Law, C. J. and Jones, G. and Backer, D. C. and Barott, W. C. and Bower, G. C. and Gutierrez-Kraybill, C. and Williams, P. K. G. and Werthimer, D. (2011) Millisecond Imaging of Radio Transients with the Pocket Correlator. Astrophysical Journal, 742 (1). Art. No. 12. ISSN 0004-637X http://resolver.caltech.edu/CaltechAUTHORS:20111207-080944884
- Published Version
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20111207-080944884
We demonstrate a signal-processing concept for imaging the sky at millisecond rates with radio interferometers. The "Pocket Correlator" (PoCo) correlates the signals from multiple elements of a radio interferometer fast enough to image brief, dispersed pulses. By the nature of interferometry, a millisecond correlator functions like a large, single-dish telescope, but with improved survey speed, spatial localization, calibration, and interference rejection. To test the concept, we installed PoCo at the Allen Telescope Array (ATA) to search for dispersed pulses from the Crab pulsar, B0329+54, and M31 using total-power, visibility-based, and image-plane techniques. In 1.7 hr of observing, PoCo detected 191 giant pulses from the Crab pulsar brighter than a typical 5σ sensitivity limit of 60 Jy over pulse widths of 3 ms. Roughly 40% of pulses from pulsar B0329+54 were detected by using novel visibility-based techniques. Observations of M31 constrain the rate of pulses brighter than 190 Jy in a three-degree region surrounding the galaxy to <4.3 hr^(–1). We calculate the computational demand of various visibility-based pulse search algorithms and demonstrate how compute clusters can help meet this demand. Larger implementations of the fast imaging concept will conduct blind searches for millisecond pulses in our Galaxy and beyond, providing a valuable probe of the interstellar/intergalactic media, discovering new kinds of radio transients, and localizing them to constrain models of their origin.
|Additional Information:||© 2011 The American Astronomical Society. Received 2011 June 23; accepted 2011 August 10; published 2011 November 1. We thank the staff of the Radio Astronomy Lab, SETI Institute, and Hat Creek Radio Observatory for support and Matthew Bailes for comments. G.J. is supported by the NRAO, which is operated by Associated Universities, Inc., under cooperative agreement with the National Science Foundation. This research has made use of NASA’s Astrophysics Data System Bibliographic Services. The authors acknowledge the generous support of the Paul G. Allen Family Foundation that has provided major support for design, construction, and operations of the ATA. The US Naval Observatory provided significant funds for ATA construction. Contributions from Nathan Myhrvold, Xilinx Corporation, Sun Microsystems, and other private donors have been instrumental in supporting the ATA. The US National Science Foundation grants AST-0321309, AST-0540690, and AST-0838268 have contributed to the ATA project.|
|Subject Keywords:||galaxies: ISM; intergalactic medium; methods: data analysis; pulsars: individual (B0329+54, Crab); techniques: interferometric|
|Official Citation:||Millisecond Imaging of Radio Transients with the Pocket Correlator C. J. Law et al. 2011 ApJ 742 12|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Ruth Sustaita|
|Deposited On:||07 Dec 2011 16:32|
|Last Modified:||26 Dec 2012 14:34|
Repository Staff Only: item control page