Universe 

Gamma-Rays from High-Mass X-Ray Binaries

In its first year, NASA's Fermi Gamma-ray Space Telescope discovered GeV (billions of electron volts) intensity variations revealing orbital motion in high-mass X-ray binaries (HMXBs). These are systems where a compact companion, such as a neutron star or a black hole, rapidly orbits a hot, young, massive star. The first examples include LSI +61 303, which sports a 26-day orbital period, and LS 5039 (3.9 days). This animation shows such a system. When the compact object lies far from its host star, TeV (trillions of electron volts) gamma-rays (white) are seen by ground-based gamma-ray observatories. But, as the object plunges closer to the star, the TeV emission is quenched and GeV emission turns on. Interactions by accelerated particles from the compact source with gas encircling the star — or in some systems, the star's light itself — is thought to be responsible for this change.


Credits

Walt Feimer (HTSI): Lead Animator
Francis Reddy (SPSYS): Writer
Please give credit for this item to:
Walt Feimer, NASA/Goddard Space Flight Center

Short URL to share this page:
http://svs.gsfc.nasa.gov/goto?10507

Missions:
Fermi Gamma-ray Space Telescope
GLAST
Swift

Data Used:
Fermi None
Swift None

This item is part of these series:
Fermi
Astrophysics Animations

Keywords:
SVS >> Gamma Ray
SVS >> HDTV
SVS >> Neutron Star
DLESE >> Space science
SVS >> X-ray
SVS >> Gamma Ray Burst
SVS >> Astrophysics
SVS >> Universe
SVS >> GLAST
SVS >> Space
SVS >> Gamma Ray Observatory
SVS >> Fermi
SVS >> Binary Star
SVS >> Binary
NASA Science >> Universe