Imaging at Both Ends of the Spectrum: the Long Wavelength Array and Fermi

TL;DR

The paper discusses the Long Wavelength Array (LWA), a new radio telescope operating at 10-88 MHz, which complements Fermi by enabling studies of astrophysical phenomena like AGN, pulsars, and the dark ages through high-resolution imaging and spectral analysis.

Contribution

It introduces the LWA's design, capabilities, and its potential for multi-wavelength astrophysical studies in conjunction with Fermi observations.

Findings

LWA can image the sky with a few arcseconds resolution at 20-80 MHz.

First LWA station, LWA1, enables spectral studies of AGN radio lobes.

LWA1 images the sky daily, complementing Fermi's observations.

Abstract

The Long Wavelength Array (LWA) will be a new multi-purpose radio telescope operating in the frequency range 10-88 MHz. Scientific programs include pulsars, supernova remnants, general transient searches, radio recombination lines, solar and Jupiter bursts, investigations into the "dark ages" using redshifted hydrogen, and ionospheric phenomena. Upon completion, LWA will consist of 53 phased array "stations" distributed across a region over 400 km in diameter. Each station consists of 256 pairs of dipole-type antennas whose signals are formed into beams, with outputs transported to a central location for high-resolution aperture synthesis imaging. The resulting image sensitivity is estimated to be a few mJy (5sigma, 8 MHz, 2 polarizations, 1 h, zenith) from 20-80 MHz; with angular resolution of a few arcseconds. Additional information is online at http://lwa.unm.edu. Partners in the LWA project include LANL, JPL, NRL, UNM, NMT, and Virginia Tech. The full LWA will be a powerful instrument for the study of particle acceleration mechanisms in AGN. Even with the recently completed first station of the LWA, called "LWA1", we can begin spectral studies of AGN radio lobes. These can be combined with Fermi observations. Furthermore we have an ongoing project to observe Crab Giant Pulses in concert with Fermi. In addition to these pointed studies, the LWA1 images the sky down to declination -30 degrees daily. This is quite complimentary to Fermi's daily images of the sky.