The "new" section of experimental physics papers in the arxiv today features a preprint by the CDF collaboration, titled "First Observation of Vector Boson Pairs in a Hadronic Final State at the Tevatron Collider". This is another instance of a difficult analysis where the CDF and DZERO experiments have competed in the past, and one which is relevant for Higgs boson searches. And CDF got there first once again.

I will describe in detail the analysis and the results later today, because this particular study is dear to me for at least three different reasons:
  1. I have always worked at the search for hadronic resonances in hadron collider data -from the 6-jet decay mode of top pairs (authored the paper in 1997), to the observation of Z boson decays to b-quark jet pairs (my PhD thesis in 1998), to other results along this line.
  2. With a PhD, Giorgio Cortiana, in 2005 we demonstrated a technique to extract electroweak signals in jet data without relying on the presence of charged leptons, but only using the signal of neutrinos. This is at the basis of the result coming out today, and it makes me very happy.
  3. I was the chair of the internal review committee that worked side by side with the authors to get this important new result out in a timely fashion, so I feel this result is also mine, to some extent.
There is a lot to say, and I will say it later today. For now, let me just flash the dijet mass distribution below - a plot on which we will spend a few minutes in the article I am preparing.

The signal has a significance of more than five standard deviations over the background-only hypothesis, and so it is a first observation in its own right. Come back later for details!