Searching for pulsars associated with polarised point sources using LOFAR: Initial discoveries from the TULIPP project

Abstract

Discovering radio pulsars, particularly millisecond pulsars (MSPs), is important for a range of astrophysical applications, such as testing theories of gravity or probing the magneto-ionic interstellar medium. We aim to discover pulsars that may have been missed in previous pulsar searches by leveraging known pulsar observables (primarily polarisation) in the sensitive, low-frequency radio images from the Low-Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS), and have commenced the Targeted search, using LoTSS images, for polarised pulsars (TULIPP) survey. For this survey, we identified linearly and circularly polarised point sources with flux densities brighter than 2 mJy in LoTSS images at a centre frequency of 144 MHz with a 48 MHz bandwidth. Over 40 known pulsars, half of which are MSPs, were detected as polarised sources in the LoTSS images and excluded from the survey. We have obtained beam-formed LOFAR observations of 30 candidates, which were searched for pulsations using coherent de-dispersion. Here, we present the results of the first year of the TULIPP survey. We discovered two pulsars, PSRs J1049+5822 and J1602+3901, with rotational periods of P=0.73 s and 3.7 ms, respectively. We also detected a further five known pulsars (two slowly-rotating pulsars and three MSPs) for which accurate sky positions were not available to allow a unique cross-match with LoTSS sources. This targeted survey presents a relatively efficient method by which pulsars, particularly MSPs, may be discovered using the flexible observing modes of sensitive radio telescopes such as the Square Kilometre Array and its pathfinders/precursors, particularly since wide-area all-sky surveys using coherent de-dispersion are currently computationally infeasible.

arXiv comment15 pages, 7 figures, 3 tables. Accepted for publication in A&A

References in corpus (122)

