Related papers: Observing pulsars and fast transients with LOFAR
Traditional radio telescopes use large, steel dishes to observe radio sources. The LOFAR radio telescope is different, and uses tens of thousands of fixed, non-movable antennas instead, a novel design that promises ground-breaking research…
We report the detection of 48 millisecond pulsars (MSPs) out of 75 observed thus far using the LOFAR in the frequency range 110-188 MHz. We have also detected three MSPs out of nine observed in the frequency range 38-77 MHz. This is the…
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…
Deep radio observations of galaxy clusters have revealed the existence of diffuse radio sources related to the presence of relativistic electrons and weak magnetic fields in the intracluster volume. The role played by this non-thermal…
The Lockman Hole is a well-studied extragalactic field with extensive multi-band ancillary data covering a wide range in frequency, essential for characterising the physical and evolutionary properties of the various source populations…
We have used LOFAR to perform targeted millisecond pulsar surveys of Fermi gamma-ray sources. Operating at a center frequency of 135 MHz, the surveys use a novel semi-coherent dedispersion approach where coherently dedispersed trials at…
LOFAR is the LOw Frequency Radio interferometer ARray located at mid-latitude ($52^{\circ} 53'N$). Here, we present results on ionospheric structures derived from 29 LOFAR nighttime observations during the winters of 2012/2013 and…
Radio astronomy has benefited greatly from advances in technology and will continue to do so in the future. In fact, we are experiencing a revolution in the way radio astronomy is conducted as our instruments allow us now to directly…
The Low Frequency Array (LOFAR) is uniquely able to perform deep, 15" resolutions imaging at frequencies below 100 MHz. Observations in this regime, using the Low Band Antenna (LBA) system, are significantly affected by instrumental and…
The motivation to build spaceborne interferometric arrays for low-frequency radio astronomy is widely recognised because frequencies below the ionospheric cutoff are inaccessible for ground-based radio telescopes. We discuss the theoretical…
Radio astronomy is entering a new era with new and future radio observatories such as the Low Frequency Array and the Square Kilometer Array. We describe in detail an automated flagging pipeline and evaluate its performance. With only a…
Relatively little information is available about the Universe at ultra-low radio frequencies, i.e. below 50 MHz (ULF), although the ULF spectral window contains a wealth of unique diagnostics for studying galactic and extragalactic…
Transient radio phenomena and pulsars are one of six LOFAR Key Science Projects (KSPs). As part of the Transients KSP, the Pulsar Working Group (PWG) has been developing the LOFAR Pulsar Data Pipelines to both study known pulsars as well as…
The Sun is an active star that often produces numerous bursts of electromagnetic radiation at radio wavelengths. Low frequency radio bursts have recently been brought back to light with the advancement of novel radio interferometers.…
When an ultra-high energy neutrino or cosmic ray strikes the Lunar surface a radio-frequency pulse is emitted. We plan to use the LOFAR radio telescope to detect these pulses. In this work we propose an efficient trigger implementation for…
Low-frequency radio astronomy is limited by severe ionospheric distortions below 50 MHz and complete reflection of radio waves below 10-30 MHz. Shielding of man-made interference from long-range radio broadcasts, strong natural radio…
The radio sky at lower frequencies, particularly below 20 MHz, is expected to be a combination of increasingly bright non-thermal emission and significant absorption from intervening thermal plasma. The sky maps at these frequencies cannot…
Ultra-high-energy neutrinos and cosmic rays produce short radio flashes through the Askaryan effect when they impact on the Moon. Earthbound radio telescopes can search the Lunar surface for these signals. A new generation of low-…
Regular magnetic field structures can be derived from the Faraday rotation measures (RM) of polarized background sources observable at 1.4 GHz with the SKA. At lower frequencies ($<250$ MHz) polarimetry of radio sources with the Low…
LOFAR is a new and innovative effort to build a radio-telescope operating at the multi-meter wavelength spectral window. One of the most exciting applications of LOFAR will be the search for redshifted 21-cm line emission from the Epoch of…