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200 Run 2 Papers from DZERO July 29, 2010

Posted by gordonwatts in Uncategorized.

Well, almost. We are at 185 published papers, 4 more accepted, and 7 more submitted. 19 of them have been cited more than 50 times, 5 more than 100, and 2 more than 250. So that makes 196 – so really close.

And this is just Run 2. Another 132 papers were published from Run 1 data. And none of this counts all the preliminary results we’ve put out between the papers, which often require almost as much work.

And the D0 collaboration is about to have its annual workshop – here in Marseille – so it seems like a fitting time to congratulate everyone on this milestone. It is fitting that this comes after a very successful ICHEP conference for the Tevatron experiments and D0.

So, what are those papers cited more than 250 times? One is the DZERO detector upgrade paper. Anytime someone writes about the DZERO detector (including DZERO) they reference this paper. The other one is the Direct limits on the Bs Oscillation Frequency. This paper caused some controversy when it came out as DZERO took a shortcut to beat CDF with this result (indeed, the DZERO detector and DAQ won’t allow it to make as good a measurement at CDF’s). It is good to see a paper like that getting so many citations!

There are of course several I have very fond memories of – like the Observation of Single Top – especially the almost two weeks of sleepless nights caused by Terry Wyatt’s rather innocuous statement during one of the final approval meetings “yeah, you should be able to improve that in an hour or two”.

DZERO has published so many papers that it got me into trouble. When I was up for tenure one thing the College Council required was a complete copy of all the papers I was an author on (the college council is the last group outside the department that reviews your tenure case carefully at UW). This means I had to download the PDF of every single paper from the APS and other journal sites. I then put them together into a giant PDF file. It was more than 2000 pages. I couldn’t print out the required two copies because I was in Europe in the time. So I emailed the PDF file to the department chair’s assistant with the simple text “please print out two copies for my tenure case” and promptly shut off the computer and poured my self a Pastis. Or three. Stitching together 2000 pages of PDF is a lot of work – I deserved it! Turns out that was the easy part.

A few hours later I was ready to crash and I thought I’d check my email to make sure everything was ok. Good news: the 2000+ PDF file didn’t bounce. Bad news was the string of increasingly frantic emails from first the administrative assistant and then from the department chair. They started with “Thanks! Printing now on my desktop printer!” That was a bad sign: that desktop printer is one of those small slow printers that prints out single sided and one sheet at a time – designed to print out one or two page letters so they can be signed and mailed. A few hours (!!) later “I’m at page 200 and it has already jammed a twice. How long is this?” and “I just checked the PDF, this is 2000 pages! You’re crazy!” and then the first email from the department chair that simply said “You might be buying us a new printer” and then “Scratch that, get me a new administrative assistant, I think she is about to quit” and finally to “ok, all done. But you had better send her (and me) a big box of chocolates and flowers.” As you might imagine my heart was beating faster and faster as I read these messages. I collapsed and slept.

It wasn’t over. The next morning there is an email broadcast to the department saying “We are aware that APS has shut off access to all of their journals for everyone at the University of Washington. This is not part of a journal budget cut; we will send more information as soon as we have it.” And then about 30 minutes later another email had been sent “The shut off was due to someone downloading a huge number of papers from UW and, it appears, from inside this department.” Great. I caused the APS to shut off the whole university. I had to get on the phone to someone at APS to explain myself before they would turn access back on.

I should point out that while DZERO got me into trouble there, I should also say that without the amazing success of the experiment I never would have gotten tenure. I’ve been hugely lucky to work with a lot of truly excellent physicists, first from Dave and Rich at Brown who were willing to take a chance on a fresh graduate student from CDF to Henry at UW. And over the course of these 200 papers I’ve been lucky enough to two work with 3 students – Andy, Thomas, and John, and Aran as a postdoc. It is with some pride that I note they are now all either doing better than I am or obviously on their way to doing better than I have.

On a more somber note, I asked Stefan, one of the co-spokes people, to send me a copy of the plaque down in the control room. As far as DZERO’s ability to mark passing time, there are 18 people that have helped this experiment and didn’t live to see the 200’th paper. I’m not going to list all 18 (though I’d be happy to post the plaque if people request it), but I’d like to mention several that I knew myself – Dan Owen (who can forget?!) who worked on the calorimeters and trigger, Andzrej Zieminski who knew my father and did a lot for our b-physics program, Rich Smith who worked so hard on our solenoid (and perhaps the recent dimuon asymmetry paper is in part thanks to!), and Harry Melanson who did a great deal of software and operations work.

I don’t think most of us are here – now or anytime in the past – because this was “just a job.” No one is paid enough to deal with the DZERO software framework – though I should note the LHC ones make ours look like a dream. We are here and contributed to whatever number of those 200 papers because we believe the world must understand the fundamental laws that govern it, because we like solving very difficult problems, we like playing with cool toys (like the DZERO detector), and because we like working with each other. And, on a personal note, it is good to know that I can still break the DAQ system (yes, that 10 GB log file that is forcing resets at 1:30 am and 7:30 am is my fault).

I bet that If you add the Run 1 papers and the Run 2 papers together we will break 400 before we are done!


Rumors July 18, 2010

Posted by gordonwatts in Critical Thinking, Gossip, Higgs, Rumors.
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Who doesn’t love a little gossip every now and then? Tommaso, as is usual for his style, started one the other day – that the Tevatron claims to have seen a light standard model Higgs. For whatever the reasons (both positive and negative) this one caught like wildfire. You know its big when it shows up on this site!

But to make this really work – and I mean really work in that rumors provide some sort of science payback – you need a conversation. Someone has to say the rumor (to start it). Then someone else picks it up and perhaps spreads it. But then people want to join in on the conversation. For example – “there is no way that can be true because of x, y, and z”, and then someone else says “ah – but you forgot that x can be zero, and if that happens then y and z don’t matter, and this becomes possible once more! Ha!” And so on.

