Kiwi Particle Physicist

April 25, 2006

Field Trip 2

Oops. I was going to upload this yesterday, but I lost the cable to get the photos off the camera. Better late than never. Just thought I’d post a summary of the stuff we saw on the trip.

We left about midday on Friday to go to SPring-8, which is the world’s highest energy synchrotron light source. They have a high-energy beam of electrons, which they steer around a 1.5km storage ring using magnets. Every time they bend the beam it emits a burst of radiation tangent to the ring. Because the radiation is extremely high energy, higher than X-rays for example, it is useful for materials science and life science. For example, they shoot the radiation through crystals and from the way it is absorbed or scattered they can determine their internal structure.

The following photo was taken at the laser reverse Compton scattering experimental hutch, where Nakano claimed to have found the first evidence for the pentaquark Theta in 2002. The results are still controversial, and haven’t been consistently confirmed by other experiments, so they are setting up a new experiment so they can take more data in the near future.

After we finished the tour of SPring-8 we went to Harima Observatory. It’s one of the major Observatories in Japan, hidden in the mountains in the middle of Hyogo prefecture, about an hour’s drive northwest of Kobe. It was supposed to be dark, but the light pollution from Himeji and Okayama was still pretty bad. On the bright side, the weather was clear and we had a good view through the big telescopes as well as just looking at the stars from outside. It’s not normally possible to see more than a handful of stars in Osaka or Tokyo or Tsukuba. Professor Tsunemi took the following shot of Saturn, although it didn’t come out nearly as good as it looked through the scope.

April 22, 2006

Field Trip 1

Absolutely buggered. Just got back to uni from the field trip. The new bachelor’s students had way too much energy, and they were up yapping all night. The other doctor’s course students and I headed off to bed around 4:00, and we were woken at 7:00 for breakfast and then lectures all morning. I took a few photos at SPring-8 and the observatory, which I’ll post tomorrow.

Overall it was good fun. It’s the same trip I did exactly six years ago when I had just started at Osaka, and I can't believe how quickly the time has passed. It felt really odd to be the old guy answering everyone’s questions this time around, as opposed to one of the overenthusiastic new kids. Four years of undergrad should mellow them out a bit.

April 20, 2006

Home Again

Just finished on-call shift this afternoon. I had one 5:00 AM wakeup from the guy on the experimental shift, he thought some of the data was funny, but it was nothing to worry about. Also had a bit of excitement when I got called out to fix a computer that wasn’t responding. Eventually a reboot got it going again, but we lost about 30 minutes of valuable data. Overall it wasn’t too bad, especially for just after a restart.

I’m back in Kyoto at the moment, and leave again tomorrow lunchtime to go on a field trip with uni. Every year in April a handful of professors take the first year bachelor’s students on an overnight field trip to SPring-8 (Japan’s highest energy synchrotron radiation facility) and the Harima Observatory. This year they asked the first year doctor’s course students to come along to help, and to talk to the undergrads about our research. Looking forward to it. It will be a nice change of scenery.

Will try and write on Saturday evening after we get back. In the meantime, I’ve got an analysis meeting tomorrow morning before we set off which I have to study for.

April 14, 2006

Belle Is Back

Belle is now taking data again after the spring maintenance shutdown. The KEKB accelerator team have spent the last couple of days aligning and checking the condition of the beams, and they started collisions about 6PM yesterday.

The Belle event display can be seen live one the net here, or else it can be reached from the links in the bottom left corner of the Belle webpage.

The picture shows an end view of the detector. The electron and positron beams collide head on in the centre, and the charged particles that result from the collisions are captured as they spread out through the detector. A lot of the data we capture are Bhabha scattering events, where the positron and electron just scatter off each other and stop in the detector, like this:

But occasionally there is an interesting one where they annihilate and create new particles, like this one:

Usually we have a few troubles in the first week or so after we restart taking data, so it's normally a bad time to be on shift, but everything seems to be working well so far. Fingers crossed for the rest of the week.

(Updated photos.)

April 13, 2006

On-call Shift

I've spent most of the last week at uni with enrolment and orientation and all the other usual stuff we have to do at the beginning of the school year in April. Just popped up to the lab here in Tsukuba a couple of days ago, and I start the weeklong on-call shift this afternoon. Will write a bit more about the experiment later.

April 10, 2006


We had our annual hanami (flower viewing) drinks yesterday in Kobe. The weather was good, and there was a really good turnout. Most of the Kiwi students who have come over with Monbusho were there, including the new girl Susan from Napier, who it turns out was on the same flight as me on the way over. Everyone's busy with study and work, so it's been the first time I've seen most of them since last year.