Best LOFAR high resolution image to date of Jupiter’s radiation belts, integrated over the entire 23 MHz band of observation distributed from 127 and 172 MHz, and a 7-h interval from ~19:00 to ~02:00 UT. The same image is displayed in both panels with color scale (left) and contours (right). The frequency-averaged clean beam size and shape (~18′′ × 16′′) are displayed in the bottom left of each panel. Pixel size is 1′′ × 1′′. Rms noise is 4.7 mJy/beam and the S/N (maximum peak flux divided by standard deviation) is 37. The S/N is approximately 14 at the 30% flux level (corresponding to the extremity of the emission). Dipolar field lines with apex at 1.5, 2, 2.5, 3, 3.5, 4 and 5 R_J are superimposed in the left panel. Contours superimposed in the right panel are derived from a rotation-averaged VLA image (obtained from Santos-Costa et al. 2009, in C band), which was convolved down to match the LOFAR observation angular resolution. Each set of contours represents relative intensity levels by steps of 10% of the maximum radiation peak: in the convolved VLA image (black line) and in the LOFAR image (red dotted line).