A commenter here reports that a CERN video announcing that “We have observed a new particle” was released early, and is available here. Note that the language used refers to “observation” NOT “discovery”, indicating that CERN has decided on a version of the 5 sigma discovery criterion that has not yet been met. “Observation” generally means a lower standard of evidence such as 3 sigma. However, it appears that they are sensibly playing this down, with nothing in the video mentioning the word “discovery” or their decision not to use that word. Most physicists likely will however use “discovery” to describe these results, since the combined CMS/ATLAS results should be way beyond 5 sigma (look to Philip Gibbs tomorrow for exact numbers).
In the video, there is reference to “very very strong evidence” for a narrow peak in gamma-gamma (presumably above 4 sigma, close to 5 sigma in each experiment), as well as “also evidence” for ZZ (4 sigma?) and “less conclusive” evidence in other channels.
Immediate Update: The word here is that CERN is claiming that this is just one of multiple videos made to cover all eventualities. Maybe tomorrow’s version will substitute “discovery” for “observation”…
Update: As commenter Tim points out, this is a CMS video, not a CERN one, so it just refers to CMS results. Evidently CMS is not claiming “discovery”, but that doesn’t mean ATLAS doesn’t have slightly better results and will make a discovery claim. Also, it doesn’t show what CERN will say about the joint results of the two experiments.
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