Since I spend much of my time studying the resulting debris from protons destroyed in LHC collisions, I was a little nervous as to how one of them might react to being interviewed. But he seemed relaxed, and positive.

JMB: "It's been quite a year! You are famously a very stable chap, but did the excitement get too much for you at any point?"
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A Higgs boson decaying to two photons via a quantum loop.

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We have a large windowless meeting room at Argonne with an old-fashioned pull-down projector screen. When I walked in there yesterday morning for the CERN videolink I was greeted by 30-odd ashen-faced physicists. Oh lord, I thought, there has been a terrible accident. The accident, it turns out, was comic sans.

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I know I ought to post some careful analysis after that seminar, but I am very tired and busy so for now here's a limerick.

What can I say? You just have to see it ...

Jon Butterworth: An important cross-check of the OPERA result – pulses instead of blobs – comes up with the same weird answer

Lily Asquith on the awesome power of the genie in the proton

I vaguely know Jon. This means I remember being in the same group having a beer together at CERN. But, then, he's well known for this blog so I would remember him. We crossed paths (again?) at the presentation of the famous OPERA results at CERN a few weeks back. Jon was kind enough to remember me but the sting in the tail was a comment that a contribution to his Blog would be welcome. A comment that I would probably have forgotten but for the fact I'm on a transatlantic plane for the third time this month and I've seen all the films. Half of Jon's blog entries seem to be written on a plane so why don't I have a go?

Why am I on a plane? Well, I think Jon has explained that particle physics is a world-wide endeavour these days, and this extends to the supporting acts, not just the physicists. Fermilab, where Lily works, produced some key pieces of the LHC accelerator and is a so-called Tier 1 centre in the world-wide computing Grid that enables Jon and his colleagues to turn all the data coming out of their experiments into results they can publish in papers. I'm on my way to a meeting in Vancouver of HEPiX - a worldwide collaboration of computing centres that started in HEP but now extends to include computing centres for other disciplines such as Genome research. Why Vancouver? Because this is home to yet another Tier 1 Centre, TRIUMF.

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I have just finished my first ever set of shifts in the ATLAS control room, and now I feel like a proper physicist.

I did three eight-hour shifts. The first two were boring as hell as we had no beam, but this was probably a good thing as I didn't take the shadow shifts that I was supposed to do, and so arrived in the control room on Friday morning with almost no idea what I was going to do.

ATLAS control room, taken by my long-suffering colleague David Miller

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I'm writing this on the plane from Barcelona to Geneva. In Barcelona, I was on the committee which examined the doctoral thesis of Francesc Vives, a student at UAB. He did very well and is now Dr. Francesc (congratulations).

ATLAS en Català.

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A graphical representation of a proton-proton collision. Loosely speaking, the red, yellow and some blue bits are the skeleton, and the green stuff is squishy. Credit: Frank Krauss, Sherpa.

We're measuring all kinds of stuff at the Large Hadron Collider right now. The question we're addressing could be summed up as

Does the Standard Model of particle physics work at LHC energies or not?

If it works, there is a Higgs boson but not much else new. If it doesn't, there might not be a Higgs but there must be something weird and new going on. As I have said before, the energy range of the LHC is special.

This begs the question (of me at least)

How well do we really understand the predictions of the Standard Model at these energies?

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LHSee on my phone. An ATLAS collision event.

I really shouldn't be doing this at the weekend, but I am impressed by this android app. There's a nice "Hunt the Higgs" game and some informative links, but the main thing is you can download live LHC collisions events as they are recorded by the ATLAS experiment. The you can zoom them, rotate them and so on, see below:

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Jon Butterworth: Diary entry. An unexpected bonus of the faster-than-light neutrino kerfuffle was a trip to the Palais de Nations and a superbly retro BBC studio.

Jon Butterworth: On Friday the Tevatron closes after 28 glorious years. There will be many tributes, here's one. To the edge of physics by bicycle

As you have probably noticed by now, neutrinos from one of the accelerators at CERN are regularly fired 730 km through the Alps and across Italy to the Gran Sasso lab, where some of them are detected by the Opera experiment.

This experiment is designed to measure how the neutrinos change their properties as they go. But they also have some very precise GPS positions and timing measurements. So they know the distance the neutrinos travel, they know how long it takes them, and they can therefore measure the speed. Since neutrinos have a tiny mass, the speed should be very close to the speed of light. But their measurement seems to show the neutrinos arriving early - travelling faster than the speed of light.
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