Chromospheric Heating: conduction fronts (II)

Velocities
Forbes et al. predict very small evaporative flows: v ? 5 km/s Recent numerical reconnection model of Yokoyama & Shibata (1997) includes conduction and yields evaporative upflows with speeds ~0.2 - 0.3 x the local sound speed: v ? 40 km/s

w = 9 x 104 km

Thus, our observations suggest that conduction front heating of the
chromosphere dominates at this stage of the flare. This agrees well with the conclusions of Falchi, Qiu & Cauzzi (1997) who detected 20-30 km/s downflows at the outer edge of Ha ribbons in the decay phase of an M2.6 flare.

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