Hot protons in the inner corona and their effect on the flow properties of the solar wind

Abstract

Following recent observations which indicate the presence of extremely high flow speeds in the inner corona, 700 – 800 km s−1 below 10 RS, and the possible presence of very high proton temperatures, 3 × 106 ≤ Tp ≤ 8.5 × 106 K, we present a parameter study which shows that if the high proton temperatures in the inner corona are genuine, then flow speeds of 700 to 800 km s−1 can readily be achieved at 10 RS or even closer to the coronal base. If one allows for both heat and momentum deposition in the inner corona, the rapid acceleration close to the coronal base can be achieved with proton temperatures well below the upper limit placed by the observations.