Flux density measurements of gigahertz-peaked spectra candidate Pulsars at 610 MHz using an interferometric imaging technique

Abstract

We conducted radio interferometric observations of six pulsars at 610 MHz using the Giant Metrewave Radio Telescope. All these objects were claimed or suspected to be gigahertzpeaked spectra (GPS) pulsars. For half of the sources in our sample, interferometric imaging is the only way to estimate their flux at 610 MHz due to strong pulse scatter-broadening. In our case, these pulsars have very high dispersion measure values and we present their spectra with, for the first time, low-frequency measurements. The remaining three pulsars were observed at low frequencies using the conventional pulsar flux measurement method. The interferometric imaging technique allowed us to re-examine their fluxes at 610 MHz. We were able to confirm the GPS feature in the PSR B1823−13 spectrum and select a GPS candidate pulsar. These results clearly demonstrate that the interferometric imaging technique can be successfully applied to estimate the flux density of pulsars even in the presence of strong scattering.