What spectral feature defines a Type II supernova?
Answer
Conspicuous display of hydrogen spectral lines
Type II supernovae are specifically defined by the presence of hydrogen spectral lines, meaning the star had not shed its massive outer envelope of hydrogen before detonating.
Frequently Asked Questions
What spectral feature defines a Type II supernova?What is the minimum initial mass required for a star to end its life as a Type II supernova?What atomic nucleus's formation in the core signals the definitive end of energy generation for the star?What is the fundamental energy characteristic of processes involving iron nuclei in the star's core?What quantum mechanical resistance fails when the iron core reaches a critical mass, initiating rapid collapse?What high-energy particles are massively released when protons and electrons combine into neutrons during the core's catastrophic implosion?What supports the core against further collapse once it reaches nuclear density ($10^{14}$ g/cm$^3$)?Which component carries away over 99% of the energy released during the core's conversion into neutrons?What process provides the necessary energy to re-energize the stalled shockwave near the nascent neutron star?If a star's initial mass was between $\sim 8$ and $25 M_{\odot}$, what is the typical remnant formed after the Type II supernova?What is the immediate physical consequence of the infalling outer layers slamming into the newly formed, incompressible core?