Home | Sitemap | Contact us
this site all CERN
Physics Banner - nucleus, hadron, and QCD particle's artistic representation

LHC restart - Monday 23 November 2009

see some photographs from the ALICE Control Room (23-11-2009)

taken by Fons taken by Sylvain taken by Anton taken by Jan Fiete taken by Federico and a short video

16:47 Two beams circulating in the LHC

SDD data SDD data

16:47 Within seconds the first event (see above) from colliding proton beams is showing up on the ALICE detector event display.

A handful of tracks have been reconstructed in the Silicon Pixel Detector (SPD) pointing back to a unique vertex.

Events keep "pouring in" at a rate of about 10 per minute. The LHC operators must have managed a direct hit between the two beams immediately! Well done folks! Great work!

Over the next 40 minutes almost 300 events showed up.

SDD data

Primary vertex distribution (the point where the interactions happened) in the transverse plane (xy) and along the beam axis (z) reconstructed in real time by the Online Computer Farm of the High Level Trigger. The histograms contain 191 events.

SDD data SDD data SDD data

Here is another example of a nice event !! (Run 101498, Event 48, 16:58:48)

and here is a link to a 3D animation of an event

Two circulating beams