ICHEP Should Be Good! July 31, 2008
Posted by gordonwatts in Conference, D0.6 comments
ICHEP is really getting under way this Sunday — it should be a good conference – with a bunch of interesting results. Some I know about, some I’ve heard rumors about — I’m eager to see what is actually going to make it out there. The only bummer for me is they aren’t using CERN’s agenda system so I can’t just DeepZoom the thing!
Oh — an D0 just passed another milestone in data it has collected — over 4 fb-1 now! The results shown at ICHEP are on the 3 fb-1, however.
Upgrade Skype July 28, 2008
Posted by gordonwatts in Uncategorized.add a comment
A group of us are attempting to rewrite a Monte Carlo study that some internal referee’s had concerns with – as a result I’ve not had much time for anything but that, eating, sleeping, and changing diapers.
I usually don’t put stuff up here about things like Skype (unless in some other context) – but they just came out with a new version both for the Mac and Windows. Get it. The claim is they worked on call quality. Wow. Paula has a Mac, and I’m on Windows. We used to always get echo’s and Paula’s voice sounded pretty much like she was living in a tin can. The new version has totally killed the echo’s and she sounds like she might even be human.
Unfortunately, it would seem that both ends of the conversation have to upgrade to get the full benefits. At any rate, nice job Skype!
300,000 Euro Firework July 24, 2008
Posted by gordonwatts in Marseille.add a comment
I wrote that while my experience at the Marseille fireworks weren’t all that great – the fireworks themselves were. One of the most stunning was when they made the fort at the end of the Vieux Port drip fire. I was only able to get one good picture of it, and that was at the very end. But it was perhaps my all time favorite firework.
Today I read how much it cost. 300,000 euros — 471,000 dollars! Holy cow!!
Bad Karma July 22, 2008
Posted by gordonwatts in Uncategorized.9 comments
Well, I held EVO up the other day as something that wasn’t doing well. And Skype as something that was done right. Of course, today, using the new version of Skype, I’m getting crashes!
It’s my birthday today (22nd). Stop by and leave a comment! I’ve been doing this blogging for over 3.5 years now. Never imagined I’d still be writing!
Update: Awesome. More bad karma. In the last 15 minutes I’ve gotten 1050 new emails. All of them Russian, all of them bounces. How nice, and right for my birthday! Thaaaank you! 
Now, the question is — how much real email am I going to accidentally throw out with this junk!? And can I use this as an excuse to not do some task (sorry, didn’t see that email!).
Bastille Day: Marseille could do a lot better July 18, 2008
Posted by gordonwatts in Marseille.4 comments
France, of course, doesn’t have July 4th. But they have something very similar — Bastille day. The is the anniversary of the storming of the Bastille prison – which is seen as the start of modern France. So, a lot like July 4th for us back in the USA. Celebration is similar: by afternoon all the stores are closed, BBQ, and lots of fireworks.
Marseille, being the second largest city in France, is no exception. The close off the Old Port to cars and it just gets mobbed with people. Families, kids, you name it – they are there. It is a big party. Except, this time it wasn’t so family friendly. Actually, it wasn’t friendly at all!
First, technical difficulties prevented the 10pm start of the fireworks. They finally went off at midnight, after a good fraction of people had given up. Fortunately, by that time, Paula and our kid had gone home to bed. They managed to catch the fireworks over the tops of buildings.
Second, groups of kids set off fireworks. These aren’t small fireworks. Big ones. Ones that will do damage to your feet if they are near. This effectively cleared out certain sections of the street down on the Old Port. This was ok – you could spot these sections and avoid them if you wanted to. What was not ok was every now and then they would lob one of these large fireworks into the crowd that was patiently waiting for the real fireworks to start!
Third, when the fireworks finally started, everyone turned to concentrate on them rather than the explosions from the kids behind us. The kids then banded together — about 50 of them — in a scrum, and charged the crowd. Their aim was to push us into the water: we were standing on the edge of the dock. The dock is only about 8 inches above the water, so this is no big deal as long as you can swim. But the kids (some small)? And people were sitting down enjoying themselves when this scrum comes trampling in? And they were harsh. The second time they charged the crowd people got fed up and fought back. It wasn’t pretty, but they left us alone after that. Where the #*#^^@^^#@ were the police? There wasn’t one to be seen anywhere at that point. It was crowd justice, pure and simple. This is not the way a real city behaves – certainly not the second largest one in all of France.
I feel bad writing that. This town’s reputation is worse than the reality. Heck, I love this town. We will most likely return next year if we can swing the money situation too. So I feel a little like I’m betraying the town. But still, I was pretty mad.
