A millisecond pulsar position determined to 0.2 milliarcsecond precision with VLBI

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ding, Hao, Deller, Adam T., Freire, Paulo C. C., Petrov, Leonid
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910676228767744
author Ding, Hao
Deller, Adam T.
Freire, Paulo C. C.
Petrov, Leonid
author_facet Ding, Hao
Deller, Adam T.
Freire, Paulo C. C.
Petrov, Leonid
contents Precise millisecond pulsar (MSP) positions determined with very long baseline interferometry (VLBI) hold the key to building the connection between the kinematic and dynamic reference frames respectively used by VLBI and pulsar timing. The frame connection would provide an important pathway to examining the planetary ephemerides used in pulsar timing, and potentially enhancing the sensitivities of pulsar timing arrays used to detect stochastic gravitational-wave background at nano-Hz regime. We aim at significantly improving the VLBI-based MSP position from its current $\gtrsim1\,$mas precision level by reducing the two dominant components in the positional uncertainty -- the propagation-related uncertainty and the uncertainty resulting from the frequency-dependent core shifts of the reference sources. We introduce a new differential astrometry strategy of using multiple calibrators observed at several widely separated frequencies, which we call PINPT (Phase-screen Interpolation plus frequeNcy-dePendent core shifT correction; read as "pinpoint") for brevity. The strategy allows determination of the core-shift and mitigates the impact of residual delay in the atmosphere. We implemented the strategy on PSR J2222-0137, an MSP well constrained astrometrically with VLBI and pulsar timing. Using the PINPT strategy, we determined core shifts for 4 AGNs around PSR J2222-0137, and derived a VLBI-based pulsar position with uncertainty of 0.17 mas and 0.32 mas in right ascension and declination, respectively, approaching the uncertainty level of the best-determined timing-based MSP positions. The realization of the PINPT strategy promises a factor-of-5 positional precision enhancement (over conventional VLBI astrometry) for all kinds of compact radio sources observed at $\lesssim2$ GHz, including most fast radio bursts.
format Preprint
id arxiv_https___arxiv_org_abs_2407_13324
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A millisecond pulsar position determined to 0.2 milliarcsecond precision with VLBI
Ding, Hao
Deller, Adam T.
Freire, Paulo C. C.
Petrov, Leonid
Instrumentation and Methods for Astrophysics
High Energy Astrophysical Phenomena
Precise millisecond pulsar (MSP) positions determined with very long baseline interferometry (VLBI) hold the key to building the connection between the kinematic and dynamic reference frames respectively used by VLBI and pulsar timing. The frame connection would provide an important pathway to examining the planetary ephemerides used in pulsar timing, and potentially enhancing the sensitivities of pulsar timing arrays used to detect stochastic gravitational-wave background at nano-Hz regime. We aim at significantly improving the VLBI-based MSP position from its current $\gtrsim1\,$mas precision level by reducing the two dominant components in the positional uncertainty -- the propagation-related uncertainty and the uncertainty resulting from the frequency-dependent core shifts of the reference sources. We introduce a new differential astrometry strategy of using multiple calibrators observed at several widely separated frequencies, which we call PINPT (Phase-screen Interpolation plus frequeNcy-dePendent core shifT correction; read as "pinpoint") for brevity. The strategy allows determination of the core-shift and mitigates the impact of residual delay in the atmosphere. We implemented the strategy on PSR J2222-0137, an MSP well constrained astrometrically with VLBI and pulsar timing. Using the PINPT strategy, we determined core shifts for 4 AGNs around PSR J2222-0137, and derived a VLBI-based pulsar position with uncertainty of 0.17 mas and 0.32 mas in right ascension and declination, respectively, approaching the uncertainty level of the best-determined timing-based MSP positions. The realization of the PINPT strategy promises a factor-of-5 positional precision enhancement (over conventional VLBI astrometry) for all kinds of compact radio sources observed at $\lesssim2$ GHz, including most fast radio bursts.
title A millisecond pulsar position determined to 0.2 milliarcsecond precision with VLBI
topic Instrumentation and Methods for Astrophysics
High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2407.13324