Tommaso Dorigo

The boss is in

This afternoon Giovanni, the head of the CDF-Padova group - my boss - arrived from Italy and met us in the CDF trailers, where we have our headquarters - three double-occupancy offices. Giovanni is a friend and a great physicist, and I am always happy to spend some time with him away from home.

He will also be in Corfu' for a few days after three days here, so we'll have more time then... But tonight, we're having dinner with the students!

Top mass workshop

Yesterday I went to the CDF Top Mass Workshop, a one-day meeting at the University of Chicago. Always nice to have a chance to visit that place, the one where Fermi worked in his attempts at the first nuclear pile. I also love Henry Moore's "Atom Piece", the sculpture in front of the High Energy Physics building on Ellis street.

The meeting was very interesting, and it provided me with a few new stimuli and ideas. In my talk I threw in a proposal to check something I have not seen studied in detail yet: if you increase the resolution in the energy measurement of jets (why, with the Hyperball algorithm of course!) by 30% (the value I am getting from my tests), by how much would your measurement of the top mass increase its precision ?

The question is a meaningful one to answer, and I was positively impressed by Florencia, my ex co-convener of the Jet Energy and Resolution WG and a brilliant physicist, who took my advice and produced an estimate in 20 minutes after my talk, working with her laptop!

So it looks we do gain a lot by improving the RESOLUTION, and not just the SCALE, of the energy measurement of jets. We will pursue this.

Back to the US

Here I am, packing for a new trip which will bring me to Fermilab for a week, and then to Corfù, a nice island in Greece, for a conference. I am tired! There are a lot of things happening in my life presently - among which, the move from old to new house about to begin!- and I need some rest, but unfortunately I have to run around.

Tomorrow, after the usual trip through Munich, I will have to put the finishing touches to my talk for the Top Mass Workshop in Chicago, where I will be able to show some nice new results from the Hyperball algorithm...

Today it was a Sunday, a weekend day, and the last day with my family for the next two weeks. However, I had little choice and had to invest the afternoon in finishing analyzing the data coming out of the Hyperball program and put it into a powerpoint talk.

I need a break!

Eating habits of the overweight physicist

Well.... as the five most faithful readers of this blog probably remember, I am constantly fighting against being overweight, and - having decided I am by now a middle-aged person - I take good care of keeping in a reasonable fit shape, at least for the risks of heart failure connected with excessive body fat. (It also weighs in appreciably my hidden attempts at keeping my physical appearance reasonably attractive - I have a past history of - perceived or real - insufficient appreciation by the female world, so I am very sensitive to its judgement, and I try to make things easier to them).

Now, after coming back from two happy weeks at Fermilab, in the extremely good company of my summer students - Mia and Elena - I discovered my weight had soared to 76 kilograms, from the statutory allowed range of 70 to 73.  I therefore embarked once again (it's been a roller coaster in the last three years, after a huge diet - I posted the plot here in January and then again in June) in a strict diet. I went to my summer vacation in Padola with a clear mind about avoidiing Salsicce and Polenta, Strong Red Wines, Strudel, and other delicacies one usually finds trekking through the refuges in the Dolomites.

It did work, and I am now down to 73.1 kilograms, a success! 2 clear kilograms lost in 20 days, the perfect recipe I myself decided when planning on my first diet: a 1200 calories diet, which saves about 900 calories a day, therefore losing 0.1 kg per day.

Today, though, I was for some reason in a pensive mood (Coleridge used this once, will you tell me where ? It's a poem about a particular flower). I decided to buy a rather outrageously expensive bottle of Pinot Grigio, and I just made the best of it. (Well, some of it is still there for tomorrow evening).

Now, with a apparently clearest mind, but - I know it - actually confused train of thoughts - I am posting this. One day in a week you are allowed to break your diet, whatever that entails. It is a minor overload: even if you were to make 3000 calories, it would weight for 150 calories on all other days, or roughly a tenth of what you are normally losing with the Dorigo regime.

Curious about details ? I start in the morning with coffee and 200 calories - a croissant with marmalade, or some other sugary stuff.  Nothing until lunch, when I concede myself 250 more calories, typically carbohydrates - crackers or bread or something alike, 40 to 50 grams. Lots of water. In the afternoon, one or more coffees are ok. Dinner at 7, carbohydrates again, not much proteins, and lots of vegetables. Water, or diet coke. In total, 700 to 800 calories are ok.  The grand total is always smaller than 1300.

