On Feb 14, 2018 19:47, "Chris Caudle" <[email protected]> wrote:
On Wed, February 14, 2018 7:06 pm, jimlux wrote: > At substantially more expense, and with an experimental lattice clock, Does that schematic figure in the paper imply that the "transportable" strontium and ytterbium clocks are built into trailers instead of the traditional rack enclosure? Actually now that I look more closely it looks like maybe two trailers. Doesn't seem like something that Jim is going to be flying any time soon. Yes. From the Nature article text: "The transportable 87Sr lattice clock is (compared with laboratory clocks) designed to be compact, with robust optical parts12 <https://www.nature.com/articles/s41567-017-0042-3#ref-CR12>. The physics package is less than 0.6 m3 in size, and we use laser breadboards with mechanical stress-resistant fibre couplers21 <https://www.nature.com/articles/s41567-017-0042-3#ref-CR21>. All components except the reference cavity of the interrogation laser are rigidly mounted in a car trailer (size 2.2 m × 3 m × 2.2 m), and vibration isolation is provided by rubber dampers. The trailer interior is temperature stabilized, while the small volume of the trailer hinders air exchange and generates hot spots with more than 10 K temperature rise. However, the optics and the physics package are placed apart and shielded from these and are stable to within 0.4 K after an initial temperature rise of about 1 K. The transportable ultrastable reference cavity for the clock interrogation lasers is rigidly mounted to endure transport12 <https://www.nature.com/articles/s41567-017-0042-3#ref-CR12>. It was placed next to the trailer to avoid its performance being degraded by vibrations induced in the trailer’s air conditioning system. The vibration amplitudes in the trailer are a factor of ten larger than under typical laboratory conditions, leading to a corresponding increase in clock instability. A reference resonator with lower acceleration sensitivity or an active feed-forward system may in the future remedy this inconvenience22 <https://www.nature.com/articles/s41567-017-0042-3#ref-CR22>." Cheers, Tim -- Chris Caudle _______________________________________________ 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. _______________________________________________ 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.
