Anomaly! Now Available As E-Book

Today I would like to mention that my book "Anomaly! Collider Physics and the Quest for New Phenomena...

Two Physics Blogs You Should Not Miss

I would like to use this space to advertise a couple of blogs you might be interesting to know...

The Six-Month Cycle Of The Experimental Physicist

Every year, at about this time, the level of activity of physicists working in experimental collaborations...

LHCb Finds Suppressed Lambda_B Decay

The so-called Lambda_b baryon is a well-studied particle nowadays, with several experiments having...

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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 experiment at the CERN LHC. He coordinates the European network... Read More »

A question posed by Tony Smith in the thread of the previous post (which dealt with the choice of the bin width in histograms) triggered me to do a little work to produce a convincing answer to him.

The issue is the following. Tony got interested in a few top candidate events in a few mass distributions published by CDF and DZERO quite some time ago, which seemed to all cluster in the surroundings of 145 GeV. Could those eight candidate events (once summed across the various channels and experiments) be the signal of some resonance different from top quarks ?
I was unaware of the following story, which was brought to my attention by Monica Pepe-Altarelli yesterday. Since I totally agree that nobody should be detained without proof of guilt for long periods of time, and since we are talking of a physicist, I am glad to broadcast the story here.
The presentation of data is a very rich subject, on which there is a whole lot to discuss, even by restricting to the issues relevant to our dear field of experimental high-energy physics. Usually too little thought is given to it, even by expert researchers, so I thought that maybe today I would offer here some ideas on one very basic issue, the one of how to choose the width of the bins of a histogram.
The measurement of the production rate of top quark pairs at the Tevatron is by now a very well developed technology, where it is hard to invent anything new. Eight years ago, however, there was still the chance to develop new techniques and explore new land.
Okay, the riddle I posted two days ago  was indeed solved by theorists - albeit ones with good internet connections and smart search engines.

The figure, pasted below for your convenience, is from the CDF collaboration, and it refers to a "famous" analysis - one of the few important measurements for which Run II at the Tevatron was considered a good idea (thank god that one sold with the funding agencies, because there were sooo many others that eventually paid off!).

In a display of nonchalance that should teach us a thing or two, the ATLAS collaboration has put an end to the Easter Higgs Rumour (EHR), which brought the blogosphere in an excited state for at least a week, and experimentalists and theorists for even more time. They did so by publishing a very narrow-focused document, totaling less than five pages, where they discuss the backgrounds to Higgs boson decays in the diphoton final state.