Chromospheric magnetic reconnection and its implication for coronal heating

According to recent data analyses, the relationship between the coronal-ene rgy flux density and the photospheric magnetic flux density is approximatel y power law; estimates of the exponent tend to be noninteger and fall in th e range 1-2. The Index is closer red 2 or quiet regions and loser to 1 for active regions. We here examine this relationship on the basis of a recent model of coronal heating. We assume that the coronal energy flux is derived from reconnection of neighboring flux tubes at the level of the chromosphe re and we examine the rate at which such reconnection would occur in terms of a simple kinetic-theory model bn this model flux elements appear randoml y within supergranulation cells, are carried into the network according to a prescribed velocity held and cancel in;the network due to "collisions" be tween elements of opposite polarity. For any limited range of magnetic flux density, the relationship is;approximately power law. We find ;that the po wer-law index Is in the range 1-2: for weal fields it is close to 2, and fo r strong fields a is close to 1, in agreement with available evidence.