We present the first results from a rotating Michelson-Morley experiment that
uses two orthogonally orientated cryogenic sapphire resonator-oscillators
operating in whispering gallery modes near 10 GHz. The experiment is used to
test for violations of Lorentz Invariance in the frame-work of the photon
sector of the Standard Model Extension (SME), as well as the isotropy term of
the Robertson-Mansouri-Sexl (RMS) framework. In the SME we set a new bound on
the previously unmeasured κ~e−ZZ component of
2.1(5.7)×10−14, and set more stringent bounds by up to a factor of 7
on seven other components. In the RMS a more stringent bound of
−0.9(2.0)×10−10 on the isotropy parameter, PMM=δ−β+1/2 is set, which is more than a factor of 7 improvement. More detailed
description of the experiment and calculations can be found in: hep-ph/0506200Comment: Final published version, 4 pages, references adde