One of the cool things I have learned to do, through years of experience in data analysis at particle colliders, is to visualize the complex kinematics of a signal process in a multi-dimensional space, and imagine ways to separate it from backgrounds by selecting in the hyperspace the signal-rich region. I came across a very simple example of the above rather abstract statement yesterday, and I wish to share it with you.

To help you visualize what I am going to discuss, here is the example: an avocado in a square tumbler. The avocado is top pair production, and the glass is Z plus b-antib production.

... Confused ? Let me explain.

I do not know about you, but top quarks fascinate me. Since my early years as a student in particle physics I participated in the top search, and then the top discovery, with the CDF experiment at the Tevatron collider; and I then worked for many more years with top quark samples. And that particle is fascinating for many different reasons: its phenomenology, the richness of its decays, its mass close to the scale of electroweak symmetry breaking.

I feel honored by having had a chance to study the first few tens of top quark events that physicists have been able to produce, and yet I regret that during the last few years I have been unable to put my hands on the much larger datasets collected by the CDF experiment.

Tomorrow morning Venice will sink under a maximum tide predicted to reach 1.30 meters above average sea level. The event will occur at 8.35AM, a time when Venetian residents are in the streets trying to bring children to school or to reach their workplace. You can see the predicted evolution of the tide in the graph below, where the red curve shows the time variation of the season's average, and the blue one the actual prediction for tomorrow. The peak of 130 cm above average sea level is predicted to occur at 8.35AM -which is 2.35AM in New York, or 5.35PM in Tokyo.