From The Great Wall To The Great Collider

With a long delay, last week I was finally able to have a look at the book "From the Great Wall...

Top Secret: On Confidentiality On Scientific Issues, Across The Ring And Across The Bedroom

The following text, a short excerpt from the book "Anomaly!", recounts the time when the top quark...

Choose the next topic

Being back in blogging mood, I decided I would make a poll among the most affectionate readers...

A Workshop On Applied Statistics

A Sino-Italian workshop on Applied Statistics was held today at the Department of Statistical Sciences...

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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 »

Top quarks, the heaviest known elementary particles, were discovered in 1995 by the CDF and DZERO collaborations, when the two Fermilab experiments spotted the decay of  top-antitop pairs produced by strong interactions in the proton-antiproton collisions provided by the Tevatron collider at 1.8 TeV center-of-mass energy. 
This week I am in Warsaw, where I attend the XI workshop on particle correlations and femtoscopy. I am actually here to give a seminar on statistical methods in particle physics next Thursday, but of course I am also going to try and deepen my understanding of the field of investigations of heavy ion collisions.

Jan Pluta, one of the old-schoolers of the field, gave an introductory talk this morning. It was titled "A brief history of femtoscopy and particle correlations - a personal view". I am reporting below some impressions from his presentation.

What is femtoscopy ? Jan started by warning that he would indeed only give a personal view of the history of the field, and that the view of others may be very different.
Recurrently, uninformed journalists re-discover the h-index and decide to create their own list of the "top scientists" in their country. The most zealous also draw some summary statistics from the list, and then venture to speculate wildly about it. Alas, it's a pattern I've seen a few times now.

The latest is an article which somebody posted on my Facebook column. It is uninteresting to see what conclusions are drawn from the graphs and lists published there, as the data are quite incomplete - in the h-index-ordered list of Italian researchers I do not appear, for one, but similarly do not dozens of top scientists who have even higher h-indices.

As I am spending my time these days selecting candidates for early-stage researcher positions in the EU network I am coordinating, I am reminded of my own experience as a participant to job interviews from the other side of the table. The text below tells the story of my interviews for a post-doctoral position in 1998. Enjoy! 


A longtime follower of this blog, Tony Smith, pointed out to me today this arxiv paper published three days ago. In it, CMS data from Run 1 of the LHC are used to speculate that there might be a second Higgs boson hiding in the data at a mass of about 145 GeV. Check out the two graphs that they produce.
The first one, shown below, is their own interpretation of the four-lepton invariant mass from CMS data and background in the H-->ZZ--> four lepton final state:

Yesterday my 16 year old son surprised me by explaining that he had been taught at school what alpha, beta, and gamma decays are. He had learned a lot, but I was able to add a little more background information to the picture as he asked me what was the neutrino, which his professor had correctly explained was one of the particles emitted in beta decay.

With hindsight, my surprise probably comes from keeping my brain inactive and sticking to a rather conservative idea of how sciences should be taught at school; that idea is that understanding physics requires you to have some solid basis in maths, and that the explanation of phenomena should proceed along with quantitative calculations.