Eight new millisecond pulsars from the first MeerKAT globular cluster census

Abstract

We have used the central 44 antennas of the new 64-dish MeerKAT radio telescope array to conduct a deep search for new pulsars in the core of nine globular clusters. This has led to the discovery of eight new millisecond pulsars in six different clusters. Two new binaries, 47 Tuc ac and 47 Tuc ad, are eclipsing "spiders", featuring compact orbits ($\lesssim 0.32$ days), very low-mass companions and regular occultations of their pulsed emission. The other three new binary pulsars (NGC 6624G, M62G, and Ter 5 an) are in wider ($>0.7$ days) orbits, with companions that are likely to be white dwarfs or neutron stars. NGC 6624G has a large eccentricity of $e\simeq 0.38$, which enabled us to detect the rate of advance of periastron. This suggests that the system is massive, with a total mass of $M\mathrm{tot}=2.65\pm 0.07$ M${}_{\odot }$. Likewise, for Ter 5 an, with $e\simeq 0.0066$, we obtain $M\mathrm{tot}=2.97\pm 0.52$ M${}_{\odot }$. The other three new discoveries (NGC 6522D, NGC 6624H and NGC 6752F) are faint isolated pulsars. Finally, we have used the whole MeerKAT array and synthesized 288 beams, covering an area of $\sim 2$ arcmin in radius around the center of NGC 6624. This has allowed us to localize many of the pulsars in the cluster, demonstrating the beamforming capabilities of the TRAPUM software backend and paving the way for the upcoming MeerKAT globular cluster pulsar survey.

20 pages, 10 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Society

References in corpus (16)

• PSRCHIVE and PSRFITS An Open Approach to Radio Pulsar Data Storage and Analysis
• The Five-Hundred-Meter Aperture Spherical Radio Telescope (FAST) Project
• The MeerKAT Telescope as a Pulsar Facility: System verification and early science results from MeerTime
• A 1.4-GHz Arecibo Survey for Pulsars in Globular Clusters
• A New Catalog of Globular Clusters in the Milky Way
• Evidence for an intermediate-mass black hole in the globular cluster NGC 6624
• Pulsar-black hole binaries: prospects for new gravity tests with future radio telescopes
• Long-term observations of the pulsars in 47 Tucanae. I. A study of four elusive binary systems
• GBT Discovery of Two Binary Millisecond Pulsars in the Globular Cluster M30
• A Highly Eccentric 3.9-Millisecond Binary Pulsar in the Globular Cluster NGC 6652
• Discovery of Millisecond Pulsars in the Globular Cluster Omega Centauri
• Evidence of non-luminous matter in the center of M62
• Timing of millisecond pulsars in NGC 6752 - II. Proper motions of the pulsars in the cluster outskirts
• Giant pulses from J1823-3021A observed with the MeerKAT telescope
• Twenty Years of Searching for (and Finding) Globular Cluster Pulsars
• Wideband Monitoring Observations of PSR J1803-3002A in the Globular Cluster NGC 6522

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