Recent Breakthroughs in VHF Interferometry
Abstract
The NRL-National Radio Astronomy Observatory 74 MHz (4-m wavelength) receiver system on the Very Large Array (VLA) telescope (an array of 27 25-m radio antennas located in Socorro, New Mexico) has, for the first time, demonstrated the capacity for both high sensitivity and high angular resolution observations in the VHF band. A number of instrumental, algorithmic, and computational advances have allowed us to compensate for the ionospheric phase corruptions that have made high-resolution imaging a challenge at such a long wavelength until now. This project has turned the VLA, previously a centimeter-wavelength instrument, into the world's most capable meter-wavelength instrument, in which we regularly achieve resolutions as small as 150 microradians. This capability has enabled us to embark on many scientific projects. It has also spawned plans for building even more capable long-wavelength instruments such as the Long Wavelength Array (LWA), which an NRL-led collaboration is now developing. In this article, we describe two of the many projects now ongoing: the VLA Low Frequency Sky Survey, and probing even higher resolutions by extending the 74 MHz receivers to the nearby Pie Town (New Mexico) station.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2005
- Accession Number
- ADA520224
Entities
People
- A. S. Cohen
- J. J. Condon
- Namir Kassim
- R. A. Perley
- T. Joseph W. Lazio
- W. C. Erickson
- W. D. Cotton
- W. M. Lane
Organizations
- United States Naval Research Laboratory