Interferometric measurements of 127I2 reference frequencies for 1S-2S spectroscopy in muonium, hydrogen, and deuterium

[[abstract]]The frequencies of three Doppler-free absorption lines of the 127I2 molecule in the vicinity of 730 nm have been measured interferometrically with reference to an iodine-stabilized 633-nm He-Ne laser. These frequencies are important as transfer standards for Doppler-free, two-photon spectroscopy of the 1S-2S transitions in muonium, hydrogen, and deuterium (with the use of frequency tripling to generate the necessary 244-nm radiation). The a15 component of the R(26) 5-13 transition has recently been used as a reference line in a high-precision measurement of the muonium 1S-2S frequency interval. Under the conditions reported, the frequency of this transition was found to be 409253981.70 (0.14) MHz, ~680 MHz away from the muonium transition[[fileno]]2010112010021[[department]]物理