
Steve Myers, opening our workshop yesterday morning.
For the last two and a half days I’ve been at CERN, for a variety of meetings, including a two day workshop on the possibilities of a demonstration experiment for proton-driven plasma wakefield acceleration. I’ve blogged about this idea a while back, now a group is coming together to work towards an experimental verification of those ideas. A really positive message from this meeting is that CERN is interested, crucial since such a project can not be undertaken without the support of a strong accelerator laboratory. Steve Myers, the director for accelerators and technology at CERN, opened the workshop yesterday morning. For the last two days, accelerator experts, plasma experts and detector people have been discussing possibilities for the construction and operation of long cells of plasma, for the creation of very short packets of highly energetic protons and the like. The goal of the experiment will be to demonstrate high acceleration gradients, way beyond what conventional accelerators can achieve nowadays. If that works, who knows where this could go? A brand new solution for future particle physics experiments at the energy frontier is something we are all hoping for…

A possible site for the experiment: A steep transfer tunnel from the SPS to the CERN West Area.
We also managed to squeeze in a visit to a potential site for the experiment: A currently unused tunnel that connects the West Area (a huge experimental hall at CERN) with the SPS (the Super Proton Synchrotron, one of the accelerators here at CERN, and the final injector for the LHC). Since the SPS is something like 50 m underground, the tunnel has quite a steep slope. Here, a system for the compression of the proton packets from the accelerator could be set up, if we come up with a clever, cost efficient way to realize this. The plasma cell that will provide the acceleration would then probably be on flat ground at surface level in the experimental hall. On the picture you can see a few elements that are still left from the previous beam line in the tunnel. Now the details of the experiment have to be worked out, and a proposal to CERN has to be formulated. Exciting times are ahead, as a new project gets born.
Being at CERN at this very last day of the year that CERN is still open also gave me the opportunity to see the last LHC report of this year, where the accelerator and the experiments reported on their progress. Given the recent fantastic success of the LHC commissioning and first physics running, this event was a celebration of amazing first results achieved by incredibly well working detectors and by a smoothly running LHC. We were all sent off by Rolf Heuer, CERN’s director general, with best wishes for Christmas and for a happy new year, and the request to come back well rested for all the great things that lie ahead.
Today, it has started to snow here in Geneva, all of CERN is covered in a few white fluffy centimeters… And people are getting into a holiday mood. In a few minutes I’ll leave for the airport, my last flight (finally!) for this year…

Standing room only in the CERN Main Auditorium for the LHC Reports, as Fabiola Gianotti, the ATLAS Spokesperson, gives her talk.