Pulsar Observations at Low Frequencies: Applications to Pulsar Timing and Solar Wind Models

Abstract

Efforts are underway to use high-precision timing of pulsars in order to detect low-frequency gravitational waves. A limit to this technique is the timing noise generated by dispersion in the plasma along the line of sight to the pulsar, including the solar wind. The effects due to the solar wind vary with time, influenced by the change in solar activity on different time scales, ranging up to $\sim 11$ years for a solar cycle. The solar wind contribution depends strongly on the angle between the pulsar line of sight and the solar disk, and is a dominant effect at small separations. Although solar wind models to mitigate these effects do exist, they do not account for all the effects of the solar wind and its temporal changes. Since low-frequency pulsar observations are most sensitive to these dispersive delays, they are most suited to test the efficacy of these models and identify alternative approaches. Here, we investigate the efficacy of some solar wind models commonly used in pulsar timing using long-term, high-cadence data on 6 pulsars taken with the Long Wavelength Array, and compare them with an operational solar wind model. Our results show that stationary models of the solar wind correction are insufficient to achieve the timing noise desired by pulsar timing experiments, and we need to use non-stationary models, which are informed by other solar wind observations, to obtain accurate timing residuals.

arXiv commentAccepted for publication in MNRAS. 15 pages, 7 figures

References in corpus (33)

• The ATNF Pulsar Catalogue
• TEMPO2, a new pulsar timing package. I: Overview
• Tempo2, a new pulsar timing package. II: The timing model and precision estimates
• Binary and Millisecond Pulsars
• High-precision timing of 42 millisecond pulsars with the European Pulsar Timing Array
• Limits on the Stochastic Gravitational Wave Background from the North American Nanohertz Observatory for Gravitational Waves
• Common-red-signal analysis with 24-yr high-precision timing of the European Pulsar Timing Array: Inferences in the stochastic gravitational-wave background search
• Measurement and correction of variations in interstellar dispersion in high-precision pulsar timing
• Advancements in the ADAPT Photospheric Flux Transport Model
• The LWA1 Radio Telescope
• The Parkes Pulsar Timing Array Project: Second data release
• The NANOGrav Nine-Year Data Set: Measurement and Interpretation of Variations in Dispersion Measures
• Frequency-Dependent Dispersion Measures and Implications for Pulsar Timing
• The NANOGrav 12.5-year Data Set: Wideband Timing of 47 Millisecond Pulsars
• First search for nontensorial gravitational waves from known pulsars
• Pulsar Observations Using the First Station of the Long Wavelength Array and the LWA Pulsar Data Archive
• Profile shape stability and phase jitter analyses of millisecond pulsars
• An improved solar wind electron-density model for pulsar timing
• The impact of Solar wind variability on pulsar timing
• Measurement of the electron density and magnetic field of the solar wind using millisecond pulsars
• Dispersion measure variability for 36 millisecond pulsars at 150MHz with LOFAR
• On the usefulness of existing Solar-wind models for pulsar timing corrections
• The Long Wavelength Array Software Library
• The NANOGrav 11-year Data Set: Solar Wind Sounding Through Pulsar Timing
• Multi-frequency scatter broadening evolution of pulsars - I
• Scattering study of Pulsars below 100 MHz using LWA1
• High Precision Measurements of Interstellar Dispersion Measure with the upgraded GMRT
• The effect of Pulse profile evolution on Pulsar Dispersion Measure
• Pulsar timing and its applications
• Modeling the Ionosphere with GPS and Rotation Measure Observations
• On Frequency-Dependent Dispersion Measures and Extreme Scattering Events
• Detection of Echoes in PSR B1508+55 at frequencies below 100 MHz using the LWA1
• CMEchaser, detecting line-of-sight occultations due to Coronal Mass Ejections

Cited by in corpus (8)

• The gravitational-wave background null hypothesis: Characterizing noise in millisecond pulsar arrival times with the Parkes Pulsar Timing Array
• Bayesian Solar Wind Modeling with Pulsar Timing Arrays
• Exploring the time variability of the Solar Wind using LOFAR pulsar data
• Validation of heliospheric modeling algorithms through pulsar observations I: Interplanetary scintillation-based tomography
• Multi-messenger observations of double neutron stars in Galactic disk with gravitational and radio waves
• A Multifrequency Census of 100 Pulsars below 100 MHz with LWA: A Systematic Study of Flux Density, Spectra, Timing, Dispersion, Polarization, and Its Variation from a Decade of Observations
• Design and Commissioning of an LWA Swarm Station: The Long Wavelength Array -- North Arm
• 50-250 MHz Pulsar Census with an SKA-Low prototype station: Spectra and Polarization