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Related papers: Turn-over in pulsar spectra around 1 GHz

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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…

Astrophysics · Physics 2007-05-23 J. Kijak , Y. Gupta , K. Krzeszowski

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…

Astrophysics of Galaxies · Physics 2011-06-30 J. Kijak , W. Lewandowski , O. Maron , Y. Gupta , A. Jessner

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…

Astrophysics · Physics 2009-11-13 O. Loehmer , A. Jessner , M. Kramer , R. Wielebinksi , O. Maron

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…

High Energy Astrophysical Phenomena · Physics 2015-11-11 Kaustubh Rajwade , Duncan R Lorimer , Loren D Anderson

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…

High Energy Astrophysical Phenomena · Physics 2017-05-24 J. Kijak , R. Basu , W. Lewandowski , K. Rozko , M. Dembska

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…

High Energy Astrophysical Phenomena · Physics 2025-04-14 K. Rożko , J. Kijak , R. Basu , P. Dabhade , W. Lewandowski

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…

High Energy Astrophysical Phenomena · Physics 2022-01-11 K. Rożko , R. Basu , J. Kijak , W. Lewandowski

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…

Astrophysics · Physics 2009-10-31 Olaf Maron , Jaroslaw Kijak , Michael Kramer , Richard Wielebinski

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…

Astrophysics · Physics 2007-05-23 A. von Hoensbroech , J. Kijak , A. Krawczyk

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…

High Energy Astrophysical Phenomena · Physics 2018-06-29 Pablo Torne

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…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Asuka Ito , Kazunori Kohri , Kazunori Nakayama

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…

High Energy Astrophysical Phenomena · Physics 2016-02-22 Rahul Basu , Karolina Rożko , Wojciech Lewandowski , Jarosław Kijak , Marta Dembska

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…

Astrophysics of Galaxies · Physics 2015-08-26 M. Kuniyoshi , J. P. W. Verbiest , K. J. Lee , B. Adebahr , M. Kramer , A. Noutsos

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…

Solar and Stellar Astrophysics · Physics 2015-06-15 O. Maron , M. Serylak , J. Kijak , K. Krzeszowski , D. Mitra , A. Jessner

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…

High Energy Astrophysical Phenomena · Physics 2022-05-11 B. Shaw , B. W. Stappers , P. Weltevrede , P. R. Brook , A. Karastergiou , C. A. Jordan , M. J. Keith , M. Kramer , A. G. Lyne

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…

High Energy Astrophysical Phenomena · Physics 2014-10-31 M. Dembska , J. Kijak , A. Jessner , W. Lewandowski , B. Bhattacharyya , Y. Gupta

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…

Solar and Stellar Astrophysics · Physics 2015-06-15 Samuel D. Bates , Duncan R. Lorimer , Joris P. W. Verbiest

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.…

Astrophysics · Physics 2009-10-31 M. Kramer , C. Lange , D. R. Lorimer , D. C. Backer , K. M. Xilouris , A. Jessner , R. Wielebinski

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…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Wojciech Lewandowski , Marta Dembska , Jaroslaw Kijak , Magdalena Kowalinska
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