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Related papers: New results from LOFAR

200 papers

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

Searches for millisecond-duration, dispersed single pulses have become a standard tool used during radio pulsar surveys in the last decade. They have enabled the discovery of two new classes of sources: rotating radio transients and fast…

Instrumentation and Methods for Astrophysics · Physics 2018-08-17 D. Michilli , J. W. T. Hessels , R. J. Lyon , C. M. Tan , C. Bassa , S. Cooper , V. I. Kondratiev , S. Sanidas , B. W. Stappers , J. van Leeuwen

Faraday rotation measurements using the current and next generation of low-frequency radio telescopes will provide a powerful probe of astronomical magnetic fields. However, achieving the full potential of these measurements requires…

The active broadband (1 kHz-100 MHz) tripole antenna now envisaged to be placed on the European Lunar Lander located at the Lunar South Pole allows for sensitive measurements of the exosphere and ionosphere, and their interaction with the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Marc Klein Wolt , Amin Aminaei , Philippe Zarka , Jan-Rutger Schrader , Albert-Jan Boonstra , Heino Falcke

Neutron stars that show X-ray and $\gamma$-ray pulsed emission must, somewhere in the magnetosphere, generate electron-positron pairs. Such pairs are also required for radio emission, but then why do a number of these sources appear radio…

High Energy Astrophysical Phenomena · Physics 2023-04-19 Inés Pastor-Marazuela , Samayra M. Straal , Joeri van Leeuwen , Vlad I. Kondratiev

The electromagnetic counterparts to gravitational wave (GW) merger events are highly sought after, but difficult to find owing to large localization regions. In this study, we present a strategy to search for compact object merger radio…

High Energy Astrophysical Phenomena · Physics 2021-11-10 K. Gourdji , A. Rowlinson , R. A. M. J. Wijers , J. W. Broderick , A. Shulevski , P. G. Jonker

We present low-frequency spectral energy distributions of 60 known radio pulsars observed with the Murchison Widefield Array (MWA) telescope. We searched the GaLactic and Extragalactic All-sky MWA (GLEAM) survey images for 200-MHz continuum…

It has long been known that luminous, ultra-steep spectrum radio sources are preferentially associated with massive galaxies at high redshifts. Here we describe a pilot project directed at such objects, to demonstrate the feasibility and…

Astrophysics of Galaxies · Physics 2023-08-02 C. M. Cordun , R. Timmerman , G. K. Miley , R. J. van Weeren , F. Sweijen , L. K. Morabito , H. J. A. Röttgering

We present the astrometric identification of 80 known radio pulsars as unresolved continuum sources detected at 144 MHz in the second data release of the LOFAR Two-metre Sky Survey (LoTSS DR2), which covers 27% of the Northern hemisphere.…

High Energy Astrophysical Phenomena · Physics 2026-02-18 G. A. C. Rijkers , C. G. Bassa , J. R. Callingham , T. Shimwell

The majority of searches for radio emission from exoplanets have to date focused on short period planets, i.e., the so-called hot Jupiter type planets. However, these planets are likely to be tidally locked to their host stars and may not…

Earth and Planetary Astrophysics · Physics 2018-05-02 Eamon O'Gorman , Colm P. Coughlan , Wouter Vlemmings , Eskil Varenius , Sandeep Sirothia , Tom P. Ray , Hans Olofsson

Cosmic particles hitting Earth's moon produce radio emission via the Askaryan effect. If the resulting radio ns-pulse can be detected by radio telescopes, this technique potentially increases the available collective area for ZeV scale…

Pulsars can be used to search for stochastic backgrounds of gravitational waves of cosmological origin within the very low frequency band (VLF), $10^{-7}$ to $10^{-9}$ Hz. We propose to construct a special 50 m radio telescope. Regular…

Astrophysics · Physics 2008-11-26 Shou-Guan Wang , Zong-Hong Zhu , Zhen-Long Zou , Yuan-Zhong Zhang

Blazars are powerful, variable emitters from radio to gamma-ray wavelengths. Even though the general picture of synchrotron emission at low energies and inverse Compton at the high energy end is well established, many important aspects of…

High Energy Astrophysical Phenomena · Physics 2019-08-15 W. Max-Moerbeck , J. L. Richards , V. Pavlidou , T. J. Pearson , A. C. S. Readhead , T. Hovatta , O. G. King , R. Reeves

Faraday tomography, the study of the distribution of extended polarized emission by strength of Faraday rotation, is a powerful tool for studying magnetic fields in the interstellar medium of our Galaxy and nearby galaxies. The strong…

Astrophysics of Galaxies · Physics 2018-10-24 Cameron L. Van Eck

We have used sensitive LOw Frequency ARray (LOFAR) observations of PSR B0809+74 at 15--62 MHz to study the anomalously intensive pulses, first reported by Ulyanov et al. (2006) at 18--30MHz. Similarly to Ulyanov et al., we found that the…

High Energy Astrophysical Phenomena · Physics 2018-08-22 X. Song , V. I. Kondratiev , A. V. Bilous

Cosmic-ray air shower detection with the low-frequency part of the Square Kilometre Array (SKA) radio telescope is envisioned to yield very high precision measurements of the particle composition of cosmic rays between $10^{16}$ and…

High Energy Astrophysical Phenomena · Physics 2025-06-24 A. Corstanje , S. Buitink , S. Bouma , M. Desmet , J. R. Hörandel , T. Huege , P. Laub , K. Mulrey , A. Nelles , O. Scholten , K. Terveer , S. Thoudam , K. Watanabe

We use recent population synthesis results to investigate the distribution of pulsars in the frequency space, having a gravitational strain high enough to be detected by the future generations of laser beam interferometers. We find that…

Astrophysics · Physics 2008-11-26 Tania Regimbau , Jose Antonio de Freitas Pacheco