Life as a Physicist

I spent last Thursday, Friday, and Saturday at a really great conference in Grenoble. The topic was top physics, and lessons and techniques at the Tevatron and at ATLAS. I wish I could put my finger on what made it great: it was a small group (less than 50 people, I think), and everyone was willing to talk. The first day we ran about 3 hours over, for example (yes, yes, a good 30 minutes of that was my fault). Both Lorenzo and Harrison gave great talks as well as the others. I took some pictures too.

I have pages of notes from the conference (all stored electronically, of course, despite my busted laptop - which is getting worse). Some tidbits (if you don’t care, skip over to the last paragraph - partly to help me remember):

• At the Tevatron we produced about 8 tops per day, and 4 single tops per day. LHC will be one per second, and a single top 1 ever two seconds. This is a game changer - top becomes a calibration sample, for example (b-tagging, JES…). I can’t help but wonder if we haven’t explored all of its possible uses as a calibration sample yet. Heck, data for 9 hours at low luminosity (but full luminosity) will give you a top mass peak that you can see! And it is going to be exciting to measure that cross section at 14 TeV!! And they really are are going to do everything without b-tagging at the start of the run!
• No one yet talks about doing analysis in such a way to make the eventual combination with CMS easy. I really wish we’d start thinking that way from the beginning.
• I had not fully appreciated the history of the D0 JLIP tagging algorithm — it was nice to see it in action as far back as LEP and also (as I’ve seen) in ATLAS. I’m sure it is in CMS as well.
• During my talk I made the sarcastic comment that one shouldn’t measure things twice - because you are bound to get different answers. I really did mean that sarcastically — but people kept mentioning that I mentioned it thought out the rest of the talks. Sheesh.
• There was a big difference between the ALTAS and D0 talks. In general, the D0 talks talked about one method, and then went into all the details and tricks and the general mess than a proton-proton collider causes. The ATLAS talks were often an overview of techniques. For example, for the Jet Energy Scale ATLAS showed results (but not details) from about 4 different methods. I’m sure this will change when data arrives.
• Harrison made a rather provocative statement fairly early on in the meeting: we spend too much time trying to get the absolute scale of the Jet Energy correct. Instead we should just match the Monte Carlo to the Data and then move on; who cares about the absolute scale. I and others made the obvious point: in order to do the match don’t you end up with the absolute scale. After several goings around (over wine at lunch!), we figured out: he completely agreed that reducing the error on the jet energy was well worth the technique, but he still wonders if we could save time by not developing independent JES for MC and Data.
• I need to start exploring TMVA.
• In general, the D0 analyses are quite sophisticated — using multivariate techniques like decision trees. Most of the ATLAS analyses don’t yet. In fact, there was some scientism from the audience about our use of these techniques. M. Mangano came up to me at one point and asked how we knew that our decision tree analysis had actually seen single top and not something else (MC tests, the Matrix Method also sees it and it isn’t a machine learning, etc.). It sounds to me like this battle isn’t done yet.

There was only one thing I didn’t like about the conference: the agenda page is password protected. Unless you are a member of D0 or ATLAS you aren’t supposed to have the password. The reasoning is as follows: they wanted to have D0 people be able to talk about internal matters — really wanted to know the dirt behind what went wrong and what to try to avoid when working on ATLAS. And the ATLAS folks should talk about anything they wanted to as well - regardless of weather or not it had been approved. It didn’t work out that way: the ATLAS top group reacted saying that they didn’t want preliminary results shown. The result was the page was password protected. This is too bad, and I think, in the end, the password was not required. First of all, ATLAS is only showing Monte Carlo results (though the ATLAS philosophy is different than the D0 one - D0 is quite comfortable with MC results going out without nearly the cross-checks that data results get). Second, as one speaker put it, “new versions of these results will be shown shortly in ATLAS and will improve on these old results” — so the results we were seeing weren’t the preliminary ones in most cases. As for D0, I think all of the D0 speakers got an email from the top group reminding us that only publicly approved plots were allowed to be shown at this conference. Fortunately, it did not limit the discussion and all of us were quite frank in our revealing of faults and other problems. I am in general against external conferences being password protected.

