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More information

For more information, please visit the LWA Consolidated Information Site at lwa.unm.edu.

LWA memo series

ECE’s Steve Ellingson maintains the Long Wavelength Array Memo Series website, which gathers submissions from all the project participants.

Long wavelength array

A field of antennas (Photograph courtesy of J. Craig, University of New Mexico)

A large radio telescope that is expected to eventually span a 400-kilometer region of New Mexico is under construction to study interstellar and intergalactic events as well as turbulence in Earth’s ionosphere.

ECE’s Steve Ellingson, Cameron Patterson and Majid Manteghi are working with researchers from the University of New Mexico, the U.S. Naval Research Laboratory, and NASA’s Jet Propulsion Laboratory to build a number of array stations distributed across New Mexico. Each station will consist of 256 pairs of dipole-like antennas that operate over the frequency range 10-88 MHz.

The outputs will be sent to a central location where they will be correlated to form images using aperture synthesis techniques. With an estimated image sensitivity of a few millijanskys (1 millijansky equals 10- 29 watts per square meter per hertz), the angular resolution and sensitivity of the LWA should be comparable to existing instruments operating at shorter wavelengths.

Existing arrays built on previous technology are very narrowband, whereas LWA is very broadband, Ellingson noted. “That’s enabled by a better antenna design combined with better analog electronics,” he added.

The team’s goal is to build 53 array stations, but to date, two stations have been funded and funding is projected for two more. Virginia Tech’s team, which built and operated a similar, but smaller, telescope near Asheville, N.C., is focusing on the LWA’s calibration, data recording, transient detection, and monitoring and control systems.