"Introducing the CMS Guitar" photo session

I did a photo session at "LHC Point 5" where the CMS detector is located 100m underground. The area with the detector itself is not accessible due to ongoing collisions, but we also have a great 1:1 scale photo of the experiment there, which you can see in the photos below.

Go to this gallery on flickr to see the full set. All photos by Julia Hoffman.

First live performance

Here it is - video from the first live performance of the CMS guitar, less than a week after I finished putting it together:

MC Hammer

I'm still working on the videos from the Hardronic performance, so in the meantime I thought I'd share another video that I made recently. The song is "Hammer of a Down" - a blend of MC Hammer's "U Can't Touch This" together with "Chop Suey" by System of a Down. And the video is about... what happens when people working at CERN need a little break.
Check it out:


The video of the debut performance of the CMS guitar is coming very soon!!

CMS guitar @ Hardronic 2012

Wow.
This year's Hardronic broke all the records. We had over 1000 CERN personnel plus guests rocking out!!

The guitar played great. I tried to play great. The videos are coming, watch this space.

On the discovery of a new particle (Higgs?)

And so it happened today and we have announced the observation of a new particle at the LHC. CMS and ATLAS both  showed evidence on the level of "five sigma", which means that the probability that what they're seeing is just a result of pure chance is more or less the probability of rolling the dice eight times and getting a six each time.

This particle might be the Higgs boson - something that was postulated for the first time in 1964 and had since then escaped detection. The significance of this discovery is bigger than many people think. Some are calling it the biggest scientific achievement of the 21st century, and something bigger than the landing on the Moon - and I think they're right.

Let me try to put this into perspective, from the point of view of a physicist working on the same experiment but searching for different, yet undiscovered, particles. This will be a bit long, so bear with me.

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First of all - particle physics is what we call "fundamental research". We don't ask "what can I use this for?" or "whom can I sell it to and for how much?". We ask "why?". And we're trying to find answers to this question studying Nature at the deepest and most fundamental level - at tle level of interactions of particles that everything Science can describe is made of.

Its a bit like trying to solve a jigsaw puzzle. Blindfolded.

You reach into the box, hoping that your hand finds a new piece, and then try to arrange the pieces into something that makes sense.

And in fact in the 2nd half of 20th century we managed to arrange them pretty well, into something that we call the standard model of particle interactions. It's the most precisely measured theory to date. In the early 1990's it looked more or less like this:

You can see it looks pretty good, there are just two missing pieces. The one on the right was pretty obvious and it was found in 1995 by the experiments running on the Tevatron collider in Fermilab near Chicago. That's the top quark, the sixth particle in a family of particles making up the protons and neutrons in the atomic nuclei. Something that just had to be there.

The missing piece in the corner is something different. That's the Higgs boson. We need it to complete the puzzle, without it our theory is incomplete in an obvious way... but that's not the end of the story. You can see that the puzzle should extend in other directions, we believe that this is also the case with the standard model. We have many reasons to believe that the standard model is not the final, ultimate "theory of everything". In fact it doesn't even describe "everything" (it cannot describe gravity for example). But we have yet to see something new, some piece that would fit somewhere along the borders.

How are we looking for new pieces? We're reaching into the box where the pieces should be. Building stronger and stronger accelerators, we're able to reach further and further into the box. Remember, we can't see, we can just reach out and hope we find something.

And today we finally announced that our hand searching the box found a new piece:

At first glance it looks like it could be the missing one there in the corner. But checking whether it fits exactly will still take some time. This is the situation we're in at this moment.
What are the possible outcomes?

Option one
It is the standard Higgs boson. Everything fits. We have solved the puzzle... and unless we find some other new pieces in the meantime, we are starting to be in trouble:

we sort of expect there to be more to it, but we're not really sure where to start looking... game over?

Option two
It is some more exotic variant of the Higgs particle - it fits, but not exactly in the spot we thought initially:

this is much a better option as we would finally have a clear indication where to look for new things. Look: there's a whole new unpopulated row now!

Option three
It is something that ends up not fitting at all. I'd say its very unlikely, but possible - and would for sure be fun.

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And what is my part in the game? I, along with many other physicists, still have my hand in the box. We're still reaching out, way beyond the spot where the piece found today was lying. We're doing this in parallel to the Higgs searches, hoping that we will eventually find something like this:

A completely new particle, in a completely different place. Hinting at a lot more to come...

Higgs?

In this press release CERN is announcing a special seminar next week, on July 4th, where the ATLAS and CMS experiments will present recent results from the search for the Higgs boson. The Higgs boson is a particle that physisicts have been searching for for over 30 years now, its one of the things the Large Hadron Collider was built to look for. Its the final missing piece in the... puzzle we call the Standard Model - the theory describing the interactions of all known particles.

With the amount of data collected in 2012 we should be able to tell whether the hints we saw in 2011 were just statistical fluctuations that went away with more data, or whether they're still here - which would mean that we really are seeing... something.

So the question now is: should I rush to quickly finish the CMS Guitar in a week? :)

8 TeV collsions in CMS

Today in CMS we're celebrating first collisions at 8 TeV - the highest energy ever. This is the beginning of the 2012 data-taking run of the LHC collider. Take a look at the short video clip announcing this.

I better get to work on the guitar so that its ready when we discover some new particle ;-). With this new energy we're really expecting to see something new this year.

The CMS Detector

While I'm doing all this, why not introduce to you the CMS Detector itself?

The photo I'm using for the guitar is a head-on view of this 14000 ton piece of some of the most complex and precise machinery ever made, spanning a cylinder 21m long and 15m in diameter. The photo was taken without the "lids" (or, as we call them, endcaps) in place, so you can see the cylindrical "barrel" part with layers of different particle detection devices arranged in circles around the center.

This central point is the Interaction Point where particle collisions take place. Protons accelerated in the LHC (Large Hadron Collider) accelerator are smashed head-on 40 million times in every second. As the energy of the colliding protons is converted into matter, a few to over a hundred particles are created and fly outwards in all directions. The role of CMS is to detect them and measure their properties. Based on this information us physicists try to figure out what happened in the collisions, with hope of finding something new and unknown...

The diagram below should give you a sense of the geometry - and the scale (see the little guy down there?) of the experiment:

For more info check out these pages, for example.