A Type I supernova that shows weak or no helium lines and no strong silicon (Si II) absorption feature near 6150 Å. Type Ic supernovae are believed to result from the evolution of massive stars.
A supernova type whose spectrum contains hydrogen lines. Compared with Type I supernovae, its light curve has a broader peak at maximum and dies away more rapidly. The magnitudes are smaller, ranging
from M_V = -12 to -13.5, and the ejecta have lower velocities (about 5,000 km/sec). These supernovae, which result from the final evolution of massive stars, have three main divisions: Type II-P, Type II-L, and Type II-n.
A supernova type whose spectrum contains hydrogen lines. Compared with Type I supernovae, its light curve has a broader peak at maximum and dies away more rapidly. The magnitudes are smaller, ranging
from M_V = -12 to -13.5, and the ejecta have lower velocities (about 5,000 km/sec). These supernovae, which result from the final evolution of massive stars, have three main divisions: Type II-P, Type II-L, and Type II-n.