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On The Residual Brightness Of Eclipsed Jovian Moons

While preparing for another evening of observation of Jupiter's atmosphere with my faithful 16" ...

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Summer is coming, and with it some more intense than usual travel for me. I actually started last...

Modeling Issues Or New Physics ? Surprises From Top Quark Kinematics Study

Simulation, noun:1. Imitation or enactment2. The act or process of pretending; feigning.3. An assumption...

MiniBoone Confirms Neutrino Anomaly

Neutrinos, the most mysterious and fascinating of all elementary particles, continue to puzzle...

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Tommaso DorigoRSS Feed of this column.

Tommaso Dorigo is an experimental particle physicist, who works for the INFN at the University of Padova, and collaborates with the CMS experiment at the CERN LHC. He coordinates the European network... Read More »

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The saga of the superluminal neutrinos took a dramatic turn today, with the publication of a very simple yet definitive study by ICARUS, another neutrino experiment at the Gran Sasso Laboratories, who has looked at the neutrinos shot from CERN since 2010.
Higgs boson hunters often catch themselves dreaming of the boson having a mass high enough to give rise to the spectacular decay into two Z bosons, and then four charged leptons in the final state. At a hadron collider -let's talk of the LHC to be specific- such a signature is the only one providing events which, once properly selected, are more likely signal than background.

The situation of observing an event display being able to tell for sure what it represents, among the infinite possibilities and the intrinsic indetermination of quantum processes, is reassuring and gives a physicist a feeling of power. God did not play dice this time: those two are 100% Z bosons, and their combined mass is exactly the one of the Higgs.
I read with interest and some amusement (on the mouse joke) the piece written here by Sascha Vongehr. I find his arguments wrong and decided to answer him in the comments thread of his post, but my answer got a bit too long and I did not want to hijack a nice discussion that was developing there; plus I found out that what I was writing could be suitable for this blog in its own right. So below I explain what I criticize about his arguments.
"We consider the scattering of charged W bosons [...] the sum of all diagrams still diverges as s/Mw^2. Heavy leptons cannot help us, so the only solution is to introduce a scalar particle which cancels these residual divergences [...] Here, h is just the Higgs particle. If we had not previously introduced it to generate the heavy boson masses, we would have been forced to invent it now to guarantee renormalizability [...] Higgs particles have so far eluded experimental searches [...] one might speculate that they do not exist as elementary fields, adn the higgs "particle" we have introduced actually corresponds to a more complex object [...]"

F. Halzen and A.D. Martin, "Quarks and Leptons", J.Wiley&sons 1984, p.344.
Fabrizio Tamburini (left) is an old friend - I have known him since 1976, when we both used to attend the gatherings of the newborn Associazione Astrofili Veneziani, at the Lido of Venice. The love for astronomy had brought us together, but we took different paths in our scientific activities. Fabrizio remained maybe more faithful to his old love for the universe, and is now a well-known and respected astrophysicist, who studies original ideas in the physics of photon propagation and more. I repeatedly invited him to write about his research here, but so far he has not accepted, mainly for lack of time... But I am sure he will soon.
The Draconids (also called Giacobinids) are a meteor shower associated to comet Giacobini-Zinner (see below for a 100-year-old picture of the comet). While most years this shower passes unnoticed to all but few professionals and experts amateurs, yielding only very few meteors in the nights between October 6th and 10th, every once in a while the Draconids do put up a real show, producing hundreds, or even thousands of meteor streaks per hour in clear skies.