Left plots: light curves of RHESSI 100−300 keV HXR (HXR), GOES (1.0−8.0 Å) SXR (SXR), integrated HMI LOS magnetogram (LOS B), WL continuum (WL) and egression power (EGR). The HMI data products are integrated over the seismic signal. Black vertical dotted line denotes the sunquake onset time (22:18:37 UT) from time–distance diagrams (Fig. 3d). Continuum emission shows a peak emission at 22:18:37 UT, coincident with quake onset and LOS magnetogram transient. Egression power, normalised with respect to quiet sun levels, peaks above a defined detection threshold (red horizontal line) of the local mean (yellow) plus 5σ within the flare window (blue vertical lines). Right plots: photon flux spectrum for the time interval 22:18:16–22:19:12 UT with variable thermal (green) and thick-target bremstrahlung (green) fitting giving the total fit (red) over the 12−270 keV energy range (bounded in black; top) and respective residuals of fitting (bottom).