ORNL, Oak Ridge, Tennessee, USA
We are reporting on the latest progress in the longitudinal beam profile and emittance diagnostics development at SNS. In order to characterize the longitudinal phase space of the beam in the SNS 1GeV proton LINAC the bunch profile needs to be measured with a few picosecond resolution. The original SNS set of diagnostics included only four interceptive Feschenko-style longitudinal profile monitors in the normal conducting part of the LINAC at 100MeV. Two recently added systems are: a non-interceptive laser scanner in the injector at 2.5MeV and a novel non-interceptive method for longitudinal Twiss parameters measurement using the beam position monitors in the Super Conducting LINAC (SCL) at 300MeV. This paper presents details of these two diagnostics and discusses their performance, resolution limitations and future development plans.
ORNL, Oak Ridge, Tennessee, USA
ORNL RAD, Oak Ridge, Tennessee, USA
A new Differential and errant Beam Current Monitor (DBCM) is being implemented for the Spallation Neutron Source's Medium Energy Beam Transport (MEBT) and Super Conducting linac (SCL) accelerator sections. This new current monitor will abort the beam when the difference between two toroidal pickups exceeds a threshold. The MEBT DBCM will protect the MEBT chopper target while the SCL DBCM will abort beam to minimize fast beam losses in the SCL cavities. The new DBCM will also record instances of errant beam such as beam drop-outs to assist in further optimization of the SNS Accelerator. A software Errant Beam Monitor was implemented on the regular BCM hardware to study errant beam pulses. The new system will take over this functionality and will also be able to abort beam on pulse to pulse variations. as it is based on the FlexRIO hardware programmed in LabVIEW FPGA and can abort beam in 5 us. This paper describes the development, implementation, and initial test results of the DBCM as well as errant beam examples.
