News from the OPERA

Today, at 15:30 at Physics Department in Milano, Italy, Luca Stanco, one of the 15 OPERA's collaboration who didn't sign the preprint, discussed in a brief presentation (about half an hour, without quests) the OPERA's results. In conclusion we have a lot of interesting informations. He described the experiments, starting from the production of neutrinos' beams and arriving to the detection in Italy, under Gran Sasso mountain. He briefly described the measure of the distance and the GPS system.
The most interesting part of the presentation is the production of neutrinos' beams(1). First of all reasearchers need to produce one proton bench in PS (is a little synchrotron), so they send the bench in SPS, a much greater synchrotron than PS. In order to fill SPS are needed 11 PS benches, but researchers decided to inject in SPS 5 beams (each one with a time length of about 10.4 μs) and after a time range of about 50 ms they inject others 5 benches. So, if we observ with attention the neutrino's signal, we see 5 peaks, a remember of the protons benches that origined the signal. In this process there is one of the criticism: it is necessary to be secure that the proton's probability density function and the neutrino's probability density function are equals. Another important point to clarify is the time of flight(2) or the presence of some effects dued by day/night or seasons.
But the really news arrived in the end of the presentation:
OPERA collaboration decided this morning to postpone the submission of paper of about one month
I lost the first of the two motivation, but the second is simple: CNGS is preparing new benches spaced at 500 ns. So OPERA could have a really first opportunity to test their data.
After Stanco's presentation, the theorist Francesco Villante presented a brief summary of a couple of theoretical work, arriving to the Glashow-Coleman formalism(3, 4). About the theoretical idea of the Nobel Prize (presented also in a rencent preprint) tomorrow will be published on arXiv a note of Villante and Vinesi (probably title will be On the generality of Cohen and Glashow constraints), so I reserve to write a post about this part of the conference in the next days after the reading of this new contribution to the scientific discussion.
In the end I emphasize also one point: during discussion, some people was intrigued by the idea of Mecozzi and Bellini, nevertheless Villante showed the inconsistence of the suggestion. But we have seen yesterday that just Berry, with the... optician Brunner, rejected the idea.
(1) An interesting claim about this point was: the difference between protons speed and neutrinos speed is negligible! I would conclude that it happens something during the flight... if the measure will be reproduced, of course!
(2) There is an interesting update during the discussion: the researchers considered, after the publication of the preprint, the corretion dued by Earth rotation and they observed tath we need to (aumentare) the light's delay about 2 ns.
(3) Coleman and Glashow (1997) Cosmic ray and neutrino tests of special relativity, Phys. Lett. B 405 (arXiv); (1999) High-energy tests of Lorentz invariance, Phys. Rev. D 59 (arXiv)

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