Pulsars with gigahertz-peaked spectra

Abstract

Aims: We investigate a high frequency turn-over effect in radio spectra for pulsars with positive or flat spectral index. Methods. Using GMRT and Effelsberg observatory, we estimated the flux density to reconstruct pulsar spectra. Results. We find objects that have a maximum flux in their spectrum above 1 GHz, whose emitted energy decreases below 1 GHz and whose spectral indices are positive at lower frequencies. Some pulsars with a turn-over in their spectrum at high frequencies are found to exist in very interesting environments. We call these objects gigahertz-peaked spectra pulsars.