This is the second of two papers dedicated to the brightening of a coronal loop observed by the Transition Region and Coronal Explorer (TRACE) on 1998 June 26; it aims at hydrodynamic modeling of the brightening. Since the loop geometry is practically unchanged during the brightening, the evolution of the plasma confined in the loop is described with a one-dimensional hydrodynamic time-dependent numerical model, and from the results the emission along the loop in the TRACE 171 ? band is synthesized. The information from Paper I is used to derive the geometry and the initial configuration of the loop as well as for comparison with the results of the model. The modeling is focused to determine the amount, spatial distribution, and evolution of the heating deposited in the loop to make the modeled evolution close to that observed with TRACE. We find that, in order to match the observed evolution and distribution of the brightness along the loop, the heating has to be nonsymmetrical in the loop, in particular, deposited between the apex and one footpoint (3 × 109 cm from the southern footpoint). A reasonable match with observations is obtained by assuming that the heating is switched on abruptly and then kept constant for the whole rising phase. An even better match is obtained with the heating high and constant for 100 s and then decaying exponentially with an e-folding time of 300 s. We discuss the resulting physical scenario; a bright irregular structure close to the loop in the TRACE images may be a tracer of the heating release.
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