Constraints on the Emission Geometries and Spin Evolution of Gamma-ray Millisecond Pulsars

Abstract

Millisecond pulsars (MSPs) are a growing class of gamma-ray emitters. Pulsed gamma-ray signals have been detected from more than 40 MSPs with the Fermi Large Area Telescope (LAT). The wider radio beams and more compact magnetospheres of MSPs enable studies of emission geometries over a broader range of phase space than non-recycled radio-loud gamma-ray pulsars. We have modeled the gamma-ray light curves of 40 LAT-detected MSPs using geometric emission models assuming a vacuum retarded-dipole magnetic field. We modeled the radio profiles using a single-altitude hollow-cone beam, with a core component when indicated by polarimetry; however, for MSPs with gamma-ray and radio light curve peaks occurring at nearly the same rotational phase we assume that the radio emission is co-located with the gamma rays and caustic in nature. The best-fit parameters and confidence intervals are determined using a maximum likelihood technique. We divide the light curves into three model classes, with gamma-ray peaks trailing (Class I), aligned (Class II) or leading (Class III) the radio peaks. Outer gap and slot gap (two-pole caustic) models best fit roughly equal numbers of Class I and II, while Class III are exclusively fit with pair-starved polar cap models. Distinguishing between the model classes based on typical derived parameters is difficult. We explore the evolution of magnetic inclination angle with period and spin-down power, finding possible correlations. While the presence of significant off-peak emission can often be used as a discriminator between outer gap and slot gap models, a hybrid model may be needed.

Accepted for publication in ApJS, auxiliary files can be found at the entry for this paper at http://www-glast.stanford.edu/cgi-bin/pubpub

References in corpus (22)

• Shapiro delay measurement of a two solar mass neutron star
• A Massive Pulsar in a Compact Relativistic Binary
• The ATNF Pulsar Catalogue
• A Radio Pulsar/X-ray Binary Link
• Three Millisecond Pulsars in FERMI LAT Unassociated Bright Sources
• High-Altitude Emission from Pulsar Slot Gaps: The Crab Pulsar
• Fitting Pulsar Wind Tori. II. Error Analysis and Applications
• Constraints on Neutron Star Properties from X-ray Observations of Millisecond Pulsars
• Population synthesis of radio and gamma-ray millisecond pulsars from the Galactic disk
• Pulsar Timing for the Fermi Gamma-ray Space Telescope
• Radio Searches of Fermi LAT Sources and Blind Search Pulsars: The Fermi Pulsar Search Consortium
• A Survey of 56 Mid-latitude EGRET Error Boxes for Radio Pulsars
• Thermal X-rays from Millisecond Pulsars: Constraining the Fundamental Properties of Neutron Stars
• The light curve of the companion to PSR B1957+20
• Radio-to-TeV Phase-resolved Emission from the Crab Pulsar: The Annular Gap Model
• Six millisecond pulsars detected by the Fermi Large Area Telescope and the radio/gamma-ray connection of millisecond pulsars
• Discovery of Five Recycled Pulsars in a High Galactic Latitude Survey
• Pulsed Gamma-rays from the millisecond pulsar J0030+0451 with the Fermi Large Area Telescope
• On the role of the current loss in radio pulsar evolution
• The annular gap model for gamma-ray emission from young and millisecond pulsars
• Gamma-ray Emission from the Vela Pulsar Modeled with the Annular Gap and Core Gap
• Constraints on the Emission Geometries of Gamma-ray Millisecond Pulsars Observed with the Fermi Large Area Telescope

Cited by in corpus (40)