The fireworks, on the other hand, were amazing. They had a row of barges up and down the middle of the water in the port, and they shot fireworks off them, racing up and down the line. Very cool. And the old fort dripping with fire was incredible – one of the most fantastic displays I’ve ever seen. I had only a hand-held camera, but I did what I could.
Goes Bang! in the Night July 18, 2008
Posted by gordonwatts in Marseille.2 comments
See those shutters that are half open in the picture I took from our bedroom window here in Marseille? Those things are loud! Here in Marseille, when the Mistral blows, only things that are bolted down stay in one place. This includes things like shutters. And when the wind grabs a hold of them they make a horrible racket. Here in downtown Marseille you can hear the noise from them hitting the walls all night long – crack! bang! Makes it hard to sleep!
Basic Physics in ATLAS July 17, 2008
Posted by gordonwatts in ATLAS, physics.4 comments
There are times when I worry that things I have taught in introductory physics – like electricity and magnetism – aren’t really used in particle physics (At UW these are called Physics 121, 122, and 123).
The biggest example is momentum conservation. We use this all the time. In fact, one of the primary ways we will discover a new beyond-the-standard-model particle is via momentum conservation. A common line of reasoning is that we’ve not been able to detect this particle up to now because it doesn’t interact with our matter and our detectors as we expect it to. This is where basic physics comes to the rescue. We know the initial momentum of the collision in our detector. If this new particle were to fly off into the distance and not interact with our detector, then when we summed up the momentum of all of the outgoing particles… well, there would be some missing momentum! Score! Of course, it isn’t quite that simple, things like neutrinos will mimic exactly that signal, but there are ways around it.
The second place basic physics often comes into play is in detector construction and operation. For example, ATLAS has two large and very powerful magnetic fields. The first is the inner tracking field, and the second is the outer toroid field. Magnetic fields interact – think of bringing together two North pole magnets. So these two fields were carefully designed not to interact.
Except, one has to pump current through the outer toroid field to the inner solenoid magnet. As anyone who has taken a basic E&M course will tell you, a current generates a magnetic field. This means the cables that carry the current have to be able to withstand the force of the magnetic field interaction! At these field strengths and the 1000’s of amps of current flowing – that is a lot.
Of course, the engineers knew about this, and designed the cable housing to withstand this. Trickier than it sounds since all of this is superconducting. Still, it was nice to hear the reported successful test of this.
In the picture the 8 large tubes that surround the ATLAS detector generate the toroid field – they are 8 really giant superconducting magnets.
The ATLAS Book July 16, 2008
Posted by gordonwatts in ATLAS, life.1 comment so far
I learned about the ATLAS book at the Overview week. This is a coffee table book — looks stunning. There are sample chapters. Check it out. I think it will hit bookstores sometime near the end of the summer. I hope they will make it available at Amazon and similar places.
ATLAS Week July 15, 2008
Posted by gordonwatts in ATLAS, physics life.add a comment
Last week was the big once-a-year ATLAS Overview Week. ATLAS holds several collaboration meetings each year. The Overview week is a one week retreat — far enough from CERN that everyone can talk and discuss and isn’t constantly distracted by work. A retreat, of sorts. Many other collaborations do this – both CDF and D0, for example. I’m conflicted about the ATLAS version of these meetings.
First off, this one was better than the last. That isn’t to take anything away from the last one in Glasgow – which was well organized and had a lot of good talks and discussions. This one, in Bern, takes place about two months before we are expecting data, however. I think that gave it a totally different tone. There was much less star gazing — grand plans of the discoveries we would make when the LHC first turned on. That said… the week was organized to approximately follow the flow of the data, from the LHC, to the various sub-detectors, to the trigger, to basic object identification, and, finally, to physics.
The beginning of the week was fascinating. Almost all detector groups now have real data to play with in the form of cosmic rays. They have real problems. They are starting to measure actual numbers of dead channels. They are spending their time getting every channel and readout board working. Those talks had a good dose of realism. I particularly remember, in response to a question, the head of the trigger commenting that the first thing to do was get the most basic stupidest trigger working: a bunch crossing trigger. None of this fancy electron or muon identification. Just the most basic thing so that everyone else could start to see triggers – then everyone can work in parallel. Very cool.
