Radiation Hydrodynamics of SN 1987A. I. Global Analysis of the Light Curve for the First 4 Months

The optical/UV light curves of SN 1987A are analyzed with the multi-energygroup radiation hydrodynamics code STELLA. The calculated monochromatic andbolometric light curves are compared with observations shortly after shockbreakout, during the early plateau, through the broad second maximum, andduring the earliest phase of the radioactive tail. We have concentrated on aprogenitor model calculated by Nomoto & Hashimoto and Saio, Nomoto, & Kato,which assumes that 14 solar masses of the stellar mass is ejected. Using thismodel, we have updated constraints on the explosion energy and the extent ofmixing in the ejecta. In particular, we determine the most likely range of E/M(explosion energy over ejecta mass) and R_0 (radius of the progenitor). Ingeneral, our best models have energies in the range E = (1.1 +/- 0.3) x 10^{51}ergs, and the agreement is better than in earlier, flux-limited diffusioncalculations for the same explosion energy. Our modeled B and V fluxes comparewell with observations, while the flux in U undershoots after about 10 days bya factor of a few, presumably due to NLTE and line transfer effects. We alsocompare our results with IUE observations, and a very good quantitativeagreement is found for the first days, and for one IUE band (2500-3000 A) aslong as for 3 months. We point out that the V flux estimated by McNaught &Zoltowski should probably be revised to a lower value.Comment: 27 pages AASTeX v.4.0 + 35 postscript figures. ApJ, accepte