• PSR J0030+0451 Mass and Radius from NICER Data and Implications for the Properties of Neutron Star Matter
• A NICER View of PSR J0030+0451: Millisecond Pulsar Parameter Estimation
• A NICER view of PSR J0030+0451: evidence for a global-scale multipolar magnetic field
• Pulsar Radio Emission Mechanism: Radio Nanoshots as a Low Frequency Afterglow of Relativistic Magnetic Reconnection
• LOFAR discovery of the fastest-spinning millisecond pulsar in the Galactic field
• The Crab Pulsar at Centimeter Wavelengths II: Single Pulses
• Evidence for an intermediate-mass black hole in the globular cluster NGC 6624
• The Einstein@Home Gamma-ray Pulsar Survey. I. Search Methods, Sensitivity and Discovery of New Young Gamma-ray Pulsars
• Diffuse gamma-ray emission from galactic pulsars
• The MPIfR-MeerKAT Galactic Plane survey I -- System setup and early results
• Discovery of Gamma-ray Pulsations from the Transitional Redback PSR J1227-4853
• Cosmic-ray positrons from millisecond pulsars
• Radio-quiet and radio-loud pulsars: similar in Gamma-rays but different in X-rays
• Neutron star mass estimates from gamma-ray eclipses in spider millisecond pulsar binaries
• A broadband radio study of the average profile and giant pulses from PSR B1821-24A
• The Braking Index of a Radio-quiet Gamma-ray Pulsar
• Three-dimensional non-vacuum pulsar outer-gap model: Localized acceleration electric field in the higher altitudes
• An assessment of the pulsar outer gap model. I: Assumptions, uncertainties, and implications for the gap size and the accelerating field
• Six Faint Gamma-ray Pulsars Seen with the Fermi Large Area Telescope -- Towards a Sample Blending into the Background
• The Green Bank North Celestial Cap Survey. VII. 12 New Pulsar Timing Solutions
• Pulsar gamma-ray emission in the radiation reaction regime
• Discovery of Soft X-ray Pulsations from PSR J1231-1411 using NICER
• A millisecond pulsar discovery in a survey of unidentified Fermi $\gamma$-ray sources with LOFAR
• Discovery and timing of three millisecond pulsars in radio and gamma-rays with the GMRT and Fermi-LAT
• Discovery, Timing, and Multiwavelength Observations of the Black Widow Millisecond Pulsar PSR J1555-2908
• Probing the High-energy $\gamma$-ray Emission Mechanism in the Vela Pulsar via Phase-resolved Spectral and Energy-dependent Light Curve Modeling
• NuSTAR and Parkes observations of the transitional millisecond pulsar binary XSS J12270-4859 in the rotation-powered state
• The effect of an offset polar cap dipolar magnetic field on the modeling of the Vela pulsar's $\gamma$-ray light curves
• The peculiar chemical abundance of the transitional millisecond pulsar PSR J1023+0038 -- Li enhancement
• Constraining the magnetic field geometry of the millisecond pulsar PSR~J0030+0451 from joint radio, thermal X-ray and $\gamma$-ray emission
• Synthetic pulsar lightcurves from global kinetic simulations and comparison with the Fermi-LAT catalog
• Magnetic Inclination Evolution of Accreting Neutron Stars in Intermediate/Low-Mass X-ray Binaries
• Follow-up of 27 radio-quiet gamma-ray pulsars at 110-190 MHz using the international LOFAR station FR606
• A short review of the pulsar magnetic inclination angles (II)
• Constraining the geometry of PSR J0855-4644: A nearby Pulsar Wind Nebula with Double Torus/Jet Morphology
• A 350-MHz Green Bank Telescope Survey of Unassociated Fermi LAT Sources: Discovery and Timing of Ten Millisecond Pulsars
• Thermal X-ray emission identified from the millisecond pulsar PSR J1909-3744
• Radio and gamma-ray timing of TRAPUM L-band Fermi pulsar survey discoveries
• Gamma-Ray Millisecond Pulsars: Off-pulse Emission Characteristics, Phase-Resolved Pseudo-Luminosity--Cutoff Energy Correlation, and High-energy Pulsed Emission
• The Effect of Pulsar Geometry on the Observed Gamma-ray Spectrum of Millisecond Pulsars