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Is The X(5568) A True Resonance ?

The DZERO collaboration published earlier this year a search for resonances decaying to pairs...

The Five Stages Of A Dying Theory

I am told that when a patient is diagnosed with a terminal illness, he or she will likely go through...

Anomaly! Book Presentation At CERN On November 29

The book "Anomaly! Collider physics and the quest for new phenomena at Fermilab" is about to be...

Vector Boson Scattering: ATLAS Tests SM Unitarity

A new paper by the ATLAS collaboration at the CERN Large Hadron Collider produces results in good...

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Tommaso DorigoRSS Feed of this column.

I am an experimental particle physicist working with the CMS experiment at CERN. In my spare time I play chess, abuse the piano, and aim my dobson telescope at faint galaxies.... Read More »

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A picture is worth a thousand words. This is true both for photographs and for graphs, but sometimes the words are spoken to the wrong ears. I would like to offer you a very simple, visual test today: show you a picture and let you guess what it represents. Depending on the response, this might end in oblivion or be tried again with another subject.

So the question is: what does the picture below represent ?



A few hints:

- I did the graph myself, and it took me 10' of programming and a tenth of a second of CPU on my laptop.
A casual look at the Arxiv hep-ph listings this morning was enough to confirm that the feeding frenzy of theoreticians around the latest bait thrown in the waters by CDF is not showing any sign of slowing down.

The paper in question is 1104.2893, and it discusses "Weak-triplet, color-octet scalars and the CDF dijet excess". In their model, the authors (B. Dobrescu and G. Krnjaic) argue in favour of an extension of the standard model which includes rthree new coloured particles, two charged and one neutral state.
The Xenon 100 collaboration has finally released the results of their data analysis, and the results are saying that there is no Dark Matter in sight so far. Since we live in an age where time is precious, I think many of you are only interested in the bottomline. I can give it to you straight away, in the form of the plot which summarizes the results.

Xenon 100 finds three events compatible with a dark matter signal, with a background expected from more mundane sources amounting to 1.8+-0.6 events. The limit they extract on the cross section versus mass of the hypothetical particle are shown below by a thick blue curve, which cuts into the flesh of the preferred parameter space of constrained minimal supersymmetric theories (in grey), pushing them farther away.
A short post today, to mention the latest issue of the CMS Times, a online publication with news from the CMS experiment at CERN's Large Hadron Collider. The CMS Times is always informative and a good resource, but I usually forget to check it due to chronic shortage of CMS time in my agenda.
In the comments thread of one of the posts I wrote recently, where I discussed the new tentative signal of a new jet-decaying particle discovered by the CDF collaboration in their data, a reader asked me if hadronic signals of single vector bosons had been seen before by CDF.
In my post about the new CDF signal of a mysterious new resonance decaying to jet pairs, there is an active comments thread. I posted there a graph crafted by Tommaso Tabarelli de Fatis, a CMS collaborator, who picked the CDF data and simulation and scaled the energy scale of the latter up by a few percent, showing that the agreement of simulation and data was better, and that the bump at 145 GeV could be explained away this way. Below you can see the result of scaling the jet energy scale up by 4% (the jet energy scale is bumped up by just scaling the dijet mass; this is in principle approximate, but it is a good one at that).