Sync Lite 2 @ Work

General Description
 
The Sync Lite system measures the x and y profiles of the p and pbar beam by measuring the synchrotron light emitted at the edge of a tevatron dipole magnet. The light emitted by the protons at the upstream end of the dipole is deflected about 2.5cm from the beam at the downstream end. Since the beam sigma is about 0.5mm the light can be picked off with a mirror. Light from the pbar beam from a neighbouring dipole is picked off by a separate mirror near the same region. Via an array of mirrors the light from the p and pbar are detected in two separate telescopes.

The x and y projections of the beam profiles are well fit to a Gaussian with a linear background and results reported are based on this fit. If the profile is not circular (i.e. an ellipse), then one can perform a 2D fit and get the tilt (if any) of the ellipse relative to the x or y axis.

 The detection is achieved with a photocathode, a microchannel plate (MCP) intensifier followed by a phosphor screen and a CID camera. The camera integrates over about 30ms. The video signal is sent to a MAC with a video frame grabber that acts as an 8-bit ADC for each xy channel.

The system sends an array of numbers to the control room which include for all 36 bunches and both the p and pbar, the (x,y) positions and sigma.
   

Maintained by Harry Cheung Last updated: Tuesday, September 3, 2002 21:53
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