After re-emerging from a rather debilitating new years' eve banquet, I feel I can provide my own answers to the second batch of physics questions I proposed a few days ago to the most active readers of this column.

Be sure about one thing: the answers to the three questions have already been given in some form by a few of the readers in the comments thread; I will nonetheless provide my own explanations, and in so doing I might pick a graph or two to illustrate better the essence of the problems. But first, there was a bonus question included in the package, and nobody found the solution to it. Here is the bonus question again:

"What do you get if you put together three sexy red quarks ?"

The answer is
Rather than writing down my new year's resolution, I find it more constructive to look back at the past year and draw some conclusions on it. I have already done some analysis concerning this blog in a recent post; this one is a more personal view of what happened to me in 2009, and you might well consider it not interesting at all for you -but it is my blog, and it belongs here.

So, let me start with my family. In 2009 neither I, nor my wife or my children, had any major health problem. That is for sure an important thing of which I consider myself quite lucky. Heck, I did not even have to run to the emergency room once! (If you have small kids you know this does happen).
No, not a modification of the now classic "Say of the week" series. Rather, a quote from a very famous Physical Review article which is of relevance to a couple of questions I offered here and here this week:
Room for one please!”
Okay, the year is not over just yet, but it is already time for a little accounting of the traffic on this site in the course of the last eight-and-a-half months -that is, since I moved my blog to Scientific Blogging.

For this year's summary I have been inspired in part by Alex Antunes, who decided to pick his least read articles to draw some conclusions about what really does not sell well here. But I have of course also given a close look at what appears to appease your taste, dear readers.
The turnaround of the three physics questions I offered a few days ago, to stimulate your neurons and extract you from the chocolate and alcohol flood caused by the usual string of Christmas parties and dinners, was rather scarce. Despite that, I wish to repeat the offer today, making some adjustments to reach a wider public. The questions I offer here are easier but still not accessible to everybody. However, my plans are that at least the answers I will give in a couple of days will be understandable. Further, anyone can try the bonus question I ask at the bottom of this piece...
Two days ago I offered you three problems in experimental particle physics, of varied complexity. Three readers tried answering the test in the comments thread: a rather underwhelming turnaround, but what did I expect - we are deep in Christmas vacations after all.

I will give below my own answers to the questions, and then comment some of those I received. For ease of reading, I paste here again the three questions.
Scared by the void of Christmas vacations ? Unable to put just a few more feet between your mouth and the candy tray ? Suffocating in the trivialities of the chit-chat with relatives ? I have a solution for you. How about trying to solve a few simple high-energy physics quizzes ?

I offer three questions below, and you are welcome to think any or all of them over today and tomorrow. In two days I will give my answer, explain the underlying physics a bit, and comment your own answers, if you have been capable of typing them despite your skyrocketing glycemic index.
It is over, but it was frantic. Luca, the Ph.D. student who works with me at the analysis of CMS data (the one which has brought us to the approval of a first signal of the phi meson) summarized it best on Tuesday evening, at the party thrown by our big boss Dario. Holding a glass of good wine in his right hand, and a platter of assorted appetizers in the other, he said: "It is a delirium to work with you: your activity profile is a succession of Dirac deltas".
Two days ago, there was a post on backreaction about the naturalness in science, which is considered by many as a fundamental concept. The point of view expressed in the post is quite easy to grasp : naturalness is not a justified argument in any sense (edit : see the comment of the autor below).