Does it work ? Yes!, if you are strict about it. I found that a huge boost in my motivation was to check my weight every day, plotting the results on a excel spreadsheet. Try it! Being fit is something you owe to yourself, to your relatives, and to your ego.

Is it cool to work this way ?

On Monday I will be leaving for the US again, where - at the University of Chicago - there is a workshop where I have to give a talk on the use of Z->bb decays for the reduction of b-jet Energy scale systematics for the top mass measurement in CDF.

On the Tuesday of the following week, I will then be in Corfù, Greece, at a conference, where I have been invited to give a review talk on high-Pt Physics. This is a long talk, more like a seminar, and I will be talking for ninety minutes!

So, you'd think I'm giving the final touches to the talk slides of both talks at this point. Change color to this sentence, highlight that, put an arrow to show what plot I'm referring to in that sentence. Nope.

I have not started to put together the slides of the first talk yet. And, for the 90' seminar, I have only a vague idea of what I am going to say, and a seminar I gave in march from which to steal material, which however has to be at the very least reinforced, integrated with new results, etcetera.

Is that cool ? I mean, shrugging shoulders in front of the approaching danger, and keeping a cool head, not worrying about deadlines approaching which cannot be sidestepped ?

I once thought it was cool, when I was a student and I saw this being done by others, while I was usually... well, not terrified, but a bit scared every time I had to give a talk about something somewhere.

No, I don't think it's cool. I think it is a bit of a lack of respect to the people that gave you the occasion to present your work, or give an overview of anything. It does not matter how much you think you are good, and how fast you think you are in preparing your slides, and how smart you think you are, you moron. Get your ass on a chair and start doing your homework, damnit!

Up for Result of the Week

In the next issue of Fermilab Today, a measurement I co-authored is going to be reported as "Result of the Week". What our group measured is the cross section for producing top quark pairs, studied by identifying their decay to six jets of hadrons - three from each top quark.

The final state with only hadronic jets is very hard to spot, being submerged by a huge background of generic QCD processes which has a rate three orders of magnitude higher. However, by carefully selecting top-like events and identifying jets coming from b quarks (the golden signature of heavy flavor production) it is possible to enhance the S/N ratio up to about 1 to a few, and then seek an excess of events with the required characteristics. The excess can then be converted numerically to a cross section measurement.

The analysis was the first I was involved in, back in 1992, when I joined the CDF experiment. The top quark was not known yet, and the search in the six-jet mode was deemed desperate - when even the golden channels of lepton plus jets and dileptons were having a hard time finding any evidence. But we persisted, and in 1997 published a PRL named "First observation of the all-hadronic decay of ttbar pairs". Now, with three times more statistics, our group - that is, what is left of the original one, plus new additions - has produced a better measurement. Not a big deal, but still an interesting result - worth getting out on Fermilab Today, to be sure.

Here is the picture we took today, in front of the Physics Department in Padova, and with the background of a monument commemorating Galileo Galilei, the first true scientist in the currently accepted meaning of the word.

Home again

I like to be here when I can...

I'm actually already back into standard family business management mode. A little surprise: my internet provider just upgraded the line to 4.8 Mb/s, from 1.2 Mb/s. How much will the x4 enhancement cost, I still don't know - and prefer to avoid asking.

My plan for the next few days: making a gant diagram of the last things to do before we move into the new house, buy a few books I have to start studying, put order into the work of my summer students (they're at FNAL, but internet allows me to control them from here!), and taking care of a few other errands. I just managed to move my departure from Venice to Chicago from the 30th to the 29th, such that I will be able to follow all the Top mass meeting in CHicago on the 30th. Duh, I just remembered I have to let the organizers know they need not rearrange all the schedule to fit my talk in the late afternoon: I will be there from the start! I'm off to do that now.

Holidays over

Tomorrow I will get back to Venice from Padola, where I am on holidays with my family. The weather has been so bad in the last few days that we've decided to call it off... In the mountains, if it's raining all day there's not really much you can do to have fun with small children, and besides, work is piling up as I speak, so I've better go back to it than waiting for a ray of sunshine here.

