the conditioning of the superconducting RF cavities of the NSLS-II storage ring

NSLS-II storage ring currently operates with two single-cell Cornell Electron Storage Ring (CESR) type niobium cavities at 500 MHz with a Q value of 79,000 [1,2] both in one straight section in cell 24. During the maintenance period, the cavities have to be conditioned to be ready for operation. The cavities are source of bremsstrahlung radiation due to the field emission and multipacting processes.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Nb 3 Sn Superconducting RF Cavities: R&D Progress at Fermilab and Opportunities

Nb 3 Sn becomes superconducting at twice as high temperature as our standard SRF material niobium. This allows us to efficiently operate Nb 3 Sn cavities at 4.4 K instead of the usual 2 K. This reduces cryogenic costs and even makes it possible to use a cryocooler instead of a large, complex cryogenic plant. The superheating field H sh of Nb 3 Sn is twice that of niobium. H sh is thought to be the ultimate limit for a defect-free superconductor. Nb 3 Sn cavities being made today are still about a factor of 4 away from this ultimate limit, but R&D has been leading to substantial progress towards this goal.

43 PARTICLE ACCELERATORS↗
DOE OSTI2020

Nb 3 Sn Superconducting RF Cavities: R&D Progress at Fermilab and Opportunities [Poster]

Nb 3 Sn becomes superconducting at twice as high temperature as our standard SRF material niobium. This allows us to efficiently operate Nb 3 Sn cavities at 4.4 K instead of the usual 2 K. This reduces cryogenic costs and even makes it possible to use a cryocooler instead of a large, complex cryogenic plant. The superheating field Hsh of Nb 3 Sn is twice that of niobium. Hsh is thought to be the ultimate limit for a defect-free superconductor. Nb 3 Sn cavities being made today are still about a factor of 4 away from this ultimate limit, but R&D has been leading to substantial progress towards this goal

43 PARTICLE ACCELERATORS↗