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arXiv · 1410.7422

Pulsar Observations Using the First Station of the Long Wavelength Array and the LWA Pulsar Data Archive

Abstract

We present initial pulsar results from the first station of the Long Wavelength Array (LWA1) obtained during the commissioning period of LWA1 and early science results. We present detections of periodic emission from 44 previously known pulsars, including 3 millisecond pulsars (MSPs). The effects of the interstellar medium on pulsar emission are significantly enhanced at the low frequencies of the LWA1 band (10--88 MHz), making LWA1 a very sensitive instrument for characterizing changes in dispersion measures (DM) and other effects from the interstellar medium. Pulsars also often have significant evolution in their pulse profile at low frequency and a break in their spectral index. We report DM measurements for 44 pulsars, mean flux density measurements for 36 pulsars, and multi-frequency component spacing and widths for 15 pulsars with more than one profile component. For 27 pulsars, we report spectral index measurements within our frequency range. We also introduce the LWA1 Pulsar Data Archive, which stores reduced data products from LWA1 pulsar observations. Reduced data products for the observations presented here can be found on the archive. Reduced data products from future LWA1 pulsar observations will also be made available through the archive.

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K. Stovall, P. S. Ray, J. Blythe, J. Dowell, T. Eftekhari, A. Garcia, T. J. W. Lazio, M. McCrackan, F. K. Schinzel, G. B. Taylor. 2014-10-27. Pulsar Observations Using the First Station of the Long Wavelength Array and the LWA Pulsar Data Archive. https://doi.org/10.1088/0004-637x/808/2/156

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