New supernova remnant candidates in the LOFAR Two Metre Sky Survey

Abstract

In spite of their key role in galaxy evolution and several decades of observational efforts, the census of supernova remnants (SNRs) in our Galaxy remains incomplete. Theoretical predictions based on the local supernova rate estimate the expected number of SNRs in the Galaxy to be $\gtrsim$ 1000. By contrast, the number of detected SNRs amounts to about 300. High-resolution, wide-area radio surveys at low frequencies are ideal tools with which to find missing SNRs, given the prominence of these sources at low radio frequencies. We aim to find missing SNRs using proprietary data from the LOFAR Two-Metre Sky Survey (LoTSS) at 144~MHz. We used LoTSS total intensity maps of two Galactic regions, one with $39^{\mathrm{o}}<l<66^{\mathrm{o}}$ and $|b|<2.5^{\mathrm{o}}$, and the other with $145^{\mathrm{o}}<l<150^{\mathrm{o}}$ and $|b|<3^{\mathrm{o}}$, in addition to mid-infrared (MIR) data from the Wide-field Infrared Survey Explorer (WISE) all-sky survey to search for SNR candidates. We report the discovery of 14 new SNR candidates selected on the basis of their morphology at 144 MHz and a lack of MIR emission. We also follow up on 24 previously reported SNR candidates, inferring their spectral index between the LoTSS frequency (144 MHz) and the frequency at which they were reported. The high resolution and sensitivity of LoTSS observations has resulted in the detection of 14 new SNR candidates. In order to unambiguously confirm the SNR nature of these candidates, follow-up X-ray observations are required with facilities such as eROSITA.

arXiv commentAccepted in A&A

References in corpus (48)

• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• LOFAR: The LOw-Frequency ARray
• How Massive Single Stars End their Life
• The VizieR database of Astronomical Catalogues
• A statistical study of 233 pulsar proper motions
• Observational clues to the progenitors of Type-Ia supernovae
• The GMRT 150 MHz All-sky Radio Survey: First Alternative Data Release TGSS ADR1
• The LOFAR Two-metre Sky Survey - I. Survey Description and Preliminary Data Release
• The LOFAR Two-metre Sky Survey - II. First data release
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue
• Nearby Supernova Rates from the Lick Observatory Supernova Search. III. The Rate-Size Relation, and the Rates as a Function of Galaxy Hubble Type and Colour
• The LOFAR Two-metre Sky Survey -- V. Second data release
• Supernova remnants: the X-ray perspective
• The VLA Galactic Plane Survey
• The WISE Catalog of Galactic HII Regions
• The SRG X-ray orbital observatory, its telescopes and first scientific results
• The Physics of Core-Collapse Supernovae
• Australian Square Kilometre Array Pathfinder: I. System Description
• Supernova Feedback in an Inhomogeneous Interstellar Medium
• The Very Large Array Low-frequency Sky Survey Redux (VLSSr)
• Global cosmic-ray related luminosity and energy budget of the Milky Way
• A revised catalogue of 294 Galactic supernova remnants
• The Green Bank Telescope HII Region Discovery Survey II. The Source Catalog
• Systematic effects in LOFAR data: A unified calibration strategy
• Discovery of 35 New Supernova Remnants in the Inner Galaxy
• Radio emission from Supernova Remnants
• LOFAR/H-ATLAS: A deep low-frequency survey of the Herschel-ATLAS North Galactic Pole field
• Arecibo Pulsar Survey Using ALFA. IV. Mock Spectrometer Data Analysis, Survey Sensitivity, and the Discovery of 41 Pulsars
• Galactic Supernova Remnant Candidates Discovered by THOR
• The Planck clusters in the LOFAR sky. I. LoTSS-DR2: new detections and sample overview
• ATLAS - I. Third Release of 1.4 GHz Mosaics and Component Catalogues
• A global view on star formation: The GLOSTAR Galactic Plane Survey. I. Overview and first results for the Galactic longitude range 28° < l < 36°
• Distances, Radial Distribution and Total Number of Galactic Supernova Remnants
• A derivation of the free-free emission on the Galactic plane between l=20 and 44 degrees
• Supernova feedback and the energy deposition in molecular clouds
• A global view on star formation: The GLOSTAR Galactic plane survey. II. Supernova Remnants in the first quadrant of the Milky Way
• Star formation triggered by SN explosions: an application to the stellar association of $\beta$ Pictoris
• Deep Radio, Optical, and Infrared Observations of SGR 1900+14
• The Radio Properties and Magnetic Field Configuration in the Crab-like Pulsar Wind Nebula G54.1+0.3
• Candidate radio supernova remnants observed by the GLEAM survey over $345^{\circ }<l<60^{\circ }$ and $180^{\circ }<l<240^{\circ }$
• A Catalogue of Radio Supernova Remnants and Candidate Supernova Remnants in the EMU/POSSUM Galactic Pilot Field
• Probing the Pulsar Wind Nebula of PSR B0355+54
• New candidate radio supernova remnants detected in the GLEAM survey over $345^{\circ }<l<60^{\circ }$, $180^{\circ }<l<240^{\circ }$
• Investigating Galactic supernova remnant candidates with LOFAR
• Study of 72 pulsars discovered in the PALFA survey: Timing analysis, glitch activity, emission variability, and a pulsar in an eccentric binary
• Diffuse radio emission from non-Planck galaxy clusters in the LoTSS-DR2 fields
• Search for and Identification of Young Compact Galactic Supernova Remnants Using THOR
• Compact Object Formation and the Supernova Explosion Engine

Cited by in corpus (1)

• NuSTAR and XMM-Newton Observations of PSR J1930+1852 and Its Pulsar Wind Nebula