As we got further and further away from the detector and cosmic ray data, the talks were not as compelling. This isn’t a criticism, it is just they don’t have real data to play with. The b-tagging work that I am participating in, for example, needs a collection of jets with tracks to make it real. That means that a trigger, a calorimeter, and a tracker have to work. That means the tracking software has to work, the jet reconstruction software has to work. While all of that has been testing in bits and some of it has been tested with Monte Carlo… well, nothing replaces real data. I can’t wait.
But those first few days where you could hear the panic of “data! We have to make this work now!” setting in definitely made the talks in this meeting well worth it. Which brings me to my main beef with this conference. I think this is one of the most expensive conferences I’ve ever attended – and it is an internal meeting. I understand why it was expensive – we are a large group and it is hard to find a cheap venue that will hold us and this is Switzerland, which is just expensive no matter how you look at it; doubly so for someone in the USA due to the exchange rate. The upshot is that many people who I think wanted to attend could not because their groups could not afford it. I noticed this with both European and US groups. This is too bad. More than one person explained that this was historical – Overview weeks were aimed to give an overview of the current status of the experiment – so just the big guys would attend.
I really like the idea that these meetings occur away from CERN. I hope that we in ATLAS can adapt them to become workshops which include postdocs and students – indeed, are more aimed at them then they are at old people like myself.
The other half of this meeting was that I had internet access between 8am and 6pm, and that was it. I found myself going out at night, always coming home a bit drunk, but up at 7am and sitting in the meeting room by 8 or 8:30 (except, ahem, for Friday). I got more done there than I have in a long time and I still managed to listen to most of the talks. Even got to bed at a more reasonable hour. Suddenly no Internet at home is starting to sound reasonable! Despite the horrible train ride home, I returned refreshed. That almost is never the case for me and a conference. I usually am more stressed out because I’ve fallen so far behind on work.
EVO SUCKS July 14, 2008
Posted by gordonwatts in university.20 comments
This post should be titled “Congratulations to John!” and all I should be saying in it is “John passed his General exam! This is the second of three exams you have to pass in order to get your Ph.D. at UW. Now it is on to the Higgs hunt at D0!” or something similar.
Instead I got so angry at his General exam that I was writing 4 letter words all across my copy of his slides.
No fault of his. It was EVO’s fault. EVO is a multi-point video conferencing system. That is, a bunch of people can join and we can all send and receive each other’s video. There were going to be three or four of us watching John’s general exam remotely, and this was the option we settled on. It is, after all, the video conferencing system that is being pushed the hardest for ATLAS.
What a train wreck. What a @*&#&@ disaster. First of all, it kept cutting out. After some undetermined period of time the data stream would drop, video would freeze, and then go away. And the sound would drop. It wouldn’t auto-reconnect. And I couldn’t just end the meeting – I had to restart the whole EVO app. And each time you restart this java-based app, it seems to go and redownload everything from the net. What the heck? Right when you need it to be fast!
Then there was the 20 minutes or so when I was trying to get John to talk a little faster and he couldn’t hear me. Actually, no one at that end could hear me. Finally, using Skype’s instant messaging I was able to get the operator at the other end to reset the connection. Then it worked again.
And during the closed session part of the exam the operator had to leave the room. Not 5 minutes after he left the connection at UW dropped. I had to call up various phones in the department until I found someone that would run up to the 5th floor and notify the guy that he needed to get back in the room (thanks Ivy!). By that time it was just me – so we just used Skype, which worked without flaw for the test of the talk.
EVO has a nice looking snazzy interface. It looks like the authors spent a bunch of time on the interface. I wish they had invested that kind of time in the actual infrastructure and making the conference work1 I could care less about the interface. And ATLAS really wants to make this the official version of video conferencing? EVO doesn’t even have built in echo-canceling – something pretty much everyone else does.
My normal video conferencing solution is ESNET’s ad-hoc system. You usually have to pay for a client (a dedicated room machine runs a bit under $2K). Linux has a free client, and Polycom sells a $99 Windows client. The Linux client is noticeably lower quality, but works well enough. The others are fantastic. And it “just works”. However, according to ALTAS policy using it is not “open” — because the dial-up number is in the USA, not at CERN. So that is out for a future solution, apparently. Skype is out too — as soon as you do a call with more than 2 people you loose the ability to video conference. What else is out there that is cross platform?
I HATE EVO. What a disaster. I was doing John’s General this way because I was trying to save the $7K or so it would have cost myself and another committee member to fly back in the height of summer vacation travel. But not I’m not so sure $7K wouldn’t have been worth it for that 2.5 hour meeting. What a mess.
N.B. Yes, this is my second b**ch post in a row. Don’t know what is getting into me.
