Search NASASearch

SEARCH · Search NASA

Results for “LCD”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

Record of Decision: H - LEBT Design Modifications

The LAMP Conceptual Design (LCD) is described in the LAMP Conceptual Design Report. The proposed new configuration of the LAMP H - LEBT encompasses multiple changes to the LCD. The new configuration makes use of a single H - source to supply beam to all LANSCE user stations except IPF; this eliminates one of the H - sources in the LCD, and the associated pulsed merger magnet the use of two such sources required. The source current from the sole H - source is gated on a macropulse-by-macropulse basis using techniques demonstrated at SNS (Spallation Neutron Source), specifically, changes to the RF plasma drive power. A pulsed electrode system is used to match the beam into the LEBT transport line, variable on a macropulse-by-macropulse basis to match the source beam current.

43 PARTICLE ACCELERATORS

Using convolutional neural networks to accelerate three-dimensional coherent synchrotron radiation computations

Calculating the effects of coherent synchrotron radiation (CSR) is one of the most computationally expensive tasks in accelerator physics. Here, we use convolutional neural networks (CNNs), along with a latent conditional diffusion (LCD) model, trained on physics-based simulations to speed up calculations. Specifically, we produce the 3D CSR wakefields generated by electron bunches in circular orbit in the steady-state condition. Two datasets are used for training and testing the models: wakefields generated by three-dimensional Gaussian electron distributions and wakefields from a sum of up to 25 three-dimensional Gaussian distributions. The CNNs are able to accurately produce the 3D wakefields ∼250–1000 times faster than the numerical calculations, while the LCD achieves a gain of a factor of ∼34. We also test the extrapolation and out-of-distribution generalization ability of the models. They generalize well on distributions with larger spreads than what they were trained on but struggle with smaller spreads.

43 PARTICLE ACCELERATORS

Record of Decision: MEBT Energy Change

The LAMP Conceptual Design (LCD), as described in the LAMP Conceptual Design Report incorporates a radiofrequency quadrupole (RFQ) with an output beam energy of 3.0-MeV; the medium energy beam transport line (MEBT) transports beam from the end of the RFQ into the first LAMP drift tube linac (DTL) tank. The MEBT contains components, such as rebunchers and beam choppers, designed for the specific output energy of the RFQ, and the DTL tank is designed to accept this beam energy.

43 PARTICLE ACCELERATORS

Record of Decision: LEBT Energy Change

The LAMP Conceptual Design (LCD), as described in the LAMP Conceptual Design Report incorporates multiple 100-keV low-energy beam transport (LEBT) lines between the ion sources and the radiofrequency quadrupole (RFQ). The LEBT lines transport H + and H - beams from their respective ion sources to the RFQ entrance, and provide the required manipulations (focusing, steering, chopping, etc.) to the ion beams to prepare them for injection into the RFQ and further acceleration.

43 PARTICLE ACCELERATORS