Hi, Bruce recently mentioned [1], where Fig. 2 shows that the Cs clocks of the old II and IIA birds are less stable than the Rb clocks of the newer birds. This struck me as odd and i tried to find out why a Cs beam had worse stability than a Rb vabor cell. The only paper comparing both clocks that i found was [2] which shows in Fig. 2 that the Cs clocks are less stable even at very small taus. But the only mention of a property that is worse for the Cs than for the Rb mentioned is that the Rb's are temperature stabilized while the Cs is not. But i would expect the temperature effect to be significant from a couple 100s upward, not down to 1s.
Can anyone shed some light on why the GPS Cs beams have a worse stability than the Rb vapor clocks? Attila Kinali [1] "GPS clocks in space: Current performance and plans for the future", by Dass, Freed, Petzinger, Rajan, 2002 http://tycho.usno.navy.mil/ptti/ptti2002/paper18.pdf [2] "Atomic frequency standards for the GPS IIF satelites", by Emmer, Watts, 1997 http://www.pttimeeting.org/archivemeetings/1997papers/Vol%2029_19.pdf -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.