Coronal loop heating by random energy releases

It was suggested by Parker that the solar corona is heated by numerous small localized events called nanoflares. High-resolution satellites (the Solar and Heliospheric Observatory and Transition Region and Coronal Explorer [TRACE]) have shown a kind of very small scale activity at transition region temperatures (i.e., explosive events, microflares, blinkers, etc.). These events may serve as the building blocks of the heating mechanism(s) of the solar atmosphere. In this Letter we present the results of numerical calculations that detail the response of the coronal plasma to microscale heating pulses in a magnetic loop. The energy input pulses are at periodical and random injections, located near the footpoint where the temperature is approximate to10(4) K. It is found that these successive energy inputs can maintain the plasma along the loop at typical coronal temperatures. This result is in good qualitative agreement with TRACE observations studied by Aschwanden et al.