Einstein@Home Searches for Gamma-ray Pulsars in the Inner Galaxy

Abstract

The Fermi Large Area Telescope (LAT) has revealed a mysterious extended excess of GeV gamma-ray emission around the Galactic Center, which can potentially be explained by unresolved emission from a population of pulsars, particularly millisecond pulsars (MSPs), in the Galactic bulge. We used the distributed volunteer computing system Einstein@Home to search the Fermi-LAT data for gamma-ray pulsations from sources in the inner Galaxy, to try to identify the brightest members of this putative population. We discovered four new pulsars, including one new MSP and one young pulsar whose angular separation to the Galactic Center of 0.93° is the smallest of any known gamma-ray pulsar. We demonstrate a phase-resolved difference imaging technique that allows the flux from this pulsar to be disentangled from the diffuse Galactic Center emission. No radio pulsations were detected from the four new pulsars in archival radio observations or during the MPIfR-MeerKAT Galactic Plane Survey. While the distances to these pulsars remain uncertain, we find that it is more likely that they are all foreground sources from the Galactic disk, rather than pulsars originating from the predicted bulge population. Nevertheless, our results are not incompatible with an MSP explanation for the GC excess, as only one or two members of this population would have been detectable in our searches.

26 pages, 5 figures. Accepted for publication in ApJ

References in corpus (100)

