HST2012, CERN - Day 4

Today was a big day. You can imagine how happy we are.

First I feel that I contributed just a little bit, and also all people around the world, for this historical milestone, with my computer time to run data using LHC@home.

About what they said today at the conference is that there's a new boson over there.

In the 60's of the last century, independently, Peter Higgs, Francois Englert, Robert Brout, Gerald Guralnik, Dick Hagen y Tom Kibble, they proposed that the Universe was full filled with a field, and later was called the HIGGS field. The interactions between the particles and this field makes that acquire mass. We can imagine the full scope of these virtual particles (Higgs bosons) that interact with the particles causing some "trouble" to their move. This means that particles acquire mass and inertia. 
But we can not measure directly the Higgs. We must therefore resort to colliding particles to observe. For that we have a large number of events and statistically significant results, because everything happens fast in the LHC detectors.

The particles after a collision will rapidly decay into other particles. One of decay is the formation of a pair of fotons. What now occurred, the detection of that pair with a statistical significance of five standard deviations (more than expected by scientists who predicted 4.7 standard deviations).

The region where could be the Higgs boson was outlined in 2011. See the peak in the region of 125 GeV in the following figures:

Data (dots), region where could be found the boson (blue, dark yellow and grey). The dots at the right are fluctuations.

Now, take a look at the 2012 results:

Now the combination of the to decays H -> ZZ -> 4I and H -> γγ (2011+2012):

Detector ATLAS

Detector CMS

So, right now I identified a person so far in my sight of view, it seems familiar to me. Now, I have to getting close to be sure that person is what I thought.

More info can be found:

• Artigo do Público (em Português.
• Press release CERN (em Inglês).
• Artigo de LHC-closer (em Espanhol).