Particle physicists call "jet" the combined effect of many particles produced together when an energetic quark or gluon is kicked out of the hadron it called home, or when it is produced out of the blue by the decay of a massive particle.
The clearest example of the first process are the collisions we routinely produce at the Large Hadron Collider, where pairs of protons traveling at close to the speed of light bang into each other head-on. Protons are like bags of garbage: they contain a complex mix of quarks and gluons. So what happens in the collision is that one individual quark or gluon inside one proton hits a corresponding constituent in the other proton; the two pointlike objects scatter off each other, and get ejected out of the proton containing them.
I am reading a fun paper today, while traveling back home. I spent the past three days at CERN to follow a workshop on machine learning, where I also presented the Anomaly Detection algorithm I have been working on in the past few weeks (and about which I blogged here
). This evening, I needed a work assignment to make my travel time productive, so why not reading some cool new research and blog about it?
I have always been fascinated by optical instruments that provide magnified views of Nature: microscopes, binoculars, telescopes. As a child I badly wanted to watch the Moon, planets, and stars, and see as much detail as I could on all possible targets; at the same time, I avidly used a toy microscope to watch the microworld. So it is not a surprise to find out I have grown up into a particle physicist - I worked hard to put myself in a vantage position from where I can study the smallest building blocks of matter with the most powerful microscope ever constructed, the Large Hadron Collider (LHC).
Last night I was absolutely mesmerized by observing the transit of Ganymede and Io, two of Jupiter's largest four moons, on Jupiter's disk. Along with them, their respective ink-black shadows slowly crossed the illuminated disk of the gas giant. The show lasted a few hours, and by observing it through a telescope I could see a three-dimensional view of the bodies, and appreciate the dynamics of that miniature planetary system.
In this post I wish to explain to you, dear reader, just why the whole thing is so fascinating and fantabulous to see, in the hope that, should you have a chance to observe it yourself, you grab the occasion without considering the lack of sleep it entails. I am sure you will thank me later.
I know, the title of this article will not have you jump on your chair. Most probably, if you are reading these lines you are either terribly bored and in search of anything that can shake you from that state - but let me assure you that will not happen - or you are a freaking enthusiast of heavy flavour physics. In the latter case, you also probably do not need to read further. So why am I writing on anyway? Because I think physics is phun, and rare decays of heavy flavoured hadrons are interesting in their own right.
And there it starts. At a very important juncture for fundamental science, physicists are gathering in Granada this week
as part of a multi-pronged program that will lead to agreeing on what are the priorities for particle physics in Europe.
Given that particle physics is a global, collaborative endeavour nowadays, with experiments typically composed by thousands of physicists from all around the world, we can be sure that what will be agreed is going to shape the future years of this experimental discipline, as not only European projects are discussed, but more in general all projects to which European scientists contribute.