IVS (VLBI) Analysis Center for Source Structure

USNO operates the International VLBI Service for Geodesy and Astrometry (IVS) Analysis Centers for Source Structure (VLBI). The purpose of this Analysis Center is to provide (primarily) radio frequency images of International Celestial Reference Frame (ICRF) sources, intrinsic structure models derived from the radio images, and an assessment of the astrometric quality of the ICRF sources based on their intrinsic structure in order to support definition and maintenance of the celestial reference frame for the IVS and the international astronomical and geodetic communities.

The primary service of the Analysis Center is to maintain a Web-accessible data archive of radio frequency images of ICRF sources. Imaging observations are planned and executed using both IVS radio astronomy telescopes as well as the Very Long Baseline Array (VLBA), a ten-station homogeneous array of 25 m radio telescopes operated by the National Radio Astronomical Observatories for the National Science Foundation. Center personnel then correlate and calibrate the imaging data and make it available via a Web interface. Historically, this Web-accessible data archive was called the Radio Reference Frame Image Database (RRFID). We are updating this service and renaming it the Fundamental Reference Image Data Archive (FRIDA). Ultimately, this will include both radio and non-radio data.

Along the left of the page, we provide access to USNO IVS Source Structure Analysis Center
products. Below, you will find links to the IVS. For more information on the activities of
USNO’s IVS Source Structure Analysis Center (VLBI), click here .

IVS Analysis Centers
Most recent USNO IVS Source Structure Analysis Center (VLBI) annual report