How Hot Can Small Solar Flares Get?

The temperature reached by solar flares is a key parameter to understanding the physical process that causes the energy release. In this work, we analysed data from a Hinode Observing Programme that focused on high cadence measurement of the flaring plasma. This was carried out when the X-ray imager and spectrometer (STIX) on Solar Orbiter was observing. We analysed 3 small microflares, and determined their evolution and temperature. The temperature of the B2.8 microflare reached 16 MK. There was evidence in the smaller B1.4 flare of Fe xxiv emission, indicating that hot plasma of 15 MK can be reached.