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Updated: Jun 5, 2026
06:46
Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic
Published on: August 25, 2016
Gamma-ray flares from the Crab Nebula.
A A Abdo1, M Ackermann, M Ajello
1National Research Council Research Associate, National Academy of Sciences, Washington, DC 20001, USA.
Science (New York, N.Y.)
|January 8, 2011
Summary
The Crab Nebula experienced two powerful gamma-ray flares in 2009 and 2010, indicating the presence of peta-electron-volt electrons. These energetic events challenge current theories of particle acceleration in astrophysical sources.
Area of Science:
- High-energy astrophysics
- Particle physics
- Observational astronomy
Background:
- The Crab Nebula is powered by a young, energetic pulsar.
- Pulsars are known to emit high-energy radiation.
Purpose of the Study:
- To describe and analyze two distinct gamma-ray flares from the Crab Nebula.
- To investigate the origin and energy of particles responsible for these flares.
Main Methods:
- Detection of gamma-ray flares using the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope.
- Analysis of gamma-ray flux and duration of the outbursts.
Main Results:
- Two gamma-ray flares were observed in February 2009 (16 days) and September 2010 (4 days).
- Gamma-ray flux increased by factors of four and six during the flares.
- Flares suggest emission from peta-electron-volt electrons in a compact region (<1.4 × 10(-2) parsecs).
Conclusions:
- The observed flares are associated with the highest-energy particles ever linked to a discrete astronomical source.
- The extreme energies challenge existing models of particle acceleration mechanisms.
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