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Abstract A small number of pulsars are known to emit giant pulses (GPs), single pulses much brighter than average. Among these is PSR J0534+2200, also known as the Crab pulsar, a young pulsar with high GP rates. Long-term monitoring of the Crab pulsar presents an excellent opportunity to perform statistical studies of its GPs and the processes affecting them, potentially providing insight into the behavior of other neutron stars that emit bright single pulses. Here, we present an analysis of a set of 24,985 Crab GPs obtained from 88 hr of daily observations at a center frequency of 1.55 GHz by the 20 m telescope at the Green Bank Observatory, spread over 461 days. We study the effects of refractive scintillation at higher frequencies than previous studies and compare methods of correcting for this effect. We also search for deterministic patterns seen in other single-pulse sources, possible periodicities seen in several rotating radio transients and fast radio bursts, and clustering of GPs like that seen in the repeating fast radio burst FRB 121102.
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Single-pulse studies of three millisecond pulsars
Abstract Single-pulse studies are important to understand the pulsar emission mechanism and the noise floor in precision timing. We study total intensity and polarimetry properties of three bright millisecond pulsars – PSRs J1022+1001, J1713+0747, and B1855+09 – that have detectable single pulses at multiple frequencies. We report for the first time the detection of single pulses from PSRs J1022+1001 and J1713+0747 at 4.5 GHz. In addition, for those two pulsars, the fraction of linear polarization in the average profile is significantly reduced at 4.5 GHz, compared to 1.38 GHz, which could support the expected deviation from a dipolar field closer to the pulsar surface. There is a hint of orthogonal modes in the single pulses of PSR J1713+0747. More sensitive multifrequency observations may be useful to confirm these findings. The jitter noise contributions at 1.38 GHz, scaled to one hour, for PSRs J1022+1001, J1713+0747, and B1855+09 are ≈135, ≈45, and ≈60 ns, respectively and are consistent with previous studies. We also show that selective bright-pulse timing of PSR J1022+1001 yields improved root-mean-square residuals of ≈22 $$\mu$$s, which is a factor of ≈3 better than timing using single pulses alone.
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- Award ID(s):
- 2020265
- PAR ID:
- 10396973
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 520
- Issue:
- 2
- ISSN:
- 0035-8711
- Format(s):
- Medium: X Size: p. 2747-2756
- Size(s):
- p. 2747-2756
- Sponsoring Org:
- National Science Foundation
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