Results from multi-frequency observations of PSR B0826-34

TL;DR

This study presents multi-frequency observations of pulsar PSR B0826-34, revealing no weak emission during null states, broadband pulse correlations, and frequency-dependent drift patterns, along with an accurate dispersion measure estimate.

Contribution

It provides new insights into the broadband emission, null state behavior, and frequency evolution of pulse drift patterns in PSR B0826-34 using simultaneous multi-frequency data.

Findings

No weak emission detected during null states at all observed frequencies.

Significant correlation in pulse intensity between 303 and 610 MHz.

Drift band separation (P2) varies with frequency and pulse longitude.

Abstract

We report new results obtained from multi-frequency observations of PSR B0826-34 with the Giant Metrewave Radio Telescope (GMRT). (1) We find no evidence of weak emission during the typical long null state of this pulsar, simultaneously at 303 and 610 MHz, as well as individually at 157, 325, 610 and 1060 MHz at separate epochs. Our limit of non-detection is at ~ 1% or better of the peak of the active state profile, and corresponds to ~ 2 mJy at 610 MHz. (2) Significant correlation in the total intensity of the individual pulses between 303 and 610 MHz is reported from the simultaneous dual frequency observations, which is indicative of the broadband nature of the emission. We also report correlation between total energy in the main pulse and inter-pulse region from the high sensitivity single frequency observations at 610 and 1060 MHz. (3) Though we find the drift pattern to be very similar in the simultaneous 303 and 610 MHz data, we observe that the drift band separation (P2) evolves significantly between these two frequencies, and in a manner opposite to the average profile evolution. In addition, we confirm the dependence of P2 on pulse longitude at 303 MHz and find indications for the same at 610 MHz. We also present results for subpulse width at different frequencies, and as well as a function of pulse longitude. (4) As a natural out-come of the simultaneous dual frequency observations, we obtain an accurate DM value, equal to 52.2(6) pc/cc, for this pulsar.