• Array Programming with NumPy
• Astropy: A Community Python Package for Astronomy
• Gaia Data Release 2. Summary of the contents and survey properties
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• Shapiro delay measurement of a two solar mass neutron star
• A Massive Pulsar in a Compact Relativistic Binary
• Binary companions of evolved stars in APOGEE DR14: Search method and catalog of ~5,000 companions
• The ATNF Pulsar Catalogue
• LOFAR: The LOw-Frequency ARray
• The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• Fermi Large Area Telescope Fourth Source Catalog
• TEMPO2, a new pulsar timing package. I: Overview
• A NICER View of the Massive Pulsar PSR J0740+6620 Informed by Radio Timing and XMM-Newton Spectroscopy
• A New Electron Density Model for Estimation of Pulsar and FRB Distances
• PSRCHIVE and PSRFITS An Open Approach to Radio Pulsar Data Storage and Analysis
• A Radio Pulsar Spinning at 716 Hz
• SWIRE: The SIRTF Wide-area InfraRed Extragalactic Survey
• Faraday Rotation Measure Synthesis
• The LOFAR Two-metre Sky Survey - I. Survey Description and Preliminary Data Release
• The Parkes Multibeam Pulsar Survey: I. Observing and Data Analysis Systems, Discovery and Timing of 100 Pulsars
• Tempo2, a new pulsar timing package. II: The timing model and precision estimates
• DSPSR: Digital Signal Processing Software for Pulsar Astronomy
• The LOFAR Two-metre Sky Survey - II. First data release
• The Parkes multibeam pulsar survey: VI. Discovery and timing of 142 pulsars and a Galactic population analysis
• The LOFAR Two-metre Sky Survey -- V. Second data release
• Fourier Techniques for Very Long Astrophysical Time Series Analysis
• The High Time Resolution Universe Pulsar Survey I: System configuration and initial discoveries
• The Last of FIRST: The Final Catalog and Source Identifications
• A millisecond pulsar in a stellar triple system
• The characteristics of millisecond pulsar emission: I. Spectra, pulse shapes and the beaming fraction
• The International Pulsar Timing Array: Second data release
• Twenty-One Millisecond Pulsars in Terzan 5 Using the Green Bank Telescope
• Pulsar Nulling and Mode Changing
• Emission Beam Geometry of Selected Pulsars Derived from Average Pulse Polarization Data
• Arecibo Pulsar Survey Using ALFA. I. Survey Strategy and First Discoveries
• The LOFAR Two Meter Sky Survey: Deep Fields, I -- Direction-dependent calibration and imaging
• Fifty Years of Pulsar Candidate Selection: From simple filters to a new principled real-time classification approach
• The Westerbork SINGS Survey II. Polarization, Faraday Rotation, and Magnetic Fields
• Spectral properties of 441 radio pulsars
• Observing pulsars and fast transients with LOFAR
• The pulsar spectral index distribution
• The Green Bank Northern Celestial Cap Pulsar Survey - I: Survey Description, Data Analysis, and Initial Results
• The FAST Galactic Plane Pulsar Snapshot survey: I. Project design and pulsar discoveries
• Formation of black widows and redbacks -- two distinct populations of eclipsing binary millisecond pulsars
• Testing the universality of free fall by tracking a pulsar in a stellar triple system
• A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope
• Calibrating High-Precision Faraday Rotation Measurements for LOFAR and the Next Generation of Low-Frequency Radio Telescopes
• Microarcsecond VLBI pulsar astrometry with PSR$\pi$ II. parallax distances for 57 pulsars
• Accelerating incoherent dedispersion
• A LOFAR census of non-recycled pulsars: average profiles, dispersion measures, flux densities, and spectra
• A radio spectral index map and catalogue at 147-1400 MHz covering 80 per cent of the sky
• Classification and Ranking of Fermi LAT Gamma-ray Sources from the 3FGL Catalog using Machine Learning Techniques
• A LOFAR census of millisecond pulsars
• LOFAR discovery of a 23.5-second radio pulsar
• Low-frequency Faraday rotation measures towards pulsars using LOFAR: probing the 3-D Galactic halo magnetic field
• Timing of young radio pulsars I: Timing noise, periodic modulation and proper motion
• A 1.4-GHz Arecibo Survey for Pulsars in Globular Clusters
• The SUrvey for Pulsars and Extragalactic Radio Bursts I: Survey Description and Overview
• The LOFAR Tied-Array All-Sky Survey (LOTAAS): Survey overview and initial pulsar discoveries
• The High Time Resolution Universe Pulsar Survey - XIII. PSR J1757-1854, the most accelerated binary pulsar
• The LOFAR Pilot Surveys for Pulsars and Fast Radio Transients
• Optimal periodicity searching: Revisiting the Fast Folding Algorithm for large-scale pulsar surveys
• Pulsar polarisation below 200 MHz: Average profiles and propagation effects
• Spin-Down of Radio Millisecond Pulsars at Genesis
• Goals, Strategies and First Discoveries of AO327, the Arecibo All-Sky 327 MHz Drift Pulsar Survey
• Eight new millisecond pulsars from the first MeerKAT globular cluster census
• The population of M dwarfs observed at low radio frequencies
• LOFAR discovery of the fastest-spinning millisecond pulsar in the Galactic field
• Linear polarization structures in LOFAR observations of the interstellar medium in the 3C196 field
