CERN / CMS Collaboration
A computer graphic shows a typical Higgs boson candidate event, including two high-energy photons whose energy (depicted by red towers) is measured in the Compact Muon Solenoid's electromagnetic calorimeter. The yellow lines are the measured tracks of other particles produced in the collision. The pale blue volume represents the CMS' crystal calorimeter barrel.
By Alan Boyle
A week ago, sources started passing the word that physicists were "fired up" about further evidence for the existence of the Higgs boson, the last undiscovered particle predicted by the Standard Model and the main quarry for the $10 billion Large Hadron Collider.
That blaze of buzz reached a high point this week, when Columbia mathematician Peter Woit reported "reliable rumors"?that the confidence level for a detection of the Higgs' signature in the mass range of around 125 billion electron-volts, or 125 GeV, was increasing.
"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?" Woit wrote.
"Sigma" refers to the statistical confidence that a given result is more than a fluke, with 5 sigma serving as the gold standard for a discovery. If you're a Higgs-watcher, you'll be hearing a lot about sigma in the next couple of weeks, leading up to the International Conference on High-Energy Physics, or ICHEP, in Australia from July 4 to 11. That's when the LHC's teams are due to provide a status report on the search for the Higgs.?
The Higgs hunt is hot because physicists have hypothesized about the boson for 40 years as part of the mechanism by which some particles acquire mass while others don't. The Higgs is so fundamental to the frontier of physics that Fermilab's Leon Lederman once called it the "God Particle"?? a term that most other physicists positively hate.?Finding it in the mass range where it's expected to be would serve as solid confirmation for the Standard Model, one of the most successful theories in the history of science. Not finding it would be more interesting: Physicists would have to consider some other mechanism, outside the Standard Model, to explain particle mass. And there's nothing theorists love more than a challenge like that.
In December, the teams behind the ATLAS and CMS detectors reported "tantalizing hints" of a Higgs detection at 125 GeV, with confidence levels of 3.6 sigma for ATLAS and 2.6 sigma for CMS. If the additional observations made since then show the same sorts of hints, those sigma levels should go up?? and that's been the gist of the buzz over the last week or so. For science geeks, that's a big deal, or at least a big meme: so big that the hashtag #HiggsRumors was for a time on top of Twitter's trending list, Discovery News' Jennifer Ouelette noted.
A lot of that trending took place because of the in-jokes spawned by the original buzz ??which has now fallen to a steady hum, thanks to a string of reality checks.
"Please do not believe the blogs," ATLAS spokeswoman Fabiola Gianotti told The New York Times. "I am very surprised that rumors appear on a subject that is really evolving daily," CMS spokesman Guido Tonelli told Science News. "The experimenters can't possibly have their data in presentable form yet, so the rumors can't be correct in every detail," Rutgers theoretical physicist Matt Strassler observed on his blog.
Union College physicist Chad Orzel, the author of "How to Teach Relativity to Your Dog," said the celebrity-level hype was?"the price of success":
"I mean, it?s not an accident that there?s a lot of excitement about the maybe-sorta-kinda discovery of the Higgs. This is the product of years of relentless hype from the particle physics community. They've been talking about this goddamn particle for longer than I've been running this blog, and it's finally percolated out into the general public consciousness enough that buzz about it can trend on Twitter. Complaining that your persistent effort to get people to care about particle physics esoterica has led to people being excited about particle physics esoterica seems more than a little churlish.
"So, lighten up. Revel in the success of your hype machine. God knows, if there were a Twitter trending topic about Bose-Einstein Condensation or anything else in atomic physics, I?d do the Happy Dance all the way down the hall. You?ve worked hard to make your elusive particle a celebrity, now reap the rewards."
The true reaping will come in a couple of weeks.?As Reuters' Robert Evans reported, the most recent readings from ATLAS and CMS are being analyzed in isolation, so that one team's conclusions don't influence the other team. Until the ICHEP actually takes place, hype is just about all we'll hear about. But in the meantime, get ready for the real news by reviewing these resources:
Update for 1 p.m. ET June 22: Europe's CERN particle-physics center just announced that the big update on the Higgs search will come on July 4, during a seminar at 3 a.m. ET that's tied to the start of the ICHEP conference.?
"We now have more than double the data we had last year," CERN's director for research and computing, Sergio Bertolucci, was quoted as saying. "That should be enough to see whether the trends we were seeing in the 2011 data are still there, or whether they?ve gone away. It?s a very exciting time."
CERN said that if a new particle is discovered, the ATLAS and CMS teams will need more time to ascertain whether it's the Higgs.
"It's a bit like spotting a familiar face from afar," CERN Director General Rolf Heuer explained. "Sometimes you need closer inspection to find out whether it?s really your best friend, or actually your best friend's twin."
CERN said physicists at the conference in Melbourne will be able to join the seminar via a live two-way link. The seminar will be followed by a news conference at CERN. There'll be a webcast available via?http://webcast.cern.ch. Stay tuned...
Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the?Cosmic Log page?to your Google+ presence. You can also check out?"The Case for Pluto,"?my book about the controversial dwarf planet and the search for new worlds.
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