Compton Cavity State Identification (d2n)
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Revision as of 16:47, 1 May 2009 by Dseymour (Talk | contribs) (New page: =Background= In the Hall A Compton Polarimeter, Compton scattering occurs inside a Fabry-Perot cavity fed by an infrared (1064 nm) laser. Over the course of a run, the cavity is periodica...)
Background
In the Hall A Compton Polarimeter, Compton scattering occurs inside a Fabry-Perot cavity fed by an infrared (1064 nm) laser. Over the course of a run, the cavity is periodically filled with photons of a given polarization state (right or left circular), drained, and filled with photons of the opposite polarization state.
In order to compute accurate Compton asymmetries, we need a reliable, accurate way of determining the state of the Compton laser cavity during any given mps:
- Is the laser on and locked to the cavity, or unlocked? This is the difference between a few milliWatts of power and 400+ Watts.
- Are the photons in the cavity left-circularly or right-circularly polarized?
