SNS project-wide beam current monitors

The Spallation Neutron Source 1 (SNS) to be constructed at ORNL is a collaboration of six US National Laboratories. Beam current monitors for SNS will be used to monitor H-minus and H-plus beams ranging from 10mA (tune-up in the Front End, Linac and HEBT) to over 60 A fully accumulated in the Ring and RTBT. The time structure of the beams to be measured range from 645nsec "mini" bunches, at the 1.05MHz Ring revolution rate, to an overall 1ms long macro pulse. While the beam current monitors for the SNS have requirements depending upon their location within the system, the development of a unified approach to satisfy requirements of the various locations with common components is a major design objective. This paper will describe the development of the beam current monitors. Various approaches considered for the detectors and signal conditioning will be presented.