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arXiv · 0911.4776

The status and prospects of the Q & A experiment with some applications

Hsien-Hao Mei·Wei-Tou Ni·Sheng-Jui Chen·Sheau-shi Pan
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Abstract

Motivated to measure the QED birefringence and to detect pseudoscalar-photon interaction, we started to build up the Q & A experiment (QED [Quantum Electrodynamics] and Axion experiment) in 1994. In this talk, we first review our 3.5 m Fabry-Perot interferometer together with our results of measuring Cotton-Mouton effects of gases. We are uprading our interferometer to 7 m armlength with a new 1.8 m 2.3 T permanent magnet capable of rotation up to 13 cycles per second. We will use 532 nm Nd:YAG laser as light source with cavity finesse around 100,000, and aim at 10 nrad/Hz^{1/2} optical sensitivity. With all these achieved and the upgrading of vacuum, QED birefringence would be measured to 28% in about 50 days. Along the way, we should be able to improve on the dichroism detection significantly.

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Hsien-Hao Mei, Wei-Tou Ni, Sheng-Jui Chen, Sheau-shi Pan. 2009-11-25. The status and prospects of the Q & A experiment with some applications. https://doi.org/10.3204/desy-proc-2009-05/mei_hsien-hao

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