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On Rating Universities

In a world where we live hostages of advertisement, where our email addresses and phone numbers...

Goodbye Peter Higgs, And Thanks For The Boson

Peter Higgs passed away yesterday, at the age of 94. The scottish physicist, a winner of the 2013...

Significance Of Counting Experiments With Background Uncertainty

In the course of Statistics for Data Analysis I give every spring to PhD students in Physics I...

The Analogy: A Powerful Instrument For Physics Outreach

About a month ago I was contacted by a colleague who invited me to write a piece on the topic of...

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Tommaso DorigoRSS Feed of this column.

Tommaso Dorigo is an experimental particle physicist, who works for the INFN at the University of Padova, and collaborates with the CMS and the SWGO experiments. He is the president of the Read More »

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The priest of Vigevano's Duomo must have been startled to realize that by far the most faithful presence at mass, ever since the altar was built, is not nonna Pina but a real dinosaur -a glaring testimony of the falsity of catholic-diffused pseudoscience and of the true origin of life on Earth. The red circle in the picture on the right shows the location of the marble slab in the altar.


The CMS experiment has just released a new result which excludes the possibility that quarks have a substructure at energy scales below 4 TeV. The result comes from the analysis of just a handful of inverse picobarns of collision data -2.9 to be precise- and shows excellently just how well suited are the LHC collisions for this business. The limit is extended by over one TeV above the former result of the Tevatron experiments, and some 600 GeV above the results of the ATLAS collaboration, who also recently reported on their search for of quark compositeness in 7 TeV collisions, finding a limit at 3.4 TeV.
Week number one of my course on Subnuclear Gauge Physics is over. I think that in the first five hours of lesson I have given to my students a reasonable picture of the early experimental attempts and theoretical developments aimed at understanding the structure of atomic nuclei and individual nucleons with electron scattering. So I thought I might try and simplify the picture further, to reach a wider audience here. Of course, the topic is not terribly entertaining, unless one understands fully just how important these studies are for fundamental physics even nowadays -despite having started over 60 years back.
Swamped by my course of Subnuclear Gauge Physics, I have little time left to surf the web and keep an eye on what happens in the blogs I usually visit. Nevertheless, today is Saturday and I have allowed myself a short tour. Below is a list of the most interesting things I have read.


  • First of all, there's an interesting new blog out there, with experimental particle physics explained to laymen. The language is not English, but it is a language you should learn, too.
As 2010 nears its end, the Tevatron experiments feel the monopoly of top quark physics being taken from their hands, due to the good news on the running of the Large Hadron Collider. The ATLAS and CMS experiments there have started to mine their datasets, now amounting to over 20 inverse picobarns and growing significantly by the day. These datasets contain as many top quark pairs as half an inverse femtobarn worth of Tevatron collisions, due to the 20-fold higher cross section of top pairs at the LHC.
"Since two fermions cannot turn into three fermions, the experimental observation of three-jet events in e+e- annihilation, first accomplished by the TASSO collaboration in June 1979 and confirmed by the other collaborations at PETRA two months later, implies the discovery of a new particle. Similar to the quarks, this new particle hadronizes into a jet, and therefore cannot be a color singlet. These three-jet events are most naturally explained by a hard noncollinear bremsstrahlung . [...] Thus the 1979 discovery of the second gauge particle, the gluon, occurred more than fifty years after that of the photon. This particle is also the first [...] gauge particle with self-interactions.