Subject: [Depfis] CERN experiments observe particle consistent with long-sought Higgs boson

From: Daniel de Florian <[email-masked]>
Date: Wed, 4 Jul 2012 05:29:46 -0300 (ART)

CERN experiments observe particle consistent with long-sought Higgs boson

Geneva, 4 July 2012. At a seminar held at CERN* today as a curtain raiser to
the year?s major particle physics conference, ICHEP2012 in Melbourne, the
ATLAS and CMS experiments presented their latest preliminary results in the
search for the long sought Higgs particle. Both experiments observe a new
particle in the mass region around 125-126 GeV.

?We observe in our data clear signs of a new particle, at the level of 5
sigma, in the mass region around 126 GeV. The outstanding performance of the
LHC and ATLAS and the huge efforts of many people have brought us to this
exciting stage,? said ATLAS experiment spokesperson Fabiola Gianotti, ?but a
little more time is needed to prepare these results for publication.?

"The results are preliminary but the 5 sigma signal at around 125 GeV we?re
seeing is dramatic. This is indeed a new particle. We know it must be a
boson and it?s the heaviest boson ever found,? said CMS experiment
spokesperson Joe Incandela. ?The implications are very significant and it is
precisely for this reason that we must be extremely diligent in all of our
studies and cross-checks."

?It?s hard not to get excited by these results,? said CERN Research Director
Sergio Bertolucci. ? We stated last year that in 2012 we would either find a
new Higgs-like particle or exclude the existence of the Standard Model
Higgs. With all the necessary caution, it looks to me that we are at a
branching point: the observation of this new particle indicates the path for
the future towards a more detailed understanding of what we?re seeing in the
data.?

The results presented today are labelled preliminary. They are based on data
collected in 2011 and 2012, with the 2012 data still under analysis. 
Publication of the analyses shown today is expected around the end of July.
A more complete picture of today?s observations will emerge later this year
after the LHC provides the experiments with more data.

The next step will be to determine the precise nature of the particle and
its significance for our understanding of the universe. Are its properties
as expected for the long-sought Higgs boson, the final missing ingredient in
the Standard Model of particle physics? Or is it something more exotic? The
Standard Model describes the fundamental particles from which we, and every
visible thing in the universe, are made, and the forces acting between them.
All the matter that we can see, however, appears to be no more than about 4%
of the total. A more exotic version of the Higgs particle could be a bridge
to understanding the 96% of the universe that remains obscure.

?We have reached a milestone in our understanding of nature,? said CERN
Director General Rolf Heuer. ?The discovery of a particle consistent with
the Higgs boson opens the way to more detailed studies, requiring larger
statistics, which will pin down the new particle?s properties, and is likely
to shed light on other mysteries of our universe.?

Positive identification of the new particle?s characteristics will take
considerable time and data. But whatever form the Higgs particle takes, our
knowledge of the fundamental structure of matter is about to take a major
step forward.

Pictures available here:

http://cdsweb.cern.ch/search?cc=Press+Office+Photo+Selection&rg=100&of=hpm&
p=internalnote%3A%22Higgs%22&sf=year&so=d

Footage available here:

http://cdsweb.cern.ch/search?cc=Press+Office+Video+Selection&rg=100&p=inter
nalnote%3A%22Higgs%22&sf=year&so=d