I’m not sure what to say about this picture, other than just to look at it…

Marseille, like many other cities around the world, buys or has businesses sponsor a particular artist to do something with a common object. I’ve seen bulls in Chicago and pigs in Seattle. Marseille is doing cows.

Oh well (from article):

He suggested that both the administration’s program of eavesdropping without warrants and its use of “enhanced” interrogation techniques for terrorism suspects, including waterboarding, might be acceptable under the Constitution even if they went beyond what the law technically allowed. Mr. Mukasey said the president’s authority as commander in chief might  allow him to supersede laws written by Congress.

Should we believe? I read this while trying to not work on the talk I have to give tomorrow.

Mr. Mukasey noted that a 2002 memorandum by Jay Bybee, an assistant attorney general at the time, stating that the president had the power to circumvent the Geneva Conventions as well as laws banning torture, was later disavowed and superseded.

“Would it be a safe characterization of what you’ve just said that you repudiate this memo as not only being contrary to law, but also contrary to the values America stands for?” Mr. Leahy asked.

“I do,” the nominee replied.

“Thank you,” Mr. Leahy said. “Is there such a thing as a commander-in-chief override that would allow the immunization of acts of torture that violate the law?”

“Not that I’m aware of,” Mr. Mukasey said.

On one hand, this is encouraging to hear. On the other hand, he isn’t exactly going against any current practices in the Bush administration — as he noted, they have already decided that memo is wrong. But what about all those other memos that came afterwards that redefined various practices as “not being torture?”

I’ve heard it called the national pass time here in France. Tomorrow there is a major strike — all the trains (at the very least) will be down. This means all the roads will be clogged with cars — or everyone will take the day off. Not sure. But I have to drive to Grenoble for a top physics workshop… We’ll see how that goes!

This post is to commemorate the death of an email address I’ve owned since 1999: gordonwatts@mindspring.com. Sniff! I’ll miss you!

BTW, anyone here who wants to email me can by using my UW email address: gwatts@phys.washington.edu. I really should create a “decent” about me page…

Beat by their own mistakes too, it looks like. Very depressing. The square where I watched it was full of people. And one odd thing here in Marseille: when they lost not everyone left right away. Bars were still selling beer to everyone in the crowd (you can hang out with open bottles here in Marseille), bars were still completely full… Nice to see the town comforting itself like that…

In a few hours France will face off against England in the semi-finals of the World Cup of Rugby. This is the latest issue of Paris Match - I love the headline: “May the force be with you”. The force!? How old is that headline writer? The guy pictured on the front is nick-named “The caveman” apparently. When I was watching last week and he came onto the field several of the women around me indicated he was hot.

The person in the office next to me has a very odd cell phone ring-tone. I finally figured it out today. It drives me a bit batty, because when I hear it I immediately want to get up and do something about it — it is one of those kinds of sounds. I’d never heard much of the ring because it was always answered quickly: I thought it was a cat howling or something like that.

Today the person was out of the office and their cell phone rang — it went on long enough for me to really identify it: it is a baby crying!

Walking out of the lab here in Marseille the other day I tripped. It was pretty embarrassing. Lots of people around. Further, when I tried to pull my foot under me to regain my balance, it got caught on one of those parking divider concrete things you see in large mall parking lots (yes, it was in the middle of the sidewalk). The result was I went sprawling. Knees and hands. Everyone around me asked if I was ok, but I was so stunned I answered in English instead of French.

Amazingly enough no skin was broken, and I didn’t even rip the knees on my jeans (which has happened before). However, after I got home I discovered that during the fall I’d split the seat of my pants wide open! Fortunately, I was sitting down most of the way on the bus and Metro…

But the really bad news came this morning when I opened up my portable to get work done. As you can see, the screen isn’t doing so well any longer. Over 2 years, and this thing has been through the wars - the outside is completely scratched up. I’m not sure how many times I’ve accidentally dropped it. And it has never even noticed. Indeed, even with this fractured screen coating, it is still quite usable (I just have to be careful when I write on the screen).

I guess it is time for a new portable. If only Lenovo would update their X61 with the high-resolution screen - as they have been saying since the beginning of the summer (hmmm. sounds like Free!).