> Tom, > > The conceptual deadlock that I would overcome is whether > adjusting the C-field the Cs resonance varies, as this would > impact the defition of the "second". > > Thanks, > Antonio I8IOV
Correct, the C-field can vary and it has a slight impact on the accuracy of the seconds that your Cs clock is generating. So that's why it's very important for the best of primary standards to get the C-field right. And they do. Half the work is making a stable clock; the other half is understanding what apparatus you have made and turning it into an accurate clock, with a detailed series of experiments. If you really get into the details of the physics, remember that no commercial or laboratory Cs clock actually resonates at precisely 9 192 631 770.000 Hz. There are corrections for magnetic fields, velocity of atoms, temperature, cavity design, even for gravity; a whole bunch of interesting effects. For a great example of the level of care that goes into the design and calibration of a primary cesium standard read papers like: < Accuracy evaluation of NIST-7> http://tf.nist.gov/timefreq/general/pdf/1497.pdf <Accuracy evaluation of NIST-F1> http://tf.nist.gov/timefreq/general/pdf/1823.pdf Or, for an informal description of C-field and Cs standards see: <HP 5062C Theory of Operation> http://www.leapsecond.com/museum/hp5062c/theory.htm /tvb _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
