The Green Bank Interferometer (GBI)
is operated by the National Radio Astronomy Observatory
at its Green Bank
site in West Virginia. It includes three radio telescopes of 85-foot
(26m) diameter, designated 85-1, 85-3, and 85-2 from left to right
in the above picture. (85-1 is also known as the
is devoted to continuous monitoring of pulsars; 85-1 and
85-2 form a one-baseline interferometer.
Note: the GBI monitoring program has ceased as of October 6, 2000,
due to lack of funding.
Anyone interested in using the GBI who may be able to provide operating
funds should contact Phil Jewell (pjewell at nrao.edu).
Credits: The Green Bank Interferometer is a facility of the
National Science Foundation operated by the National Radio Astronomy Observatory.
From 1978-1996, it was operated in support of USNO and NRL geodetic
and astronomy programs; after 1996 in support of NASA High Energy Astrophysics
Technical Data: 2-element interferometer.
Baseline: 2400 meters at an azimuth of 62 degrees (E of N).
Bands: 8.3 GHz (X-band) and 2.25 GHz (S-band) with 35 MHz bandwidth.
Receivers: Cryogenically cooled, dual frequency, dual polarization.
Both X and S bands simultaneously observed in both right and left circular
System temperature: About 35 K in Sband and 45 K in Xband.
Sensitivity: RMS noise in a 5-minute scan is about 6 mJy in S-band
and 10 mJy in X-band for point sources.
Minimum integration time: 30 seconds.
Resolution: About 3 arcseconds fringe at X-band and 11 arcseconds
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email@example.com last changed this page 06 Oct 2000