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Title: MULTIMOMENT RADIO TRANSIENT DETECTION

Abstract

We present a multimoment technique for signal classification and apply it to the detection of fast radio transients in incoherently dedispersed data. Specifically, we define a spectral modulation index in terms of the fractional variation in intensity across a spectrum. A signal whose intensity is distributed evenly across the entire band has a lower modulation index than a spectrum whose intensity is localized in a single channel. We are interested in broadband pulses and use the modulation index to excise narrowband radio frequency interference by applying a modulation index threshold above which candidate events are removed. The technique is tested both with simulations and using data from known sources of radio pulses (RRAT J1928+15 and giant pulses from the Crab pulsar). The method is generalized to coherent dedispersion, image cubes, and astrophysical narrowband signals that are steady in time. We suggest that the modulation index, along with other statistics using higher order moments, should be incorporated into signal detection pipelines to characterize and classify signals.

Authors:
; ;  [1];  [2]
  1. Astronomy Department and NAIC, Cornell University, Ithaca, NY 14853 (United States)
  2. Department of Physics and Astronomy, Barnard College, New York, NY 10027 (United States)
Publication Date:
OSTI Identifier:
22016135
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 748; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; COMPUTERIZED SIMULATION; DATA ANALYSIS; INTERFERENCE; PULSARS

Citation Formats

Spitler, L. G., Cordes, J. M., Chatterjee, S., and Stone, J., E-mail: lspitler@astro.cornell.edu. MULTIMOMENT RADIO TRANSIENT DETECTION. United States: N. p., 2012. Web. doi:10.1088/0004-637X/748/2/73.
Spitler, L. G., Cordes, J. M., Chatterjee, S., & Stone, J., E-mail: lspitler@astro.cornell.edu. MULTIMOMENT RADIO TRANSIENT DETECTION. United States. doi:10.1088/0004-637X/748/2/73.
Spitler, L. G., Cordes, J. M., Chatterjee, S., and Stone, J., E-mail: lspitler@astro.cornell.edu. 2012. "MULTIMOMENT RADIO TRANSIENT DETECTION". United States. doi:10.1088/0004-637X/748/2/73.
@article{osti_22016135,
title = {MULTIMOMENT RADIO TRANSIENT DETECTION},
author = {Spitler, L. G. and Cordes, J. M. and Chatterjee, S. and Stone, J., E-mail: lspitler@astro.cornell.edu},
abstractNote = {We present a multimoment technique for signal classification and apply it to the detection of fast radio transients in incoherently dedispersed data. Specifically, we define a spectral modulation index in terms of the fractional variation in intensity across a spectrum. A signal whose intensity is distributed evenly across the entire band has a lower modulation index than a spectrum whose intensity is localized in a single channel. We are interested in broadband pulses and use the modulation index to excise narrowband radio frequency interference by applying a modulation index threshold above which candidate events are removed. The technique is tested both with simulations and using data from known sources of radio pulses (RRAT J1928+15 and giant pulses from the Crab pulsar). The method is generalized to coherent dedispersion, image cubes, and astrophysical narrowband signals that are steady in time. We suggest that the modulation index, along with other statistics using higher order moments, should be incorporated into signal detection pipelines to characterize and classify signals.},
doi = {10.1088/0004-637X/748/2/73},
journal = {Astrophysical Journal},
number = 2,
volume = 748,
place = {United States},
year = 2012,
month = 4
}
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