• Parkes radio searches of Fermi gamma-ray sources and millisecond pulsar discoveries
• The effect of HII regions on rotation measure of pulsars
• FAST Globular Cluster Pulsar Survey: Twenty-Four Pulsars Discovered in Fifteen Globular Clusters
• Wide-Band, Low-Frequency Pulse Profiles of 100 Radio Pulsars with LOFAR
• Scattering analysis of LOFAR pulsar observations
• New constraints on the magnetization of the cosmic web using LOFAR Faraday rotation observations
• Multi-frequency integrated profiles of pulsars
• The challenges of low-frequency radio polarimetry: lessons from the Murchison Widefield Array
• Broadband Radio Polarimetry and Faraday Rotation of 563 Extragalactic Radio Sources
• Detection of new pulsars at the frequency 111 MHz
• A circular polarisation survey for radio stars with the Australian SKA Pathfinder
• Study of spider pulsar binary eclipses and discovery of an eclipse mechanism transition
• Cataloging the radio-sky with unsupervised machine learning: a new approach for the SKA era
• The GMRT High Resolution Southern Sky Survey for pulsars and transients -I. Survey description and initial discoveries
• Constraints from Faraday rotation on the magnetic field structure in the Galactic halo
• Unveiling the rarest morphologies of the LOFAR Two-metre Sky Survey radio source population with self-organised maps
• Cobalt: A GPU-based correlator and beamformer for LOFAR
• An image-based search for pulsars among Fermi unassociated LAT sources
• Gaia pulsars and where to find them
• Real-time, fast radio transient searches with GPU de-dispersion
• Direct radio discovery of a cold brown dwarf
• The Thousand-Pulsar-Array programme on MeerKAT -- V. Scattering analysis of single-component pulsars
• An in-depth investigation of 11 pulsars discovered by FAST
• First discovery of new pulsars and RRATs with CHIME/FRB
• The POlarised GLEAM Survey (POGS) II: Results from an All-Sky Rotation Measure Synthesis Survey at Long Wavelengths
• Pulsar Candidate Identification Using Semi-Supervised Generative Adversarial Networks
• Discovery of Millisecond Pulsars in the Globular Cluster Omega Centauri
• A polarization census of bright pulsars using the Ultra-Wideband Receiver on the Parkes radio telescope
• Broadband radio circular polarization spectrum of the relativistic jet in PKS B2126-158
• Faraday rotation measures of northern-hemisphere pulsars using CHIME/Pulsar
• The LOFAR Tied-Array All-Sky Survey: Timing of 21 pulsars including the first binary pulsar discovered with LOFAR
• Flux density variability of 286 radio pulsars from a decade of monitoring
• A Census of Southern Pulsars at 185 MHz
• A millisecond pulsar discovery in a survey of unidentified Fermi $\gamma$-ray sources with LOFAR
• The Tail of PSR J0002+6216 and the Supernova Remnant CTB 1
• Millisecond Pulsar Scintillation Studies with LOFAR: Initial Results
• Discovery and timing of three millisecond pulsars in radio and gamma-rays with the GMRT and Fermi-LAT
• Serendipitous Discovery of PSR J1431-6328 as a Highly-Polarized Point Source with the Australian SKA Pathfinder
• Prospects for Discovering Pulsars in Future Continuum Surveys Using Variance Imaging
• Discovery of a steep-spectrum low-luminosity pulsar with the Murchison Widefield Array
• Radio Detection of PSR J1813-1749 in HESS J1813-178: The Most Scattered Pulsar Known
• MWA Tied-Array Processing II: Polarimetric Verification and Analysis of two Bright Southern Pulsars
• A Search for Sub-millisecond Pulsations in Unidentified FIRST and NVSS Radio Sources
• LOFAR Deep Fields: Probing a broader population of polarized radio galaxies in ELAIS-N1
• A Search for Pulsars in Steep Spectrum Radio Sources
• The Galactic halo pulsar population
• A supernova remnant association for the fast-moving pulsar PSR J0908-4913
• Twenty Years of Searching for (and Finding) Globular Cluster Pulsars
• Two Extreme Steep-Spectrum, Polarized Radio Sources Towards the Galactic Bulge
• Scintillation based search for off-pulse radio emission from pulsars
• The UTMOST Survey for Magnetars, Intermittent pulsars, RRATs and FRBs I: System description and overview

Cited by in corpus (11)

• The Faraday Rotation Measure Grid of the LOFAR Two-metre Sky Survey: Data Release 2
• V-LoTSS: The Circularly-Polarised LOFAR Two-metre Sky Survey
• Pulsar polarization: a broad-band population view with the Parkes Ultra-Wideband receiver
• Radio Variable and Transient Sources on Minute Timescales in the ASKAP Pilot Surveys
• A Green Bank Telescope search for narrowband technosignatures between 1.1-1.9 GHz during 12 Kepler planetary transits
• Discovery and Timing of Millisecond Pulsars with the Arecibo 327 MHz Drift-Scan Survey
• Image-based searches for pulsar candidates using MWA VCS data
• Millisecond pulsars phenomenology under the light of graph theory
• Multiwavelength identification of millisecond pulsar candidates in the Galactic bulge
• Identification of radio and gamma-ray pulsars in X-rays using data from the SRG/eROSITA all-sky survey
• Pulsars identified in the LOFAR Two-metre Sky Survey at 144 MHz