Report from the NA61/SHINE experiment at the CERN SPS

This document reports on the status and plans of the NA61/SHINE experiment at the CERN SPS as of October 2011. First, progress on detector upgrades and overviews of the 2010 and 2011 data taking periods are presented. The NA61 facility is ready for data taking with ion beams. Second, the advance in the NA61 software, data calibration and the data analysis is reported. In particular, first NA61/SHINE charged pion spectra in p+C interactions at 31 GeVc were recently published. Here we also present preliminary results on K+ spectra. Both data sets have already been used for improving the neutrino beam flux predictions in the T2KThird, new results from LHC and RHIC relevant for the NA49 evidence of the onset of deconfinement are reviewed and their impact on the NA61 ion program is discussed. Finally, plans for data taking in 2012, 2014 and 2015 are outlined in view of the scheduled stop of the CERN accelerators in 2013. Recent developments underline the urgency of carrying out the NA61/SHINE ion program as soon as technically possible. In particular, the most urgent data for this program, central Ar+Ca collisions at 13A, 20A, 30A, 40A, 80A and 158A GeVc should be taken with as little delay as possible. It is also crucial to complete the energy scan with secondary Be beams in 2011 and 2012. experiment.