Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/55689

Title

A CLEAN-based method for deconvolving interstellar pulse broadening from radio pulses

Author(s)

Bhat, N. D. R.;  Cordes, James M.;  Chatterjee, Soumya

Abstract

Multipath propagation in the interstellar medium distorts radio pulses, an effect predominant for distant pulsars observed at low frequencies. Typically, broadened pulses are analyzed to determine the amount of propagation-induced pulse broadening but with little interest in determining the undistorted pulse shapes. In this paper, we develop and apply a method that recovers both the intrinsic pulse shape and the pulse-broadening function that describes the scattering of an impulse. The method resembles the CLEAN algorithm used in synthesis imaging applications, although we search for the best pulse-broadening function and perform a true deconvolution to recover intrinsic pulse structure. As figures of merit to optimize the deconvolution, we use the positivity and symmetry of the deconvolved result along with the mean square residual and the number of points below a given threshold. Our method makes no prior assumptions about the intrinsic pulse shape and can be used for a range of scattering functions for the interstellar medium. It can therefore be applied to a wider variety of measured pulse shapes and degrees of scattering than the previous approaches. We apply the technique to both simulated data and data from Arecibo observations.

Publication type

Journal article

Source

Astrophysical Journal, Vol. 584, no. 2 (Feb 2003), pp. 782-790

Publication year

2003

FOR Code(s)

0201 Astronomical and Space Sciences

Keyword(s)

Data analysis methods;  ISM structure;  Pulsars;  Radio continuum;  Scattering

Publisher

University of Chicago Press

ISSN

0004-637X

Publisher URL

http://dx.doi.org/10.1086/345775

Copyright

Copyright © 2003. The American Astronomical Society. All rights reserved.

Peer reviewed