Nature 506, 343–348 (2014); doi:10.1038/nature13008

In the legend to Fig. 2 of this Letter, we should have acknowledged the X-ray and neutron imaging as follows: X-ray image analysis1,2 was performed by N. Izumi, S. Khan, L. R. Benedetti, R. Town and D. Bradley of the NIF Shape working group of Lawrence Livermore National Laboratory, California, USA, and by authors T.M. and A.P. Neutron images were measured3 and analysed4,5 by D. Fittinghoff of the Lawrence Livermore National Laboratory, California, USA, and by G. Grim, N. Guler, F. Merrill, C. Wilde and P. Volegov of the Physics Division at the Los Alamos National Laboratory, New Mexico, USA.