Fake Banner
Holiday Chess Riddle

During Christmas holidays I tend to indulge in online chess playing a bit too much, wasting several...

Why Measure The Top Quark Production Cross Section?

As part of my self-celebrations for XX years of blogging activities, I am reposting here (very)...

The Buried Lottery

As part of my self-celebrations for having survived 20 years of blogging (the anniversary was a...

Twenty Years Blogging

Twenty years ago today I got access for the first time to the interface that allowed me to publish...

User picture.
picture for Hank Campbellpicture for Heidi Hendersonpicture for Bente Lilja Byepicture for Sascha Vongehrpicture for Patrick Lockerbypicture for Johannes Koelman
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 »

Blogroll
"A blind use of tail-area probabilities allows the statistician  to cheat, by claiming at a suitable point in a sequential  experiment that he has a train to catch. This must have been known to Khintchine when he proved in 1924 that, in sequential binomial sampling, a "sigmage" of nearly sqrt(2 log(log n)) is reached infinitely often, with probability 1. (Weaker results had been proved earlier by other mathematicians.) But note that the iterated logarithm increases with fabulous slowness, so that this particular objection to the use of tail-area probabilities is theoretical rather than practical.
As a 20-year-long (ok well, 19) member of the CDF collaboration, I am very proud of this wonderful experiments' accomplishments in all areas of high-energy physics, from exotic searches to Higgs searches, from top quark measurements to b-physics measurements, and what not. CDF is a landmark in experimental physics, and the longest-lasting physics experiment ever. But it is not foulproof - nobody is in this wild world of statistical flukes and impossible-to-unearth systematic effects.
While experimentalists gathered in Grenoble present the latest results on High-Energy Physics searches and measurements, phenomenologists like Sven Heinemeyer are working 24/7 to update the picture of the breathing space left for Supersymmetry, in the light of the most recent searches.

You of course do not need to be reminded that Supersymmetry is not a theory but a framework, within which a host of possible manifestations of subnuclear physics are configurable based on the value of 120-or-so free parameters. Because of that, if one wants to discuss in detail what are the most likely versions of SUSY left on the table, and what is the value of the most representative and critical theory parameters, one needs more than paper and pencil.
In the last few days I described in some detail (here and here) the six searches for the Standard Model Higgs boson just produced by CMS, the experiment at the CERN Large Hadron Collider to which I proudly belong.
In my short summary of analyses recently published by CMS, yesterday I left out one which had not yet been released. It is the search for the "golden channel" of Higgs decay, the one which motivated the construction of detectors with large acceptance to energetic leptons: the decay to two Z bosons, with a subsequent decay of the Z's to two charged leptons each.
An orgy of new results has started. Let me just show a few of them concerning Higgs searches in CMS - I am on vacation after all, and I have little time left to comment these interesting new papers and plots after all the sunbathing and restaurants.

Let us start with the Higgs search in the diphoton decay mode by CMS (paper here). With 1.09 inverse femtobarns of data, CMS has a pretty good reach even to this very rare decay mode of the Higgs boson. Let me remind you that only a handful every thousand Higgs particles decay into two photons, in the most favourable circumstances.