Spatial and temporal position of all 552 detected temperature peak events within 15 arcseconds from the center of the FOV and with a magnitude of at least 400 K. (a) Brightness temperature map of the first frame of the dataset (2 s integration). The black dotted circle marks a radial distance of 15″ from the center of the FOV. (b) The x-axis position and (c) the y-axis position of all brightness temperature peaks plotted against time, respectively. The events are all colored individually, showing the same color for the same event in all panels. (d) The x-axis and y-axis positions of all temperature peaks. The locations of a few selected events (A, B, C and D) that are studied in detail in Sect. 3.4 are marked with crosses in all panels.