Among the things awaiting for me, in random order:

• oversight of the remodeling of my new house, which is in an advanced state (among the things implied is choosing colors for the paint, handles for the doors, buying new furniture, and the like - not unpleasant tasks if you have the time to do it, but...)
• organizing for the move from the old house to the new one - will happen some time late September (main task: packing in an orderly fashion a ton and a half of books and carefully wrap in cotton and bubble wrap some six hundred pounds of rocks and minerals from my beloved collection)
• preparing for a summary talk on high-Pt physics in Corfu', where I am due on September 5th (have not even started thinking about that yet...)
• preparing a talk for the Top Mass Workshop which will be held at the University of Chicago on August 30th (needless to say, will have time to put together the slides on the evening of the 29th)
• Getting back at the helm of our Jet Energy and Resolution group, and organizing a mini-workshop for September (fortunately, in my absence Ken Hatakeyama, my co-leader, has been rock-steady at the helm himself)
• Produce the first meaningful test of the hyperball algorithm on the Z->bb dataset, showing that b-specific jet energy corrections do correct the energy of jets, doh
• start preparing for three exams I am due to give in the fall - they will be instrumental in providing me tenureship, which is not for granted

I think I've forgotten something, but it will come back to me... Ah, in the meantime, I've started a diet again, and my calories regime has been down to 1200 calories/day in the last ten days. I'll have to keep going for one more month to reach my goal of 71 kgs by the end of September. Add that to the fact that moving is recognized as the biggest sources of stress after the loss of a relative, and you may well imagine I am a bit worried about these coming months...

I had a dream

Yesterday I had a dream. I was at a bookstore, where some celebration was ongoing - it had to do with my experiment, CDF. The receptionist was Mario Martinez, a brilliant collaborator from Barcelona. As I entered the bookstore, I found an advertisement of quantum diaries, which was being expanded by adding several appealing names of the show biz plus a few sports champions. In the new glittering list of names a few of the old quantum diarists was missing - among the missing names, mine. (Gordon's name was still on of course!)

I was embitttered by the discovery, and, as I ran into our editor, Chelsea Wald, also attending the celebration, and queueing along with me for entrance in the hall where the party was held, questioned her about why I had not been notified beforehand - the only real reproach I could offer. A discussion followed, when I acknowledged I had posted very little in the past two months, but argued that it was not fair to just kick me out without a warning. Then I actually started attacking my editor with nasty questions, claiming that too little had been done to keep the interest of readers up, and that - left to ourselves - many of the bloggers had lost interest in the enterprise. Now, evidently in this dream the most veritable thing was my ability to be nasty when I argue, because Chelsea ran away with tears in her eyes... Sorry, Chelsea, did not mean to be that bad!

So, I woke up and started pondering on the dream I had just had. I evidently feel guilty for having posted little during the summer. In the dream, though, I was also expressing some concerns that I haven't actually been able to discuss with anybody in the real world... How much outreach are we really doing with these blogs ? Of all comments I received to my posts, if you take out those of friends and those of scientists, not much is left. Sure, comments are not a fair mirror of the audience our posts gain. But, in the absence of any other input, I can't help thinking that, being left in the dark as of how much what we're doing here is useful, it is a unavoidable consequence that our enthusiasm in this enterprise is deemed to fade - at least, mine.

I really think that publicizing the work we do in particle physics is not only useful, but should be conceived as a real part of our job. After all, the youngsters of today, who may or may not be exposed to high energy physics, will be the congressmen of tomorrow, who might just end up voting off the super-duper-cyclotron and funding basic research on skin rejuvenating creams instead. Chelsea, any input ? We need a motivation injection here! :)

Packing work in the holidays suitcase

This morning I'm leaving to Padola (shown in its winter look on the left). This will be 12 days in the mountains, before I go back to Fermilab. But I plan to spend them fruitfully: if the weather is inclement, or if my jetlag keeps me awake, I will have something to do!

First, I've downloaded on my laptop a very interesting paper on heavy quark physics, which I intend to read. It's thick, so I doubt I'm going to be able to read it back to back, should even rain every single day. But I've also downloaded all the stuff I need to keep updating the hyperballs algorithm. Several details still need to be polished, but I think that by the time I'm back to Fermilab I can distribute a new version of the code - the thing has raised a lot of interest lately.