Guess the Plot

I used to post on this blog very abstruse graphs from time to time, asking readers to guess what...

Fun With A Dobson

It is galaxy season in the northern hemisphere, with Ursa Mayor at the zenith during the night...

The Season Of Muons

Particle physics is so cool - you get to build huge detectors with a specific goal clearly stated...

Instead Of An April's Fool

Taking inspiration from Resonaances, who this year offers much more than an April's Fool in his...

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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 »

I am quite happy to report today that the CMS experiment at the CERN Large Hadron Collider has just published a new search which fills a gap in studies of extended Higgs boson sectors. It is a search for the decay of the A boson into Zh pairs, where the Z in turn decays to an electron-positron or a muon-antimuon pair, and the h is assumed to be the 125 GeV Higgs and is sought for in its decay to b-quark pairs. 

If you are short of time, this is the bottomline: no A boson is found in Run 1 CMS data, and limits are set in the parameter space of the relevant theories. But if you have a bit more time to spend here, let's start with the beginning - What's the A boson, you might wonder for a start. 
I am using my blog to advertise the opening of PhD positions in Padova University, to work at several research projects and obtain a PhD in Physics. These are offered to Chinese students through the China Scolarship Council. More information is available at this link.
If you are a bright Chinese student who speaks at least some English and is willing to spend three years working in data analysis for Higgs physics in the CMS experiment, I will take you - so what are you waiting for ? Applications close soon!

Below is a table with deadlines and information.
This one is definitely too juicy to ignore - I need to join the crowd of bystanders-in-awe. 
As you may have heard, ESA's ROSETTA spacecraft successfully landed yesterday on the solid nucleus of comet 67/P, Churyumov-Gerasimenko - a 2.5 mile long conglomerate of rock and ice. I refrain from giving detail of that enormous achievement for humankind, because I rather want to comment on this rather funny twist of the whole story. But still let's first enjoy at least one nice picture of the surface of that distant solar system body...

Forget the Higgs Boson, the Landing on Comets, Missions to Mars, the Genome Project, Nanostructures and all that. This start of this new millennium looks like the dark ages to me if I have to gauge it from discussions I overhear in public places. 
Just... WOW. I did not expect this to happen in my lifetime (and no, I do not expect to die tomorrow either). The Atacama Large Millimeter Array in Chile has pictured a forming planetary system in a young star surrounded by a complex nebula of hot gas.I still remember the Scientific American article I read some 25 years ago about planet formation simulations, which showed how computer models of planetesimals rotating in a cloud of gas around a star. The planetesimals would pick up matter around as they swept the orbital plane, and in the matter of millions of years acquire a planetary mass and "clean up" the area around. Now we are seeing this before us, in the picture below offered by ALMA.
Results of a new search for single top production and large missing energy have been published by the ATLAS collaboration in a recent preprint. I think it is worthwhile to have a look at the idea behind this new search, as the signature of invisible particles produced in LHC collisions and escaping the detectors is important in many of the current and future investigations of beyond-the-standard-model physics.