Flux density variability of 286 radio pulsars from a decade of monitoring

Abstract

The Parkes telescope has been monitoring 286 radio pulsars approximately monthly since 2007 at an observing frequency of 1.4 GHz. The wide dispersion measure (DM) range of the pulsar sample and the uniformity of the observing procedure make the data-set extremely valuable for studies of flux density variability and the interstellar medium. Here, we present flux density measurements and modulation indices of these pulsars over this period. We derive the structure function from the light curves and discuss the contributions to it from measurement noise, intrinsic variability and interstellar scintillation. Despite a large scatter, we show that the modulation index is inversely correlated with DM, and can be generally described by a power-law with an index of $\sim -0.7$ covering DMs from $\sim 10$ to 1000 cm${}^{-3}$ pc. We present refractive timescales and/or lower limits for a group of 42 pulsars. These often have values significantly different from theoretical expectations, indicating the complex nature of the interstellar medium along individual lines of sight. In particular, local structures and non-Kolmogorov density fluctuations are likely playing important roles in the observed flux density variation of many of these pulsars.

27 pages, 46 figures, accepted for publication in MNRAS

References in corpus (13)

• The ATNF Pulsar Catalogue
• The Parkes multibeam pulsar survey: VI. Discovery and timing of 142 pulsars and a Galactic population analysis
• Pulsar Nulling and Mode Changing
• An ultra-wide bandwidth (704 to 4032 MHz) receiver for the Parkes radio telescope
• Dispersion Measure Variations and their Effect on Precision Pulsar Timing
• Polarimetry of 600 pulsars from observations at 1.4 GHz with the Parkes radio telescope
• The Parkes Pulsar Timing Array Project: Second data release
• Scattering analysis of LOFAR pulsar observations
• Scatter broadening of pulsars and implications on the interstellar medium turbulence
• Modelling annual and orbital variations in the scintillation of the relativistic binary PSR J1141$-$6545
• Extreme Scattering Events Towards Two Young Pulsars
• Mode switching and oscillations in PSR B1828-11
• Flux density measurements for 32 pulsars in the 20 cm band

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• Two years of pulsar observations with the Ultra-Wideband Receiver on the Parkes radio telescope
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• Searching for pulsars associated with polarised point sources using LOFAR: Initial discoveries from the TULIPP project
• Flux density monitoring of 89 millisecond pulsars with MeerKAT
• Detection of strong scattering close to the eclipse region of PSR B1957+20
• The Thousand-Pulsar-Array programme on MeerKAT VII: Polarisation properties of pulsars in the Magellanic Clouds
• Flux Density Stability and Temporal Changes in the Spectra of Millisecond Pulsars using the GMRT
• The ASKAP Variables and Slow Transients (VAST) Pilot Survey
• Pulsar Polarization Array Limits on Ultralight Axion-like Dark Matter
• Intra-pulse variability induced by plasmoid formation in pulsar magnetospheres
• Study of pulsar flux density and its variability with Parkes data archive
• Ultra-wide Bandwidth Observations of 19 pulsars with Parkes telescope
• A study of 10 Rotating Radio Transients using Parkes radio telescope