[time-nuts] Speedy neutrino puzzle solved

Magnus Danielson magnus at rubidium.dyndns.org
Sun Oct 16 00:31:38 UTC 2011

On 10/16/2011 01:59 AM, iovane at inwind.it wrote:
>> From  mikes at flatsurface.com, Oct 16,2011, 01.50
>> At 05:46 PM 10/15/2011, Jim Palfreyman wrote...
>>> http://nbcu.mo2do.net/s/18488/29?itemId=tag:dvice.com,2011://3.
> 83661&fullPageURL=/archives/2011/10/speedy-neutrino.php
>>> Comments please!
>> What an annoying website.
>> Here's a better source, without all the unnecessary pagination and
>> pablum. http://arxiv.org/abs/1110.2685
> Well, the title of the paper is "Times of Flight between a Source and a
> Detector observed from a GPS satelite". From a single GPS satellite? Does this
> make any sense?

Therein lies the prime weakness of that paper. It assumes that a single 
GPS bird was used, while in fact many was being used. It is an expansion 
of the statement:

> The Cs4000 oscillator provides the reference frequency to the PolaRx2e receiver, which is
> able to time-tag its “One Pulse Per Second” output (1PPS) with respect to the individual GPS
> satellite observations.

However, more usefull information follows:

> The latter are processed offline by using the CGGTTS format [19]. The
> two systems feature a technology commonly used for high-accuracy time transfer applications
> [20]. They were calibrated by the Swiss Metrology Institute (METAS) [21] and established a
> permanent time link between two reference points (tCERN and tLNGS) of the timing chains of
> CERN and OPERA at the nanosecond level. This time link between CERN and OPERA was
> independently verified by the German Metrology Institute PTB (Physikalisch-Technische
> Bundesanstalt) [22] by taking data at CERN and LNGS with a portable time-transfer device [23].
> The difference between the time base of the CERN and OPERA PolaRx2e receivers was
> measured to be (2.3 ± 0.9) ns [22]. This correction was taken into account in the application of
> the time link.

(Both quotes is from page 9 in the OPERA paper)

For me, this reads out that they use common view for comparison of the 
cesium clocks, in which case main part of the time sent from the 
satelite would in fact cancel, and I also expect even more detailed 
effects like ionspherics is being canceled, which was not even covered.

More details both of the processing actually done would assist, but I 
assume it will cover many of the relative effects that GPS time 
involves. However, this paper did not really provided a good insight 
into that.


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