eCite Digital Repository

Surveying the Dynamic Radio Sky with the Long Wavelength Demonstrator Array


Lazio, TJW and Clarke, TE and Lane, WM and Gross, C and Kassim, NE and Ray, PS and Wood, D and York, JA and Kerkhoff, A and Hicks, B and Polisensky, E and Stewart, K and Dalal, NP and Cohen, AS and Erickson, WC, Surveying the Dynamic Radio Sky with the Long Wavelength Demonstrator Array, Astronomical Journal, 140, (6) pp. 1995-2006. ISSN 0004-6256 (2010) [Refereed Article]

DOI: doi:10.1088/0004-6256/140/6/1995


This paper presents a search for radio transients at a frequency of 73.8 MHz (4 m wavelength) using the all-sky imaging capabilities of the Long Wavelength Demonstrator Array (LWDA). The LWDA was a 16-dipole phased array telescope, located on the site of the Very Large Array in New Mexico. The field of view of the individual dipoles was essentially the entire sky, and the number of dipoles was sufficiently small that a simple software correlator could be used to make all-sky images. From 2006 October to 2007 February, we conducted an all-sky transient search program, acquiring a total of 106 hr of data; the time sampling varied, being 5 minutes at the start of the program and improving to 2 minutes by the end of the program. We were able to detect solar flares, and in a special-purpose mode, radio reflections from ionized meteor trails during the 2006 Leonid meteor shower. We detected no transients originating outside of the solar system above a flux density limit of 500 Jy, equivalent to a limit of no more than about 10(-2) events yr(-1) deg(-2), having a pulse energy density greater than or similar to 1.5 x 10(-20) J m(-2) Hz(-1) at 73.8 MHz for pulse widths of about 300 s. This event rate is comparable to that determined from previous all-sky transient searches, but at a lower frequency than most previous all-sky searches. We believe that the LWDA illustrates how an all-sky imaging mode could be a useful operational model for low-frequency instruments such as the Low Frequency Array, the Long Wavelength Array station, the low-frequency component of the Square Kilometre Array, and potentially the Lunar Radio Array.

Item Details

Item Type:Refereed Article
Keywords:instrumentation: interferometers; methods: observational; radio continuum: general
Research Division:Physical Sciences
Research Group:Astronomical sciences
Research Field:Astronomical instrumentation
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the physical sciences
UTAS Author:Erickson, WC (Professor William Erickson)
ID Code:70494
Year Published:2010
Web of Science® Times Cited:36
Deposited By:Research Division
Deposited On:2011-06-23
Last Modified:2011-06-23

Repository Staff Only: item control page