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CERN: Are we there yet on the search for the Higgs boson?

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Rumors about imminent results on the Higgs's boson from the LHC experiments are appearing in blogs, social media and newspapers all over the world. Meanwhile thousands of physicists are carefully analyzing the data looking not only for the Higgs but for many other new phenomena. First of all, the data had to be collected. The beams are particles and they are colliding. We detect the products of these collisions in the different detectors that form CMS. So it means that since the collisions take place until all the signatures are recorded in a tape. This is the process of data taking. When the collision takes place we need to have a very fast system that decide whether this collision is interesting or not. These data are than to be reconstructed using complex algorithms and the massive computing power of the Grid. The data that we've to collect from detectors is raw data which is just millions of voltage readings from all the different parts of detector at the point we had a collision. What we want in physics analysis is more the recostructed particles so energies and directions of the particles coming out of the collision. So we got from raw data those recostructed data in order to try to reconstruct the particles coming out from collisions. This is what people use to do the final physics analysis for trying to find evidences of the Higgs or this kind of things that use these reconstructed particles. Than come the data analysis where physicist search these events. Looking for gems in a pile of rubble. So physicist analysis is the process of taking the billions events we've recorded and try to look for a pattern, to look through them interesting events, for look unusual events, and to look to pattern like clustering events and mass. In the billions events we've past few thousands quark events, for example. Perhaps just a handful of Higgs candidate Higgs's boson exist. Other processes can accidentally mimic the same signature we look for pattern that might be produced by top-quark or Higgs boson Trying to prove that we all understand all of these and proving also to our collegues within the experiment that we understand all of these. We document it. Discussing it together. Reviewing it. So when confident, we go to a conference, we put out the paper. We full understand the data and go draw a firm conclusions. To give you an example, imagine you take a photo of a rabbit in tall grass. It will be very hard for you to spot this rabbit, immediatly. Now imagine that you take twenty more photos so far just random landscape and you superimpose them on the picture of the rabbit. It'll be even harder for you to spot this rabbit. That's exactly the situation we are in. Because accelerator perform so well that we get many additional collisions between these collision we might find something interesting. If you know that the rabbit is under the tree we basically hide a part of the photo which contains the tree. Now, what you want to do is take about where the rabbit is in the grass, in the tall grass stems. What we are trying to do, not to looking where the rabbit is, is to figure out how to identify these stems. If we can remove the grass from our view basically what we have is just the rabbit. The most difficult thing at the moment, for example, is the time pressure. We got all these wonderful new data from LHC. We got conferences coming up. We need time to analyze the data. We need time to understand what we're doing, to convince ourselves. Balance all these makes time pressure. Time to analyze the data, time to review, time to write. It is probably the most difficult thing. Going in advance when inspire in last years can easily influence the way physicists look at new data. This is why all the interesting data all been hidden in a black box. That are just to be opened now. I don't see what is in this box.. May be a rabbit? May be nothing :)

Video Details

Duration: 4 minutes and 24 seconds
Year: 2012
Country: United States
Language: English
Producer: CERN video productions
Director: CERN video productions
Views: 75
Posted by: liberascienza on Jul 6, 2012

Produced by: CERN video productions
Director: CERN video productions
4:00 min. / 26 June 2012 / © 2012 CERN
Keywords: higgsjuly4, higgs, boson, ichep, atlas, cms, data, analysis, computer

Language: English
Source Medium: DVCproHD PAL

Reference: CERN-MOVIE-2012-066

http://www.youtube.com/watch?v=bYHlwZJ00tU

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