First run of the LHC as a heavy-ion collider

A year of LHC operation typically consists of an extended run with colliding protons, ending with a month in which the LHC has to switch to its second role as a heavy ion collider and provide a useful integrated luminosity to three experiments. The first such run in November 2010 demonstrated that this is feasible. Commissioning was extremely rapid, with collisions of Pb nuclei achieved within 54 h of first injection. Stable beams for physics data-taking were declared a little over one day later and the final integrated luminosity substantially exceeded expectations..