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Merged Puzzling results from CERN

Olowkow said:
Why could they not just deduce that this was the problem? It must be very complicated from a troubleshooting point of view. Just my opinion.
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Part of the problem may be that a loose cable is in an uncertain state. You were previously counting on the idea that "the timing-chain that timestamped all the particles" is in the same as "the timing-chain that we spent months checking delays in". Maybe the cable was tight during datataking and loose during the time-delay calibration, or maybe it was loose the whole time.
 
Olowkow said:
Why could they not just deduce that this was the problem? It must be very complicated from a troubleshooting point of view. Just my opinion.
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Apparently two separate probems have been identified, acting to an uncertain degree in opposite senses.

Troubleshooting that kind of situation is, indeed, a bitch.
 
Very funny, a self referencing article.

It is a timing loop.

All the delays are incorporated in the loop.

I send you a signal, 5 nanosconds later you send me back a signal over the same loop. I know the length and the response of the loop.

I physically measure the distance of the experiment.


The two clocks are synchronized by the distance not the one way timing of a signal.
 
A bad connection tends to cause a lot of jitter, you wouldn't get a good lock on cable timing and you would know that you had a problem.
 
A bad cable and a timestamp.

The cable was stable or their loop wouldn't have been stable .

The time stamp removes the loop delay.

Fix the cable and the time stamp changes.

Duh, that is what it is supposed to do if the loop timing changes.
 
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You verify the loop through your local clock. Your loop timing includes all the delays. If you don't get a match between how each clock measured the cable, you work on it until it does.
 
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My bad, not measure the cable.

How each clock measured the loop. The rise time may have been off (slow) but the loop would have compensated as long as it remained stable.
 
They should have been using some of that magic golden cable all the audiophile woo-woos use... :rolleyes:
 
The "coordinator" of the OPERA experiment has resigned.

http://news.yahoo.com/speed-light-experiment-professor-resigns-112219270.html

Doesn't say if he resigned due to this episode, but the timing is interesting.

As an interested bystander this wouldn't appear to be the kind of mistake that should end a career. I would think it is to be expected once in a while and that deailing with it honestly (which appears to have happened) would be all that's expected.
 
RecoveringYuppy said:
As an interested bystander this wouldn't appear to be the kind of mistake that should end a career. I would think it is to be expected once in a while and that deailing with it honestly (which appears to have happened) would be all that's expected.
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I very much doubt it ends his career. If there's any connection between the neutrino experiment and the resignation, it's probably more for the sake of how OPERA appears in the media rather than anyone's career in the scientific field proper.
 
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