Contribution of patchy reconnection to the ion to electron temperature ratio in the Earth's magnetotail

Abstract. The ion to electron temperature ratio is a good indicator of the processes involved in the plasma sheet. Observations have suggested that patchy reconnection and the resulting earthward bursty bulk flows (BBFs) transport may be involved in causing the lower temperature ratios at smaller radial distances during southward IMF periods. In this paper, we theoretically estimate how patchy magnetic reconnection electric field accelerates ions and electrons differently. If both ions and electrons are non-adiabatically accelerated merely once in a single reconnection, the temperature ratio would be preserved. However, the ratio would not be preserved if particles are accelerated multiple times. As particles are transported earthward by BBFs after reconnection, the reflection of electrons from the ionosphere and subsequently multiple non-adiabatic accelerations at the reconnection site can explain the observed lower temperature ratios closer to the Earth.