Afterglow

Definition

Afterglow is the emission that follows a gamma-ray burst (GRB) and can be observed across various wavelengths, including X-rays, optical, and radio. It provides crucial information about the environment surrounding the GRB and the mechanisms driving these powerful cosmic events.

5 Must Know Facts For Your Next Test

1. Afterglows are typically observed in X-rays shortly after the initial gamma-ray burst and can last from days to weeks.
2. The afterglow's light curve usually shows a fading brightness over time, following a power-law decay.
3. Observing afterglows helps astronomers determine the distance to gamma-ray bursts using redshift measurements.
4. The study of afterglows has led to significant insights into the progenitors of GRBs, such as massive star collapses or neutron star mergers.
5. Multi-wavelength observations of afterglows contribute to understanding the interaction between the ejected material from the GRB and the surrounding interstellar medium.

Review Questions

Related terms

Gamma-Ray Burst (GRB): A brief but extremely energetic explosion in space, often associated with massive star collapse or neutron star mergers.

Redshift:

A phenomenon where light from distant objects is shifted towards longer wavelengths due to the expansion of the universe, used to measure distances in astronomy.

Interstellar Medium:

The matter—composed of gas and dust—that exists in space between stars within a galaxy, playing a role in star formation and other cosmic events.