Just got out of 8 days in the Grand Canyon which was spectacular,
Reliable rumors couldn’t wait, and they indicate that the experiments are seeing much the same thing as last year in this year’s new data: strong hints of a Higgs around 125 GeV. The main channel investigated is the gamma-gamma channel where they are each seeing about a 4 sigma signal.
More later when I reach civilization.
Update: Back in civilization, or at least New York City. The above was the first posting I’ve ever written on an iphone, late at night. Now I have a real keyboard, so I can write a bit more. The “4 sigma signal” refers to the combined 2011 and new 2012 data. To oversimplify the situation, last year both experiments were seeing roughly a 3 sigma excess in gamma-gamma around 125 GeV. This was enough to convince many people that it was highly likely that this was the Higgs. However, that size excess is not completely convincing, it is not unheard of for there to be statistical flukes of such size.
The 2012 data that is being analyzed for ICHEP is of a similar size to the 2011 data. If 2011 was a fluke, you expect to see nothing much around 125 GeV in the 2012 data. If the 2011 signal really was the Higgs you expect the signal to strengthen. What I’m hearing from both experiments is that they are seeing an excess in the new data, strengthening the significance of the signal.
Exactly how much data they’ll have analyzed by ICHEP and exactly what the significance of the signal in the gamma-gamma channel will be (as well as what other channels will show) is still to be seen. CERN will soon have to decide how to spin this: will they announce discovery of the Higgs, or will they wait for some overwhelmingly convincing standard to be met, such as 5 sigma in at least one channel of one experiment? The bottom line though is now clear: there’s something there which looks like a Higgs is supposed to look. Attention will soon move to seeing if this signal is exactly what the SM predicts (e.g. will the excesses in different channels agree with SM predictions?).
More details about this from Philip Gibbs (who is speculating about what will be announced), and from Tommaso Dorigo (who is keeping quiet about what he knows, but providing context for what the ICHEP announcements will mean).
Update: Matt Strassler has more about this here. He provides about 20 links to his own blog, no link to the source of his information (this posting). It appears that this is because I’m a “non-particle-physicist blogger” engaged in a conspiratorial plot with some of the 6000+ people who know this latest news to “subvert the scientific process” by sharing it with others.
Update: There are stories about this at Wired, New Scientist and the New York Times. The New York Times article emphasizes that the Higgs results are now “Shrouded in Secrecy”, with the spokeswoman for ATLAS pleading “Please do not believe the blogs”.
According to Matt Strassler “the experimentalists can’t possibly have their data in presentable form yet, so the rumors can’t be correct in every detail”. To clarify any confusion
“Exactly how much data they’ll have analyzed by ICHEP and exactly what the significance of the signal in the gamma-gamma channel will be (as well as what other channels will show) is still to be seen”
means that the above rumors were based on just part of the data (significantly less than half in the ATLAS case, somewhat more than half in the CMS case).
Update: I think I’m too old to ever really understand Twitter, but it seems that #HiggsRumors is a “Trending Topic”, whatever that means. More explanation available from Jennifer Ouellette, and sensible commentary from Chad Orzel.
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