Sunday, 22 November 2009
Nice to see that Catalan schools are in the blogosphere... and that they had a nice time listening to my LHC stories.
ATLAS has provided a nice monitoring page where we can follow the progress of data distribution in these so exciting moments of first circulating beam in the LHC. This is not collisions yet, but real data indeed. After so many years of simulations, we are happy to see the first Megabytes of real stuff. In the picture, I have just captured the current status of the datasets distribution to Tier-1s and from there to the associated Tier-2s. The overall picture looks pretty green, which is good news. PIC received the subscribed data with no problems and promptly redistributed it to the Tier-2s. It looks the data movement went mostly smooth. Let's keep an eye on this. We will see the rates growing in the next days.
So, there we go. Last friday 20th November beams circulated again inside the LHC, after one long year of reparations. Everyone is happy and bottles of champain (or cava) are being opened in the control rooms. In the picture you can see, besides the party atmosphere at the LHC control room, the first event displays from ATLAS, CMS and LHCb . The hundreds of tracks coming from the collimators where beams are splashed can be clearly seen in all of them. We are watching the first LHC data.
Commencing countdown, engines on...
Tuesday, 10 November 2009
Low energy protons from the LHC were dumped in a collimator just upstream of the CMS cavern. The calorimeters and the muon chambers of the experiment saw the tracks left by particles coming from the dumping point (a so-called 'splash event', see images). During the rest of the weekend, bunches of protons were also sent in the clockwise direction passing through the ALICE detector and were dumped at point 3.
All detectors saw 'splash' events on their monitoring pages. Castor and the Preshower detectors saw particles for the first time! Some beautiful pictures from the events seen: