Magnetic field map (in grey scale) from SDO/HMI of a part of the active region 11158, on February 15, 2011, at 01:48:00 UT. The orange and blue contours represent the positive and negative vertical electric current densities, respectively, with amplitude >100 mA/m². The green, cyan, yellow, and red contours are the X-ray emission (from RHESSI) at 12−18 keV, 18−26 keV, 26−40 keV, and 40−60 keV, respectively, integrated between b) 01:50:48 and 01:51:28 and c) 01:52:30 and 01:53:10 UT. X-rays have been imaged with the Visibility Forward Fit technique using collimators 2, 3, 4, 5, 6, 7, 8, and 9. The contours correspond to 50, 70, and 90% of the maximum for the X-ray emissions. The crosses are at the location of the maxima of the sources.