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Related papers: Finding pulsars with LOFAR

200 papers

We have used the Effelsberg 100-m radio telescope to conduct a 1400-MHz ($\lambda$ 21-cm) search for young and rapidly rotating radio pulsars along a 2 deg$^2$ strip of the northern Galactic plane defined by $28^{\circ} \leq l \leq…

Astrophysics · Physics 2007-05-23 D. R. Lorimer , M. Kramer , P. Mueller , N. Wex , A. Jessner , C. Lange , R. Wielebinski

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

Searches for millisecond pulsars (which we here loosely define as those with periods $<$ 20 ms) in the Galactic field have undergone a renaissance in the past five years. New or recently refurbished radio telescopes utilizing cooled…

Astrophysics of Galaxies · Physics 2015-06-16 K. Stovall , D. R. Lorimer , R. S Lynch

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…

Pulsar timing is a foundational part of pulsar research to triage the most interesting systems and to characterise properties (rotational or otherwise) of the population of these extreme objects. Due to the efficiency of a number of…

High Energy Astrophysical Phenomena · Physics 2026-05-25 D. J. McKenna , E. F. Keane , P. T. Gallagher , J. McCauley

The LOFAR Tied-Array All-Sky Survey (LOTAAS) is the most sensitive untargeted radio pulsar survey performed at low radio frequencies (119--151\,MHz) to date and has discovered 76 new radio pulsars, among which the 23.5-s pulsar J0250+5854,…

On the Large Phased Array (LPA) of Lebedev Physics Institute (LPI), a search for pulsars outside the Galaxy plane was carried out in a 300 sq. deg area. The search with a sensitivity 5-10 times better than that of previously conducted…

High Energy Astrophysical Phenomena · Physics 2023-05-03 S. A. Tyul'bashev , G. E. Tyul'basheva

Image-based searches have become a complementary approach for identifying pulsars, particularly at MHz frequencies where scattering and high dispersion measures affect high-time resolution observations. In this work, we searched the…

Astrophysics of Galaxies · Physics 2025-09-04 Silvia Mantovanini , N. Hurley-Walker , G. Anderson , K. Ross , S. W. Duchesne , T. J. Galvin

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…

Low frequency radio waves, while challenging to observe, are a rich source of information about pulsars. The LOw Frequency ARray (LOFAR) is a new radio interferometer operating in the lowest 4 octaves of the ionospheric "radio window":…

With LOFAR beginning operation in 2008 there is huge potential for studying pulsars with high signal to noise at low frequencies. We present results of observations made with the Westerbork Synthesis Radio Telescope to revisit, with modern…

Astrophysics · Physics 2009-11-13 B. W. Stappers , R. Karuppusamy , J. W. T. Hessels

The LOw-Frequency ARray (LOFAR) has recently conducted a survey (LOFAR Tied-Array All-sky Survey; LOTAAS) for pulsars in the Northern hemisphere that resulted in discoveries of 73 new pulsars. For the purpose of studying the properties of…

High Energy Astrophysical Phenomena · Physics 2021-05-05 Qi-Wei Lu , Zhong-Xiang Wang , Yi Xing

Among the current sample of over 2000 radio pulsars known primarily in the disk of our Galaxy, millisecond pulsars now number almost 200. Due to the phenomenal success of blind surveys of the Galactic field, and targeted searches of Fermi…

Astrophysics of Galaxies · Physics 2015-06-11 Duncan R. Lorimer

Pulsars are arguably the only astrophysical sources whose emission spans the entire electromagnetic spectrum, from decameter radio wavelengths to TeV energies. The LOw Frequency ARray (LOFAR) offers the unique possibility to study pulsars…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Vladislav Kondratiev , the LOFAR Pulsar Working Group

We have surveyed all 22 known Galactic globular clusters observable with the Arecibo radio telescope and within 70kpc of the Sun for radio pulsations at ~1.4GHz. Data were taken with the Wideband Arecibo Pulsar Processor, which provided the…

Astrophysics · Physics 2009-11-13 J. W. T. Hessels , S. M. Ransom , I. H. Stairs , V. M. Kaspi , P. C. C. Freire

We are conducting deep searches for radio pulsations at L-band (~ 20cm) towards more than 30 globular clusters using the 305m Arecibo telescope in Puerto Rico and the 100m Green Bank Telescope in West Virginia. With roughly three quarters…

We present first results from a LOFAR census of non-recycled pulsars. The census includes almost all such pulsars known (194 sources) at declinations ${\rm Dec}> 8^\circ$ and Galactic latitudes $|{\rm Gb}| > 3^\circ$, regardless of their…

LOFAR offers the unique capability of observing pulsars across the 10-240 MHz frequency range with a fractional bandwidth of roughly 50%. This spectral range is well-suited for studying the frequency evolution of pulse profile morphology…

Pulsars with periods more than 0.4 seconds in the declination range -9o < decj < 42o and in the right ascension range 0h < r.a.< 24h were searched in parallel with the program of interplanetary scintillations monitoring of a large number of…

We are performing two complementary pilot pulsar surveys as part of LOFAR commissioning. The LOFAR Pilot Pulsar Survey (LPPS) is a shallow all-sky survey using an incoherent combination of LOFAR stations. The LOFAR Tied-Array Survey (LOTAS)…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Thijs Coenen , The LOFAR Pulsar Working Group