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Title: ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS

Abstract

We investigate rotational spin noise (referred to as timing noise) in non-accreting pulsars: millisecond pulsars, canonical pulsars, and magnetars. Particular attention is placed on quantifying the strength and non-stationarity of timing noise in millisecond pulsars because the long-term stability of these objects is required to detect nanohertz gravitational radiation. We show that a single scaling law is sufficient to characterize timing noise in millisecond and canonical pulsars while the same scaling law underestimates the levels of timing noise in magnetars. The scaling law, along with a detailed study of the millisecond pulsar B1937+21, leads us to conclude that timing noise is latent in most millisecond pulsars and will be measurable in many objects when better arrival time estimates are obtained over long data spans. The sensitivity of a pulsar timing array to gravitational radiation is strongly affected by any timing noise. We conclude that detection of proposed gravitational wave backgrounds will require the analysis of more objects than previously suggested over data spans that depend on the spectra of both the gravitational wave background and of the timing noise. It is imperative to find additional millisecond pulsars in current and future surveys in order to reduce the effects of timingmore » noise.« less

Authors:
;  [1]
  1. Astronomy Department, Cornell University, Ithaca, NY 14853 (United States)
Publication Date:
OSTI Identifier:
21476698
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 725; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/725/2/1607
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMIC NEUTRONS; GRAVITATIONAL RADIATION; GRAVITATIONAL WAVES; NEUTRON STARS; PULSARS; SCALING LAWS; BARYONS; COSMIC RADIATION; COSMIC RADIO SOURCES; ELEMENTARY PARTICLES; FERMIONS; HADRONS; IONIZING RADIATIONS; NEUTRONS; NUCLEONS; RADIATIONS; SECONDARY COSMIC RADIATION; STARS

Citation Formats

Shannon, Ryan M., and Cordes, James M., E-mail: ryans@astro.cornell.ed, E-mail: cordes@astro.cornell.ed. ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS. United States: N. p., 2010. Web. doi:10.1088/0004-637X/725/2/1607.
Shannon, Ryan M., & Cordes, James M., E-mail: ryans@astro.cornell.ed, E-mail: cordes@astro.cornell.ed. ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS. United States. doi:10.1088/0004-637X/725/2/1607.
Shannon, Ryan M., and Cordes, James M., E-mail: ryans@astro.cornell.ed, E-mail: cordes@astro.cornell.ed. 2010. "ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS". United States. doi:10.1088/0004-637X/725/2/1607.
@article{osti_21476698,
title = {ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS},
author = {Shannon, Ryan M. and Cordes, James M., E-mail: ryans@astro.cornell.ed, E-mail: cordes@astro.cornell.ed},
abstractNote = {We investigate rotational spin noise (referred to as timing noise) in non-accreting pulsars: millisecond pulsars, canonical pulsars, and magnetars. Particular attention is placed on quantifying the strength and non-stationarity of timing noise in millisecond pulsars because the long-term stability of these objects is required to detect nanohertz gravitational radiation. We show that a single scaling law is sufficient to characterize timing noise in millisecond and canonical pulsars while the same scaling law underestimates the levels of timing noise in magnetars. The scaling law, along with a detailed study of the millisecond pulsar B1937+21, leads us to conclude that timing noise is latent in most millisecond pulsars and will be measurable in many objects when better arrival time estimates are obtained over long data spans. The sensitivity of a pulsar timing array to gravitational radiation is strongly affected by any timing noise. We conclude that detection of proposed gravitational wave backgrounds will require the analysis of more objects than previously suggested over data spans that depend on the spectra of both the gravitational wave background and of the timing noise. It is imperative to find additional millisecond pulsars in current and future surveys in order to reduce the effects of timing noise.},
doi = {10.1088/0004-637X/725/2/1607},
journal = {Astrophysical Journal},
number = 2,
volume = 725,
place = {United States},
year = 2010,
month =
}
  • The observing method, data-analysis procedures, and results of a 4.4-year series of timing observations of a binary millisecond pulsar PSR 1855 + 09 are presented. The spin parameters of the pulsar, astrometry of the system, including parallax and proper motion, and orbital parameters including masses of the two components are considered. The parameter values show the orbital inclination to be nearly 90 deg, and they provide mass estimates for the pulsar (1.27 + 0.23/{minus}0.15 solar mass) and companion star (0.233 + 0.026/{minus}0.017 solar mass). Both masses are found in good agreement with theoretical predictions based on neutron-star physics and evolutionarymore » models of the PSR 1855 + 09 system. 35 refs.« less
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