On the faintest solar coronal hard X-rays observed with FOXSI

Understand

Solar nanoflares are small eruptive events releasing magnetic energy in the quiet corona.

• If nanoflares follow the same physics as their larger counterparts, they should emit hard X-rays (HXRs) but with a rather faint intensity.
• A copious and continuous presence of nanoflares would deliver enormous amounts of energy into the solar corona, possibly accounting for its high temperatures.
• To date, there has not been any direct observation of such sustained and persistent HXRs from the quiescent Sun.