Ask me... I'm an expert

Remember the posts about the Big Bang exhibition at the Science Museum? Well, if you haven't seen it yet hurry up. It's on until the 7th of October, after which it will be replaced by [not allowed to tell ;-) ].

To add a little more action to the displays the Science Museum set up a little interactive event last week where they would show some kit and have a couple of scientists explaining it. The plan was to have a cosmic ray detector and some Geiger counters. We provided the latter but they were quite useless in the end as nobody was able to bring anything even remotely radioactive to make them tick. So we concentrated on cosmic rays, which was not a bad idea anyway. Our colleagues from Bristol provided a scintillator and a small spark chamber, definitively the star of the show. It's much smaller than the huge one Imperial and RAL built long ago and we could not get to work again. At least the Bristol chamber worked nicely. Don't know if there's a lesson here...

It was a lot of fun explaining cosmic muons to the general public (although the general public found at the Science Museum is a quite biased sample) and answering the most unexpected questions. How do we know they are muons? Where do the cosmic rays come from? How does it work? Could they have triggered life? What's this black thing? (the trigger). Wouldn't the muons have all decayed before reaching the ground? (This guy knew more than expected). How do you get a satellite on orbit? Hmmm, somewhat unrelated, but I had a tag saying "asking me... I'm an expert" so I just had to know.

Many thanks to the Bristol guys David, Clare, Ben and John for providing the nice kit and to Will and Tom for representing Imperial.

Finally I agree with Gavin: we should try to build a similar chamber and display it on level 5.

Big Bang exhibition at the Science Museum

Some time ago I wrote about Fieldwork for the Science Museum and promised some updates. Back in February we were trying to repair an old spark chamber for an exhibition about the LHC at the Science Museum. The exhibition is now open but the spark chamber isn't there.

Dave spent a lot of time trying to repair the spark chamber and there is still a hope that it will go to the Science Museum. But it missed the deadline for the exhibition opening. The problem was with the trigger. The chamber is activated by two huge scintillators which produce a signal when a charged particle crosses. One is mounted below the chamber, the other is on top of it (it's the kind of gnu horns you can see on the picture in the original post). All the light guides (that guide the scintillation light to the photomultipliers) are broken. They can be repaired but that takes some time. Dave is working on that. As for the chamber itself, it looks OK. It produces nice sparks when activated by an almost random trigger.


The exhibition is essentially a huge cube of 5m size explaining in four zones what the LHC is about, how it works, how the detectors work and how the data will be analyzed. Or, well, as the exhibition is aimed at 14 to 17 year olds, it does not explain that much but gets a feel for how complicated and huge it is. The exhibition is actually called Big Bang (and that's what you'd read from the distance), as it's about recreating the conditions of the Big Bang in a laboratory. The illustrator made a great job drawing particles and collisions. I love his drawing of a cavern with all the ongoing activity! I won't say more. Come to the Science Museum (it's free) and see it.

The whole design process started (for me) in December where I attended a day long brainstorming session with 20 more physicists from various places in the UK. The team from the Science Museum was quite impressive at extracting as much information and ideas from us as they could. Of course many of them were not feasible, like putting a 1:1 picture of Atlas on the wall (rejected as it wouldn't fit: the museum is much too small!) or putting a real Grid node in the museum. Instead there's a lot of graphics, animations and small movies.

Then for several months we got spammed by the designer teams sending us text snippets to check for scientific accuracy. A month ago there was a meeting with the designer who explained us his ideas for the layout. Scientists and designers: two worlds collide... But we eventually managed to speak a common language.


Three weeks ago I got a mail asking if I was happy to be quoted in the exhibition saying "These high-energy collisions will replicate the conditions that occurred in the moments after the Big Bang, 13 billion years ago". I don't remember having ever said that and would have said 14 anyway... They obviously got a lot of quotes from the brainstorming session and wanted to match them with real scientists. So I agreed provided they change the age of the Universe (!). The result is shown in the picture.

Fieldwork for the Science Museum

This week I've been trying to fix a big spark chamber for the Science Museum with the precious help of Prof. Websdale. On the picture you can see him installing a scintillator on top of the chamber. I'm happy he accepted to help me because he used to build such devices in the past. I belong to the generation of particle physicist who remotely log on to a detector when it doesn't work and debug it by looking at the logfiles. In this case we use screwdrivers, a voltmeter and an oscilloscope. Something quite unusual for me...

I'm doing this because the I am LHCb-UK Outreach coordinator. As such I am supposed to coordinate the outreach activities in the UK of the LHCb experiment, i.e. explain to the average UK citizen what LHCb is doing. Since LHCb has very little manpower (to be taken as an euphemism) available for such activities there's hardly anything done. Please don't visit the public LHCb web-site, it's such a shame.

Yet as a CERN experiment we should devote part of our efforts explaining to the public what we are doing and why. CERN itself is an open laboratory with a quite decent public web-site.

What is more important in my activity as outreach coordinator is that I am part of the larger group of people who try to promote the LHC in the UK. What for? might you think, we have nothing to sell so why bother making an advertising campaign. That's the subtle difference between marketing and outreach. The UK taxpayers pay about £60M a year as a contribution to CERN and that's not counting what is paid to the research groups in the UK (my salary for instance). Some consider this as a contribution to culture: it's the price for increasing our understanding of Nature. Some might consider it as a long term investment in the future. Our economy is presently growing on the grounds laid during the first half of the past century, when quantum mechanics was developed (think of computers, mobile phones, microwave ovens, lasers...). We might be discovering now what the economy will be based on in 50 years (... or not).

In any case we owe the British public an explanation of what we do with the £1 each taxpayer spends every year to fund our research. We try to have contact with the media, we prepare material for teachers, we have set up a UK website about the LHC (here)... But we first had to find out what to tell the public. The buzzword is Big-Bang: the key message is that we are recreating the conditions of the Big-Bang in the laboratory. If you are interested in the details look at the result of the formative evaluation.

This message will also be central at the upcoming exhibition about the LHC at the Science Museum, for which I am part of the advisory panel. The exhibition will start in April and I am of course not supposed to tell you what it will show. Come and see it. There will for sure be a post here about its opening.

In order to show particles to the public the Science Museum wanted to have a "Cosmic Ray Detector" on display, a device that would show the path of cosmic rays. After some research I found out that they already had one, which Imperial College and Rutherford laboratory built for them some time ago, but that it was probably labeled "Spark Chamber" in their stores. They indeed managed to find it and now we are trying to get it operational.

Stay tuned, hopefully I'll soon be able to add another post about the successful outcome of this fieldwork.