CHIME Discovery of a Binary Pulsar with a Massive Non-Degenerate Companion

Abstract

Of the more than $3,000$ radio pulsars currently known, only $\sim 300$ are in binary systems, and only five of these consist of young pulsars with massive non-degenerate companions. We present the discovery and initial timing, accomplished using the Canadian Hydrogen Intensity Mapping Experiment telescope (CHIME), of the sixth such binary pulsar, PSR J2108+4516, a $0.577$-s radio pulsar in a 269-day orbit of eccentricity 0.09 with a companion of minimum mass $11$ M${}_{\odot }$. Notably, the pulsar undergoes periods of substantial eclipse, disappearing from the CHIME $400-800$ MHz observing band for a large fraction of its orbit, and displays significant dispersion measure and scattering variations throughout its orbit, pointing to the possibility of a circumstellar disk or very dense stellar wind associated with the companion star. Subarcsecond resolution imaging with the Karl G. Jansky Very Large Array unambiguously demonstrates that the companion is a bright, $V\simeq 11$ OBe star, EM* UHA 138, located at a distance of $3.26(14)$ kpc. Archival optical observations of \companion{} approximately suggest a companion mass ranging from $17.5$ M${}_{\odot }<M_{\mathrm{c}}<23$ M${}_{\odot }$, in turn constraining the orbital inclination angle to $50.3^{\circ }\lesssim i\lesssim 58.3^{\circ }$. With further multi-wavelength followup, PSR J2108+4516 promises to serve as another rare laboratory for the exploration of companion winds, circumstellar disks, and short-term evolution through extended-body orbital dynamics.

arXiv comment20 pages, 12 figures, accepted by ApJ

References in corpus (57)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• The Gaia mission
• Intrinsic Colors, Temperatures, and Bolometric Corrections of Pre-Main Sequence Stars
• The SIMBAD astronomical database
• The VizieR database of Astronomical Catalogues
• A statistical study of 233 pulsar proper motions
• A 3D Dust Map Based on Gaia, Pan-STARRS 1 and 2MASS
• The All-Sky Automated Survey for Supernovae (ASAS-SN) Light Curve Server v1.0
• 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
• Observations of Accreting Pulsars
• DSPSR: Digital Signal Processing Software for Pulsar Astronomy
• The Parkes multibeam pulsar survey: VI. Discovery and timing of 142 pulsars and a Galactic population analysis
• The First CHIME/FRB Fast Radio Burst Catalog
• Dense magnetized plasma associated with a fast radio burst
• The CHIME Fast Radio Burst Project: System Overview
• Limits on the Stochastic Gravitational Wave Background from the North American Nanohertz Observatory for Gravitational Waves
• Multifrequency Observations of Radio Pulse Broadening and Constraints on Interstellar Electron Density Microstructure
• Discovery of the Binary Pulsar PSR B1259-63 in Very-High-Energy Gamma Rays around Periastron with H.E.S.S
• Be-star rotation: how close to critical?
• The NANOGrav Nine-year Data Set: Limits on the Isotropic Stochastic Gravitational Wave Background
• An analysis of the timing irregularities for 366 pulsars
• Pulsar Nulling and Mode Changing
• Assessing the Role of Spin Noise in the Precision Timing of Millisecond Pulsars
• Measurement and correction of variations in interstellar dispersion in high-precision pulsar timing
• A New Class of High-Mass X-ray Binaries: Implications for Core Collapse and Neutron-Star Recoil
• Discovery of High-Energy Gamma-Ray Emission from the Binary System PSR B1259-63/LS 2883 Around Periastron with Fermi
• The NANOGrav 12.5 yr Data Set: Observations and Narrowband Timing of 47 Millisecond Pulsars
• Dispersion Measure Variations and their Effect on Precision Pulsar Timing
• Two Populations of X-ray Pulsars Produced by Two Types of Supernovae
• The NANOGrav Nine-Year Data Set: Measurement and Interpretation of Variations in Dispersion Measures
• Elementary Wideband Timing of Radio Pulsars
• The High Time Resolution Universe survey XIV: Discovery of 23 pulsars through GPU-accelerated reprocessing
• The CHIME Pulsar Project: System Overview
• Measuring pulse times of arrival from broadband pulsar observations
• The kinematics and orbital dynamics of the PSR B1259$-$63/LS 2883 system from 23 years of pulsar timing
• Multiwavelength monitoring and X-ray brightening of Be X-ray binary PSR J2032+4127/MT91 213 on its approach to periastron
• INTEGRAL and XMM-Newton observations of LSI +61 303
• Revealing the structure of the outer disks of Be stars
• Frequency-Dependent Template Profiles for High Precision Pulsar Timing
• SPIN-ORBIT INTERACTION IN NEUTRON STAR/MAIN SEQUENCE BINARIES AND IMPLICATIONS FOR PULSAR TIMING
• Dispersion measure variations in a sample of 168 pulsars
• The Low-Frequency Radio Eclipses of the Black Widow Pulsar J1810+1744
• PSR J1740-3052 - a pulsar with a massive companion
• Temporal variations in scattering and dispersion measure in the Crab Pulsar and their effect on timing precision
• The Analytical Solution to the Temporal Broadening of a Gaussian-Shaped Radio Pulse by Multipath Scattering from a Thin Screen in the Interstellar Medium
• First discovery of new pulsars and RRATs with CHIME/FRB
• Timing the main-sequence-star binary pulsar J1740-3052
• Unusually bright single pulses from B1744-24A binary: a case of strong lensing?
• PONDER - A Real time software backend for pulsar and IPS observations at the Ooty Radio Telescope
• Discovery and modelling of broad-scale plasma lensing in black-widow pulsar J2051$-$0827
• Study of 72 pulsars discovered in the PALFA survey: Timing analysis, glitch activity, emission variability, and a pulsar in an eccentric binary
• Timing of PSR J2055+3829, an eclipsing black widow pulsar discovered with the Nançay Radio Telescope
• Low-frequency wideband timing of InPTA pulsars observed with the uGMRT
• Multi-wavelength observations of PSRJ 2032+4127 during the 2017 periastron passage
• The binary companion of PSR J1740-3052
• A Study in Frequency-Dependent Effects on Precision Pulsar Timing Parameters with the Pulsar Signal Simulator