azelio.bori...@screen.it wrote: >Data: 03/09/2012 21.53 >Remember the man with two clocks: here we are in the same situation. We >cannot tell which of the two is being screwed up or maybe both...
This is a different case. No matter what each clock does, what matters is the variation of the difference of rates, the variation, not the difference itself. >Interesting experiment but I think it would be better if a >third clock was involved, for example a Cs reference. A four-atomic-clock test including an Rb, two Cs and an H maser had been done at another eclipse with null result, but the clocks were at the same location. What is new with this test is that it involves a GPSDO and hence a virtual clock elsewhere. Antonio I8IOV > >On Mon, Sep 3, 2012 at 9:16 PM, iov...@inwind.it <iov...@inwind.it> wrote: > >> Dear time-nuts, >> a friend of mine, Prof. Alexander Pugach (1), did an experiment on January >> 15, >> 2010, comparing a Rb standard to a GPSDO during a solar eclipse. The >> experimenal site was Kiev, Ukraine. >> >> With reference to the attached graph, his text is (note: the red curve >> belongs >> to another test; the curve which matters here is the bold blue one): >> >> **************************** >> Dear colleagues, >> An experiment has been made aiming to investigate, how the “daily rate of >> clock” varies during a solar eclipse on 01.15.2010. >> In our observatory the high-precision rubidic standard (RbSt) of frequency >> is >> exploited. Its indications were compared to a basic frequency from highly >> stable GPS receiver TRIMBLE Thunderbolt Е. The difference obtained is >> noted as >> “residue” and expressed in nanoseconds (ns). >> This residue was conventially set equal to 0 ns at 00h 00m 13.01.2010. The >> mean “daily rate of RbSt” equals 2740 ns/d, i.e. 3.17 10-11. In the >> Figure >> this rate is shown with blue dashed line. What we have really registered is >> shown with the bold blue curve. >> The main minimum of this difference approximately coincided with the >> eclipse >> start on the Earth. The derivative on site А-В is approximately 6 times as >> much as mean “daily rate of RbSt”. >> ............ >> 19.02.2010 >> **************************** >> >> Apparently, the difference of rate of the two clocks varied by some 4000 >> ns, A >> to B, in the 6 hours of duration of the eclipse (s to e = start to end of >> eclipse at earth, T1-T4 =eclipse in Kiev). >> I would ask you time-nuts, if such a variation could be simply due to an >> occasional sum of "ordinary" adverse factors such as temperature, >> holdover, sky >> view, multipath, etc.., or it is really too large to be explained that way. >> Sorry, I've no idea of what would be the worst case for any of the above >> factors. >> >> Thanks, >> Antonio I8IOV >> >> (1) Prof. Pugach is a senior astronomer at the Academy of Sciences of >> Ukraine. >> >> _______________________________________________ >> 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. >> >_______________________________________________ >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. _______________________________________________ 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.