2026ApJ...996...32K

The rising phase toward the optical maximum of a classical nova is one of the last frontiers of nova study. Constructing free-free emission model light curves based on our fully self-consistent nova explosion models, we present several theoretical light curves of classical novae and compare them with the four novae having the observed rising phase toward the optical maximum. Our 1.25 M_⊙ white dwarf (WD) models show excellent agreements with the light curves of KT Eri, V339 Del, and V597 Pup, while our 1.35 M_⊙ WD models are consistent with the light curves of SMC NOVA 2016-10a. These agreements indicate that the light curves toward the optical maximum of these novae are dominated by free-free emission, rather than by photospheric emission. Our results justify the previously obtained WD masses and distance moduli for these novae and show that the postmaximum evolution can be well approximated with the evolution sequences of steady-state envelope solutions.