## A new particle at Fermilab?

06/04/2011

I am a registered reader at New York Times and subscribed Dennis Overbye‘s articles. So, this morning I received the mail from the journal with a new writing from Dennis. The title is “At Particle Lab, a Tantalizing Glimpse Has Physicists Holding Their Breaths”. I just jumped on my chair and then, eagerly, read the article. Indeed, CDF Collaboration posted a paper on arXiv last night (see here). The kind of process that they studied is the one with a final diboson (WW or WZ) from a lepton plus jets. They analyzed the invariant mass for masses higher than $100\ GeV/c^2$. They get a $3\sigma$ excess in the region $120-160\ GeV/c^2$ that, if confirmed, should correspond to a new particle. Some tests seem  to point toward a non-Standard Model particle having a mass of $150\ GeV/c^2$ that cannot be identified with Higgs.

As always, it is important to emphasize the this is a $3\sigma$ evidence and further analysis is needed to confirm or disprove the discovery. But it is important to emphasize that Tevatron is paving the way to a large number of discoveries to be seen soon at LHC.

Update: CDF will present these results at a seminar. We can follow it on the web here.

Another update: A post by Tommaso Dorigo, one of the authors of the CDF paper, is here.

CDF Collaboration, & T. Aaltonen (2011). Invariant Mass Distribution of Jet Pairs Produced in Association with a
W boson in ppbar Collisions at sqrt(s) = 1.96 TeV arXiv arXiv: 1104.0699v1