That part of the rumor and gossip conversation I do consider useful. For one thing, it makes the gossipers smarter. Assembling the set of critical arguments to work out the possibility that a rumor is true or not often takes some pretty deep knowledge of the field. And from this discussion new ideas can come as well. For example, I learned quite a bit by watching the gossip and speculation after the CDF forward muon results (shoot, I can’t find a link for that result!) and DZERO same sign asymmetric muon results were released.

Which brings me to the real reason I’m writing this result. That conversation. Currently I see it on Facebook. Seriously! In my circle of friends there are a bunch of experimentalists and theorists who get into some pretty serious discussions using nothing more than one or two lines of text – or perhaps a paragraph. It is excellent. Facebook does an excellent job of re-creating the water cooler – a bunch of people standing around. Though it is better – even if you have to be busy in a meeting or teaching a class you can skip out and rejoin the conversation and read up on what everyone said! This style of conversation is also very important for someone like me: who is constantly traveling and can’t always drop by an office to catch up on the latest.

Before Facebook this happened mostly in blog comments. It still does, and the quality is quite high there, but it seems like it moves more slowly. How about twitter? I did a search over there, and there is lots of chat. But the quality level is pretty low – it is mostly people riffing of the idea or pointers to articles, etc. Are there other places people discuss this sort of thing, but at a physics level? Or perhaps better ways to use tools like twitter to find good conversation? Where else do these conversations occur in the modern digital world?

Favorite Higgs joke seen on twitter. 🙂

P.S. It is almost impossible for me to participate in this particular rumor/gossip because I am an active member of DZERO, one of the two Tevatron experiments. No matter what I say, I’m screwed. So, best not to say anything. Sorry if you came to this post expecting something else!

The ICHEP Shuffle July 15, 2010

Posted by gordonwatts in Uncategorized.
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Or maybe it should be called the ICHEP Crunch. We are one week out now. And from an experimentalist at-a-large-collider-experiment’s point-of-view, ICHEP is almost settled. The almost-final versions of all the plots are prepared, the supporting text sanitized of jargon is being fine-tuned, and the large collaborations are getting their last review in of the results. Heck, even some early results are staring to trickle out (CDF has released a two mass Higgs searchs: WH and ZH associated production (no excess!!) and a search for a standard model higgs decaying to taus (find all CDF results here), and DZERO has a search for a t’ quark (find all DZERO results here).

It feels a little bit like the ‘night before Christmas. It is the calm that is so spooky… Which is in direct contrast, of course, to what is going on outside the experiments in the papers and other blogs…

I’m fortunate enough to be on two of the experiments, ATLAS and DZERO, and on each experiment I’m participating in two sides of the shuffle. On DZERO I have a student working on getting one of the results ready. I bet that the “ICHEP deadline” was first talked about almost 6 months ago. That is about the time that the pressure started building for the folks doing the real work in the experiments. Ever since then each time someone wants to add something new, or spend the time to better understand and reduce a systematic error, they have to ask themselves “does this mean not releasing it for ICHEP?”*

In ATLAS I help run one of the groups producing results. This is management, not physics I’m doing there. The goal for people doing this task is to make sure that all the results are high enough quality to enter the review process. Sometimes this means convincing people to drop a plot, or add an extra plot. By the time someone like me gets heavily involved in the day-to-day of the analyses being prepared we are getting very close to the internal review process.

Back on DZERO I’m also helping out with one of the reviews of an analysis. Once the analyzers have put the finishing touches on their analysis, and the people running their physics group give the ok, the analysis is handed off to an internal review group. These people are meant to be independent reviewers of the analysis, and are supposed to go over it with a fine-toothed comb. Unlike external reviewers, they have access to all the internal information of the experiment. The review is based on an “analysis note” and supporting documentation. Just the note can be 100’s of pages long in case of a complex analysis (Like the Higgs searches from CDF I mentioned above). If no problems are found this review probably takes about a week. But a fresh set of eyes always turns up new problems. It is very intense time for the reviewers and the analyzers: the reviewers send questions, and the analyzers respond as fast as they can so that the review doesn’t get stuck and miss ICHEP. BTW, if you watch the experiments you’ll often see one or two or three analyses come out just after ICHEP – these are the ones where an issue was raised and couldn’t be addressed in time to make it for the conference.

Finally, with that done, the ICHEP shuffle enters its last phase: collaboration review. The now perfected analysis along with documentation suitable for everyone to read (which may be a journal paper draft) is thrown up on an internal web page and a message is broadcast to the complete collaboration (all 600 for DZERO or 3000 for ATLAS): “Our experiment is going to release this work – this week is the last chance to raise issues before it is made public!”

At the same time this review is on going everyone is putting together their ICHEP talks, running practice talks to make sure they are high quality, and answering questions that come in from the collaboration. A popular analysis can get 100’s of comments, for example (an unpopular one might get just a few). Each comment must be reviewed and answered by the analyzers and the answers cross-checked by the internal review. At the same time public web pages are being prepared with high quality versions of all the plots and links to the supporting text and documents.

And then ICHEP starts!

So… you might ask… what defines the length of the ICHEP Shuffle? Which is about 6 months? At the two ends of the year there are two large sets of conferences. ICHEP this year is in the summer, and in the winter is the Morriond series. I’ll bet you good money that I’ll see emails with the title “Morriond Analysis Planning” hitting my Inbox the week after ICHEP is over.

But, for us in these large collider experiments, ICHEP is the breather between the dances. A chance to relax, look around, see what everyone else is doing, get some new ideas, and maybe even explore Pairs!

[Cross-posted on the ICHEP blog]