Publications

This paper describes the hardware changes made to the triggering system of the HERMES III accelerator at Sandia National Laboratories, New Mexico. The HERMES III accelerator is a gamma ray simulator producing 100 kRad dose per shot with a full width half max pulse duration of approximately 25 nanoseconds and averaging six shots per day. For each accelerator test, approximately 400 probe signals are recorded over approximately 65 digitizers. The original digitizer trigger system employed numerous independent legacy signal generators resulting in non-referenceable digitizer time bases. We detail our efforts to reference the digitizer time bases together using a modular and scalable approach with commercial-off-the-shelf components. This upgraded trigger system presently measures a maximum digitizer trigger time spread of less than two nanoseconds across the 65+ digitizers. This document details the hardware changes, provides a summary of the accelerator charging process, presents 'one-line' trigger system diagrams and summarizes the times of interest for a typical HERMES accelerator shot.

Abstract not provided.

Abstract not provided.

Abstract not provided.

The HERMES III accelerator, which is located at Sandia National Laboratories' Tech Area IV, is the largest pulsed gamma X-ray source in the world. The accelerator is made up of 20 inductive cavities that are charged to 1 MV each by complex pulsed power circuitry. The firing time of the machine components ranges between the microsecond and nanosecond timescales. This results in a variety of electromagnetic frequencies when the accelerator fires. Testing was done to identify the HERMES electromagnetic noise signal and to map it to the various accelerator trigger events. This report will show the measurement methods used to capture the noise spectrum produced from the machine and correlate this noise signature with machine events.

Abstract not provided.

Abstract not provided.