Please use this identifier to cite or link to this item: http://hdl.handle.net/2289/6379
 Title: Simultaneous observations of giant pulses from the crab pulsar, with the Murchison widefield array and Parkes radio telescope: implications for the giant pulse emission mechanism. Authors: Oronsaye, S. L.Deshpande, A.A.Prabhu, T.Udaya Shankar, N.Srivani, K.S.Subrahmanyan, Ravi+20 Co-authors Issue Date: 10-Aug-2015 Publisher: IOP Sciences for The American Astronomical Society Citation: The Astrophysical Journal, 2015, Vol. 809, p51 Abstract: We report on observations of giant pulses from the Crab pulsar performed simultaneously with the Parkes radio telescope and the incoherent combination of the Murchison Widefield Array (MWA) antenna tiles. The observations were performed over a duration of approximately one hour at a center frequency of 1382 MHz with 340 MHz bandwidth at Parkes, and at a center frequency of 193 MHz with 15 MHz bandwidth at the MWA. Our analysis has led to the detection of 55 giant pulses at the MWA and 2075 at Parkes above a threshold of 3.5σ and 6.5σ, respectively. We detected 51% of the MWA giant pulses at the Parkes radio telescope, with spectral indices in the range of $-3.6\gt \alpha \gt -4.9$ (${S}_{\nu }\propto {\nu }^{\alpha }$). We present a Monte Carlo analysis supporting the conjecture that the giant pulse emission in the Crab is intrinsically broadband, the less than 100% correlation being due to the relative sensitivities of the two instruments and the width of the spectral index distribution. Our observations are consistent with the hypothesis that the spectral index of giant pulses is drawn from normal distribution of standard deviation 0.6, but with a mean that displays an evolution with frequency from −3.00 at 1382 MHz, to −2.85 at 192 MHz. Description: Restricted Access. An open-access version is available at arXiv.org (one of the alternative locations) URI: http://hdl.handle.net/2289/6379 ISSN: 0004-637X1538-4357-(Online) Alternative Location: http://adsabs.harvard.edu/abs/2015ApJ...809...51Ohttp://arxiv.org/abs/1507.04830http://dx.doi.org/10.1088/0004-637X/809/1/51 Copyright: 2015 American Astronomical Society Appears in Collections: Research Papers (A&A)

Files in This Item:
File Description SizeFormat
2015_APJ_809_51.pdf
Restricted Access