相关论文: Turn-over in pulsar spectra around 1 GHz

We present the first direct evidence for turn-over in pulsar radio spectra at high frequencies. Two pulsars are now shown to have a turn-over frequency > 1GHz. We also find some evidence that the peak frequency of turn-over in pulsar…

We investigate a high frequency turn-over effect in radio spectra for pulsars with positive or flat spectral index. Using GMRT and Effelsberg observatory, we estimated the flux density to reconstruct pulsar spectra. We find objects that…

The behaviour of the pulsar spectrum at high radio frequencies can provide decisive information about the nature of the radio emission mechanism. We report recent observations of a selected sample of pulsars at lambda=9mm (32 GHz) with the…

Pulsars are known to emit non-thermal radio emission that is generally a power-law function of frequency. In some cases, a turnover is seen at frequencies around 100~MHz. Kijak et al. have reported the presence of a new class of ''Gigahertz…

We present the results of our radio interferometric observations of pulsars at 325 MHz and 610 MHz using the Giant Metrewave Radio Telescope (GMRT). We used the imaging method to estimate the flux densities of several pulsars at these radio…

We report the measurements of low radio frequency spectra of fourteen gigahertz-peaked spectra (GPS) pulsar candidates, between 300~MHz and 700~MHz, using the upgraded Giant Meterwave Radio Telescope. Combining newly collected measurements…

We report the detailed spectral measurements over a wide frequency range of three pulsars: J1741-3016, J1757-2223 and J1845-0743, using the Giant Metrewave Radio Telescope, which allowed us to identify them as a new gigahertz-peaked spectra…

We have collected pulsar flux density observations and compiled spectra of 281 objects. The database of Lorimer et al. (\cite{lorimer}) has been extended to frequencies higher than 1.4 GHz and lower than 300 MHz. Our results show that above…

We have analyzed the polarization properties of pulsars at an observing frequency of 4.9 GHz. Together with low frequency data, we are able to trace polarization profiles over more than three octaves into an interesting frequency regime. At…

Detecting and studying pulsars above a few GHz in the radio band is challenging due to the typical faintness of pulsar radio emission, their steep spectra, and the lack of observatories with sufficient sensitivity operating at high…

We study graviton-photon conversion in magnetosphere of a pulsar and explore the possibility of detecting high frequency gravitational waves with pulsar observations. It is shown that conversion of one polarization mode of photons can be…

We report the flux measurement of the Vela like pulsar B1800-21 at the low radio frequency regime over multiple epochs spanning several years. The spectrum shows a turnover around the GHz frequency range and represents a typical example of…

Measurements of pulsar flux densities are of great importance for understanding the pulsar emission mechanism and for predictions of pulsar survey yields and the pulsar population at large. Typically these flux densities are determined from…

Aims. To investigate the flux density modulation from pulsars and the existence of specific behaviour of modulation index versus frequency. Methods. Several pulsars have been observed with the Effelsberg radio telescope at 8.35 GHz. Their…

With the ever-increasing sensitivity and timing baselines of modern radio telescopes, a growing number of pulsars are being shown to exhibit transitions in their rotational and radio emission properties. In many of these cases, the two are…

In this paper we present results from flux density measurements for 21 pulsars over a wide frequency range, using the Giant Metrewave Radio Telescope (GMRT) and the Effelsberg telescope. Our sample was a set of mostly newly discovered…

The flux density spectra of radio pulsars are known to be steep and, to first order, described by a power-law relationship of the form S_{\nu} \propto \nu^{\alpha}, where S_{\nu} is the flux density at some frequency \nu and \alpha is the…

In this paper we present the first observations of a large sample of millisecond pulsars at frequencies of 2.7 GHz and 4.9 GHz. Our new flux measurements extend the known spectra for millisecond pulsars to the highest frequencies to date.…

Integrated pulse profiles at 8.6~GHz obtained with the Shanghai Tian Ma Radio Telescope (TMRT) are presented for a sample of 26 pulsars. Mean flux densities and pulse width parameters of these pulsars are estimated. For eleven pulsars these…

We show the results of our analysis of the pulse broadening phenomenon in 25 pulsars at several frequencies using the data gathered with GMRT and Effelsberg radiotelescopes. Twenty two of these pulsars were not studied in that regard before…