Universe  ID: 20122

Fermi's LAT Instrument

Fermi's Large Area Telescope (LAT) detects particles produced in a physical process known as pair production that epitomizes Einstein's famous equation, E=mc2. When a gamma ray, which is pure energy (E), slams into a layer of tungsten in one of the tracking towers that compose the LAT, it creates mass (m) in the form of a pair of subatomic particles, an electron and its antimatter counterpart, a positron. Several layers of high-precision silicon detectors track the particles as they move through the instrument. The direction of the incoming gamma ray is determined by projecting the particle paths backward. The particles travel through the trackers until they reach a separate detector called a calorimeter, which absorbs and measures their energies. The LAT produces gamma-ray images of astronomical objects, while also determining the energy of each detected gamma ray.


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Animation Credits

Chris Meaney (HTSI): Lead Animator
Steven Ritz (NASA/GSFC): Scientist
Please give credit for this item to:
NASA's Goddard Space Flight Center Conceptual Image Lab

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Fermi Gamma-ray Space Telescope

Data Used:
Note: While we identify the data sets used in these visualizations, we do not store any further details nor the data sets themselves on our site.

This item is part of these series:
GLAST Pre-Launch
Astrophysics Animations

Goddard TV Tape:
G2007-011HD -- GLAST Pre-Launch Resource Tape

SVS >> Satellite
SVS >> Spacecraft
DLESE >> Space science
GCMD >> Earth Science >> Spectral/Engineering >> Gamma Ray
SVS >> Gamma Ray Burst
SVS >> Astrophysics
SVS >> Universe
SVS >> Space
SVS >> Gamma Ray Observatory
SVS >> Fermi
NASA Science >> Universe

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version