The rediscovery of physics at the LHC progresses with ATLAS showing the first candidate events for the Z-boson. These were first discovered in 1983 at CERN using the smaller SPS collider which now serves as the injection ring for the LHC. ATLAS and the other LHC experiments have been seeing plenty of Z-bosons but we outsiders have to wait for them to approve the reports before we can see them. The next physics milestone will be observations of the top quark which was discovered at the Tevatron in 1995.
Peak luminosity in ATLAS is currently 7.7 x 1027 cm-2s-1. Over the next few weeks they plan to increase this in a series of doubling steps. The process has been going very smoothly thanks to the good performance of the magnets and cryogenics. The plot below using a log scale shows how the integrated luminosity has been increasing exponentially with a thousand factor improvement in less than two months. The LHC controllers will want to see this trend continuing until luminosity is reached at about 10000 times current levels towards the end of the summer. One of the main bottlenecks holding up faster progress is the need to train the shift staff that control the LHC so that they all know how to deal with any issues that have been found.