单星模型的行星状星云演化。中性尖峰的形成

presented for the formation up to the late evolution of planetary nebula, for 6 different stellar models from 1 to 5 Mo. The hydrodynamical models use stellar evolution calculations as inner boundary conditions and updated values for the number of ionizing photons. Special emphasis is placed on the formation of neutral spikes, as recently observed by the James Webb Space Telescope. The results indicate that neutral spikes can be detected either at the formation of planetary nebulae or in their decline. In the first case, the temporal window decreases with the mass of the model, ranging from 3,000 years in the 1 Mo case to 0 for 5 Mo. In the second case, only the 1.5, 2.0, and 2.5 Mo cases allow us to detect the neutral spikes for most of the remaining time.