Log in

Calibration & Tools

Calibrator Search Tool	The VLBA Calibrator Search Tool queries a database to find calibrators which are close to a specified celestial position, and optionally limit results by observing band and/or short baseline (<400 km) flux density.
Alternative VLBI Calibrator Search Engine	An alternative calibrator search tool is provided by Leonid Petrov. The observatory has no influence on the content of this tool and thus cannot guarantee the validity of the provided information. Use at your own risk.
Calibration Tables & Log Files	Information regarding automated calibration transfer for VLBA correlator output relevant to your scientific program, and for accessing key operations information, such as comments entered by the array operator during your observing.
Historic Polarization Calibrator Information	The goal of the polarization calibration program was to calibrate the polarization electric vector position angle by observing a network of sources with compact structure. The program was executed between 1999 and 2009. It was discontinued with the EVLA upgrade. Starting 2010, Polarization calibrator monitoring was performed only upon request by observers and in 2017 a regular monitoring was resumed executed during each VLA configuration change. Correlated visibilities of these observations can be found under the project code TPOL0003 in the NRAO archive. No calibrated data products are currently made available.
Detailed Performance Data	Detailed engineering and scientific performance data are available for pointing, system temperature and efficiency, and more.
EVN Sensitivity Calculator	The European VLBI Network (EVN) has made a sensitivity calculator that is very useful for non-heterogenous arrays but can also be used for VLBA-only experiments.
CLCOR/EOP offsets	EOP offsets due to CLCOR error in AIPS (2006 - 2011).

The National Radio Astronomy Observatory and Green Bank Observatory are facilities of the U.S. National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Founded in 1956, the NRAO provides state-of-the-art radio telescope facilities for use by the international scientific community. NRAO telescopes are open to all astronomers regardless of institutional or national affiliation. Observing time on NRAO telescopes is available on a competitive basis to qualified scientists after evaluation of research proposals on the basis of scientific merit, the capability of the instruments to do the work, and the availability of the telescope during the requested time. NRAO also provides both formal and informal programs in education and public outreach for teachers, students, the general public, and the media.