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Related Experiment Video

Updated: Jul 12, 2026

Visualization of Low-Level Gamma Radiation Sources Using a Low-Cost, High-Sensitivity, Omnidirectional Compton Camera

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Very high energy gamma-ray binary stars.

R C Lamb, T C Weekes

Science (New York, N.Y.)

|December 11, 1987

Summary

Astronomers discovered very high-energy gamma-ray binaries, systems with neutron stars emitting powerful radiation. These findings suggest similar galactic sources may produce cosmic rays observed on Earth.

Area of Science:

Astronomy and Astrophysics
High-Energy Astrophysics
X-ray Astronomy

Background:

Luminous x-ray binary star systems, emitting photons from 0.1 to 10 kiloelectron volts, were a major discovery.
Recent observations reveal some of these systems also emit photons above 10(12) electron volts, indicating very high-energy phenomena.

Purpose of the Study:

To report the discovery and characteristics of very high-energy gamma-ray binaries.
To discuss the implications of these discoveries for understanding cosmic ray origins.

Main Methods:

Detection of very high-energy gamma-ray emission using ground-based techniques.
Observation of four specific binary sources: Hercules X-1, 4U0115+63, Vela X-1, and Cygnus X-3 by independent groups.

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Last Updated: Jul 12, 2026

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20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

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Main Results:

Confirmation of very high-energy gamma-ray emission from binary sources containing rotating neutron stars.
Observation of four specific sources (Hercules X-1, 4U0115+63, Vela X-1, Cygnus X-3) by multiple independent research groups.

Conclusions:

The existence of very high-energy gamma-ray binaries was not initially predicted but is now supported by observational evidence.
These sources are potential contributors to the population of energetic cosmic rays detected on Earth, originating from similar galactic sources over the past few million years.