of Novae in Outburst'
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Introduction
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A nova is a thermonuclear explosion event on a mass-accreting white dwarf (WD) in a close binary. When the mass of the hydrogen-rich envelope on the WD reaches a critical value, hydrogen ignites at the bottom of the hydrogen-rich envelope to trigger a nova explosion. Then, the envelope expands to a red-giant size and emits strong winds [@kat94h]. After the maximum expansion of the photosphere (when the maximum wind mass-loss rate is attained), the photospheric radius begins to shrink and the photospheric temperature rises with time. The main emitting wavelength region thus shifts from optical to UV and supersoft X-ray [see, e.g., Figure 23 of @hac06kb for V1974 Cyg]. A large part of the hydrogen-rich envelope is blown in the wind. The wind stops and the nova enters a supersoft X-ray source (SSS) phase. The envelope mass decreases further by nuclear burning. When it decreases to below the critical mass (minimum mass for steady hydrogen shell-burning), nuclear burning extinguishes. The WD cools down and the nova outburst ends. These evolutions of novae are briefly summarized in @hac17k.

Evolutions of nova outbursts can be followed by the optically thick wind theory. @kat94h calculated nova 