S2DFS: Analysis of temporal changes of drifting subpulses

Abstract

We introduce a new technique, called the Sliding Two-Dimensional Fluctuation Spectrum, used for detecting and characterising the temporal changes of drifting subpulses from radio pulsars. The method was tested using simulated data as well as archived observations made with the WSRT at wavelengths of 92 and 21 cm. The drifting subpulse phenomenon is a well known property of radio pulsars. However the properties of the temporal behaviour of drifting subpulses are not fully explored. The drifting can also be non-coherent and the presence of effects like nulling or drift rate changing can mask the drifting behaviour of the pulsar. The S2DFS is a robust method for investigating this phenomenon and by introducing it we aim to expand our knowledge of the temporal drifting subpulse properties. Our new analysis method uses horizonally collapsed fluctuation spectra obtained with the Two-Dimensional Fluctuation Spectrum method. Stacking the collapsed spectra obtained in a 256 pulse window which slides by a pulse at a time produces a map of the collapsed fluctuation spectrum. By analysing the maps one can easily determine the presence of any temporal drift changes. Simulated data showed that the technique can reveal the presence of any temporal changes in drift behaviour like mode changing or nulling. We have also analysed data of three pulsars, PSRs B0031-07, B1819-22 and B1944+17, which were selected based on the quality of the data and their known drift properties. All three sources are known to exhibit mode changes which could easily be seen in the S2DFS. The results from the analysis of the data sets used in this paper have shown that the S2DFS method is robust and complimentary to the 2DFS method in detecting and characterising the temporal changes in drifting subpulses from radio pulsars.

accepted for publication in A&A, 10 pages, 7 figures, 1 table

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Cited by in corpus (14)

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• Meterwavelength Single-pulse Polarimetric Emission Survey II: The phenomenon of Drifting Subpulses
• Low Frequency Observations of the Subpulse Drifter PSR J0034-0721 with the Murchison Widefield Array
• Subpulse Drifting, Nulling and Mode changing in PSR J1822$-$2256
• Variability, polarimetry, and timing properties of single pulses from PSR J1713+0747 using the Large European Array for Pulsars
• A low frequency study of PSRs B1133+16, B1112+50, and B0031-07
• Phase-locked modulation delay between the poles of pulsar B1055-52
• Inter-relationship between the Two Emission Cones of B1237+25
• Revisiting the sub-pulse drifting phenomenon in PSR J1822-2256: Drift Modes, Sparks, and Emission Heights
• Simultaneous multi-frequency single pulse observations of pulsars
• Single pulse modeling and the bi-drifting subpulses of radio pulsar B1839-04
• MeerKAT observations of the reversing drifting subpulses in PSR J1750-3503
• Detection of long nulls in PSR B1706$-$16, a pulsar with large timing irregularities
• Variations of $P_2$ in subpulse drifting pulsars