• Array Programming with NumPy
• Astropy: A Community Python Package for Astronomy
• The Structure of Cold Dark Matter Halos
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• The ATNF Pulsar Catalogue
• dynesty: A Dynamic Nested Sampling Package for Estimating Bayesian Posteriors and Evidences
• Fermi Large Area Telescope Fourth Source Catalog
• Bilby: A user-friendly Bayesian inference library for gravitational-wave astronomy
• A New Electron Density Model for Estimation of Pulsar and FRB Distances
• The mass distribution and gravitational potential of the Milky Way
• The Second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• Dark Matter Annihilation in The Galactic Center As Seen by the Fermi Gamma Ray Space Telescope
• Tempo2, a new pulsar timing package. II: The timing model and precision estimates
• DSPSR: Digital Signal Processing Software for Pulsar Astronomy
• Constraining Dark Matter Models from a Combined Analysis of Milky Way Satellites with the Fermi Large Area Telescope
• Open data from the first and second observing runs of Advanced LIGO and Advanced Virgo
• Switched magnetospheric regulation of pulsar spin-down
• Search templates for gravitational waves from inspiraling binaries: Choice of template spacing
• Detection of a Gamma-Ray Source in the Galactic Center Consistent with Extended Emission from Dark Matter Annihilation and Concentrated Astrophysical Emission
• Background model systematics for the Fermi GeV excess
• Fourier Techniques for Very Long Astrophysical Time Series Analysis
• The Fermi Galactic Center GeV Excess and Implications for Dark Matter
• Bayesian Blocks, A New Method to Analyze Structure in Photon Counting Data
• Detection of 16 Gamma-Ray Pulsars Through Blind Frequency Searches Using the Fermi LAT
• Open data from the third observing run of LIGO, Virgo, KAGRA and GEO
• The characteristics of millisecond pulsar emission: I. Spectra, pulse shapes and the beaming fraction
• Assessing the Role of Spin Noise in the Precision Timing of Millisecond Pulsars
• Searching for periodic sources with LIGO
• Precise Gamma-Ray Timing and Radio Observations of 17 Fermi Gamma-Ray Pulsars
• An ultra-wide bandwidth (704 to 4032 MHz) receiver for the Parkes radio telescope
• The Consistency of Fermi-LAT Observations of the Galactic Center with a Millisecond Pulsar Population in the Central Stellar Cluster
• Gravitational waves from coalescing binaries: detection strategies and Monte Carlo estimation of parameters
• Pulsar timing analysis in the presence of correlated noise
• Pass 8: Toward the Full Realization of the Fermi-LAT Scientific Potential
• The Third Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• The generalized F-statistic: multiple detectors and multiple GW pulsars
• Eight gamma-ray pulsars discovered in blind frequency searches of Fermi LAT data
• The 1.28 GHz MeerKAT Galactic Center Mosaic
• Improving Sensitivity to Weak Pulsations with Photon Probability Weighting
• The characteristics of the Galactic center excess measured with 11 years of Fermi-LAT data
• Classification and Ranking of Fermi LAT Gamma-ray Sources from the 3FGL Catalog using Machine Learning Techniques
• Discovery of Nine Gamma-Ray Pulsars in Fermi-LAT Data Using a New Blind Search Method
• Binary Millisecond Pulsar Discovery via Gamma-Ray Pulsations
• Multiwavelength Constraints on Pulsar Populations in the Galactic Center
• Searches for Gravitational Waves from Known Pulsars at Two Harmonics in 2015-2017 LIGO Data
• Timing of young radio pulsars I: Timing noise, periodic modulation and proper motion
• PSR J2021+4026 in the Gamma Cygni region: the first variable gamma-ray pulsar seen by the Fermi LAT
• A Remarkable Low-Mass X-ray Binary within 0.1 pc of the Galactic Center
• Fermi Detection of a Luminous Gamma-ray Pulsar in a Globular Cluster
• The Einstein@Home Gamma-ray Pulsar Survey. I. Search Methods, Sensitivity and Discovery of New Young Gamma-ray Pulsars
• Narrowband searches for continuous and long-duration transient gravitational waves from known pulsars in the LIGO-Virgo third observing run
• The High Time Resolution Universe Pulsar Survey VIII: The Galactic millisecond pulsar population
• Radio detection prospects for a bulge population of millisecond pulsars as suggested by Fermi LAT observations of the inner Galaxy
• Exploiting Large-Scale Correlations to Detect Continuous Gravitational Waves
• Einstein@Home discovery of four young gamma-ray pulsars in Fermi LAT data
• Discovery of a Gamma-ray Black Widow Pulsar by GPU-accelerated Einstein@Home
• Pulsar Discovery by Global Volunteer Computing
• Timing Gamma-ray Pulsars with the Fermi Large Area Telescope: Timing Noise and Astrometry
• The Einstein@Home search for radio pulsars and PSR J2007+2722 discovery
• Searching a Thousand Radio Pulsars for Gamma-ray Emission
• The Breakthrough Listen Search For Intelligent Life Near the Galactic Center I
• Pulsar searches of Fermi unassociated sources with the Effelsberg telescope
• Einstein@Home Discovery of the Gamma-ray Millisecond Pulsar PSR J2039-5617 Confirms Its Predicted Redback Nature
• Emission-rotation correlation in pulsars: new discoveries with optimal techniques
• Heartbeat of the Mouse: a young radio pulsar associated with the axisymmetric nebula G359.23-0.82
• On Detecting Millisecond Pulsars at the Galactic Center
• The MPIfR-MeerKAT Galactic Plane survey I -- System setup and early results
• Einstein@Home discovers a radio-quiet gamma-ray millisecond pulsar
• A Gamma-ray Pulsar Timing Array Constrains the Nanohertz Gravitational Wave Background
• Deep Einstein@Home all-sky search for continuous gravitational waves in LIGO O3 public data
• Wide field beamformed observation with MeerKAT
• The TRAPUM L-band survey for pulsars in Fermi-LAT gamma-ray sources
• Population syntheses of millisecond pulsars from the Galactic Disk and Bulge
• Detection and timing of gamma-ray pulsations from the $707$ Hz pulsar J0952$-$0607
• Extending the Event-weighted Pulsation Search to Very Faint Gamma-ray Sources
• Contribution to diffuse gamma-rays in the Galactic center region from unresolved millisecond pulsars
• Comparing the Galactic Bulge and Galactic Disk Millisecond Pulsars
• Optimal Template Banks
• The Einstein@Home Gamma-Ray Pulsar Survey II. Source Selection, Spectral Analysis and Multi-wavelength Follow-up
• Event Weighted Tests for Detecting Periodicity in Photon Arrival Times
• Exploiting Orbital Constraints from Optical Data to Detect Binary Gamma-ray Pulsars
• New searches for continuous gravitational waves from seven fast pulsars
• PSR J1906+0722: An Elusive Gamma-ray Pulsar
• Optimized Blind Gamma-ray Pulsar Searches at Fixed Computing Budget
• Search for pulsed gamma-ray emission from globular cluster M28
• PulsarX: a new pulsar searching package -I. A high performance folding program for pulsar surveys
• Discovery and timing of three millisecond pulsars in radio and gamma-rays with the GMRT and Fermi-LAT
• The Galactic bulge millisecond pulsars shining in X rays: A gamma-ray perspective
• Sliding coherence window technique for hierarchical detection of continuous gravitational waves
• Discovery of gamma-ray pulsations of PSR J1835$-$3259B in the Globular Cluster NGC 6652
• Likely detection of gamma-ray pulsations of PSR~J1717+4308A in NGC~6341 and implication of the gamma-ray millisecond pulsars in globular clusters
• A New Determination of the Millisecond Pulsar Gamma-Ray Luminosity Function and Implications for the Galactic Center Gamma-Ray Excess
• Bayesian $\mathcal{F}$-statistic-based parameter estimation of continuous gravitational waves from known pulsars
• Towards resolving the Galactic center GeV excess with millisecond-pulsar-like sources using machine learning
• A 350-MHz Green Bank Telescope Survey of Unassociated Fermi LAT Sources: Discovery and Timing of Ten Millisecond Pulsars
• An Investigation of the state changes of PSR J2021+4026 and the Vela pulsar
• VLA proper motion constraints on the origin, age, and potential magnetar future of PSR J1734$-$3333
• Multiwavelength identification of millisecond pulsar candidates in the Galactic bulge

Cited by in corpus (2)

• Timing Gamma-ray Pulsars using Gibbs Sampling
• Exploring the nature of Galactic unassociated sources detected by the Fermi-LAT