Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Compton-draft
Document related concepts
Transcript
A Fabry-Perot Cavity for Compton Polarimetry Botao Jia, Sirish Nanda, and Diana Parno on behalf of the Compton Polarimetry Group Optical setup Mirror We use lenses, mirrors and other optical devices to steer the laser beam into the Fabry-Perot cavity, where it is trapped between two mirrors. Green Laser Photodetector Faraday Isolator Fabry-Perot Cavity Photodetector Electro-optical Modulator Compton Polarimetry Electron detector detects scattered electrons Fabry-Perot cavity amplifies laser power by bouncing light between two mirrors Lens Beamsplitter Half-wave Plate Mirror The Fabry-Perot cavity By measuring how electron spins are lined up in the electron beam, we can study the structure of protons, neutrons and nuclei. Compton polarimetry lets us make this measurement by scattering the electron beam on laser photons trapped in a Fabry-Perot cavity. Unscattered electrons continue on original path Electron beam Magnetic dipoles bend the electron beam Lens Wavelength 532 nm (green) Power 3000 Watts Gain 15,000 Length 0.85 m Laser light bounces between two special mirrors that reflect 99.9937% of the light that hits them. This increases the photon intensity by a factor of 15,000 and allows us to take accurate polarimetry measurements. The mirror position must be stable at a subatomic level. Photon detector detects scattered photons Light waves inside a Fabry-Perot cavity
