[QUICK UPDATE April 2: I’ve now finished an article giving more details of how OPERA, with LVD’s help, solved the mystery.]
[UPDATE March 31 2 a.m.: following study of the slides from a mini-workshop recording the results of investigations by OPERA and LVD, I now have the information to remove all the guesswork from my original post; you’ll see outdated information crossed out and newer and more precise information written in orange. I’ve also added figures from the talks.]
March 30 5:30 p.m. Two main scientists at OPERA, one leading the OPERA team as a whole and the other leading the neutrino speed measurement, resigned their leadership positions today. The suggestion from the press is that this is due to personal and scientific conflicts within the OPERA experiment, rather than due directly to the errors made in the neutrino speed experiment; but of course the way the measurement was publicized by OPERA caused serious internal conflicts at the time and are surely part of the issue. [Oh, and meanwhile, back over at the CERN lab, some good news: collisions at the Large Hadron Collider with 8 TeV of energy per collision were achieved this afternoon.]
The mystery surrounding OPERA, the Gran Sasso experiment which (apparently through a technical problem) measured that neutrinos sent from the CERN lab to the Gran Sasso lab in Italy arrived earlier than expected by 60 nanoseconds,
seems to be on the verge of being is resolved. Statements made by an OPERA scientist in the Italian language press, pointed out to me by commenters (Titus and A.K.), seem to imply that OPERA has more or less confirmed that the problematic fiber optic cable (along with the clock problem, to a lesser extent) was responsible for a 60 nanosecond (billionth-of-a-second) shift in the timing, creating the false result. We do not yet have official information from OPERA about this, but talks given at a mini-workshop a couple of days ago make clear that this is the case.
The way this was done
if I/we understand the Italian correctly is something like is the following with all details still very uncertain.