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Variable very-high-energy gamma-ray emission from the microquasar LS I +61 303
1Universität Würzburg, D-97074 Würzburg, Germany.
Science (New York, N.Y.)
|May 20, 2006
Summary
We detected variable gamma-ray emissions from the microquasar LS I 61 + 303, suggesting periodic activity. This finding offers insights into the physics of relativistic jets and cosmic ray origins.
Area of Science:
- Astrophysics
- High-energy astrophysics
- Gamma-ray astronomy
Background:
- Microquasars are binary systems emitting relativistic jets, crucial for studying cosmic rays and jet physics.
- Understanding microquasar emissions aids in unraveling high-energy astrophysical phenomena.
Purpose of the Study:
- To report the detection of variable gamma-ray emission from the microquasar LS I 61 + 303.
- To investigate the periodicity and orbital modulation of gamma-ray emissions in microquasars.
Main Methods:
- Utilizing gamma-ray telescopes to detect emissions above 100 gigaelectron volts.
- Analyzing six orbital cycles of the microquasar LS I 61 + 303.
- Correlating gamma-ray emission patterns with the orbital phase of the binary system.
Main Results:
- Detection of variable gamma-ray emission above 100 GeV from LS I 61 + 303.
- Observed periodicity in gamma-ray detections, coinciding with specific orbital phases.
- Strongest gamma-ray emission not detected at the closest stellar approach, indicating orbital modulation.
Conclusions:
- The microquasar LS I 61 + 303 exhibits periodic gamma-ray emission.
- Orbital modulation significantly influences the observed emission or absorption processes.
- These findings contribute to understanding microquasar physics and their role as cosmic ray sources.
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