Core-Collapse Supernovae (CCSNe)

Why in News?

A detailed study of SN 2023zcu, discovered in 2023 at the edge of the spiral galaxy NGC 2139, has provided insights that could help astronomers estimate distances in the local universe more accurately.

Key Highlights

• SN 2023zcu is located in the galaxy NGC 2139, approximately 90.7 million light-years from Earth.
• It belongs to the category of Core-Collapse Supernovae (CCSNe), among the most energetic stellar explosions in the universe.
• Detailed observations of its evolution can improve methods used to measure cosmic distances and understand stellar life cycles.

What are Core-Collapse Supernovae (CCSNe)?

• CCSNe occur when a massive star exhausts its nuclear fuel and can no longer counteract its own gravity.
• The star’s core collapses rapidly, triggering a powerful explosion that ejects its outer layers into space.
• These explosions enrich the universe with heavy elements essential for the formation of stars, planets, and life.

Type IIP Supernova

• Type IIP is the most common form of core-collapse supernova.
• It originates from a red supergiant star with a mass about 8–17 times that of the Sun.
• When the core collapses into a proto-neutron star, infalling material rebounds and generates a powerful shock wave.
• As the shock reaches the stellar surface, the outer layers are expelled, producing a brilliant explosion.

Evolution of a Type IIP Supernova

1. Core Collapse: The star’s core implodes after exhausting nuclear fuel.
2. Shock Breakout: A shock wave reaches the surface, causing a sudden increase in brightness.
3. Shock Cooling Phase: The expanding outer layers cool and gradually lose energy.
4. Plateau Phase: The supernova remains opaque and maintains nearly constant brightness for several months.
5. Nebular Phase: The ejected material becomes transparent, allowing observation of the inner regions.

Source: PIB