非表示:
キーワード:
Astrophysics, High Energy Astrophysical Phenomena, astro-ph.HE, Astrophysics, Instrumentation and Methods for Astrophysics, astro-ph.IM, Astrophysics, Solar and Stellar Astrophysics, astro-ph.SR
要旨:
We report on the high-precision timing of 42 radio millisecond pulsars (MSPs)
observed by the European Pulsar Timing Array (EPTA). This EPTA Data Release 1.0
extends up to mid-2014 and baselines range from 7-18 years. It forms the basis
for the stochastic gravitational-wave background, anisotropic background, and
continuous-wave limits recently presented by the EPTA elsewhere. The Bayesian
timing analysis performed with TempoNest yields the detection of several new
parameters: seven parallaxes, nine proper motions and, in the case of six
binary pulsars, an apparent change of the semi-major axis. We find the NE2001
Galactic electron density model to be a better match to our parallax distances
(after correction from the Lutz-Kelker bias) than the M2 and M3 models by
Schnitzeler (2012). However, we measure an average uncertainty of 80\%
(fractional) for NE2001, three times larger than what is typically assumed in
the literature. We revisit the transverse velocity distribution for a set of 19
isolated and 57 binary MSPs and find no statistical difference between these
two populations. We detect Shapiro delay in the timing residuals of PSRs
J1600$-$3053 and J1918$-$0642, implying pulsar and companion masses
$m_p=1.22_{-0.35}^{+0.5} \text{M}_{\odot}$, $m_c = 0.21_{-0.04}^{+0.06}
\text{M}_{\odot }$ and $m_p=1.25_{-0.4}^{+0.6} \text{M}_{\odot}$, $m_c =
0.23_{-0.05}^{+0.07} \text{M}_{\odot }$, respectively. Finally, we use the
measurement of the orbital period derivative to set a stringent constraint on
the distance to PSRs J1012$+$5307 and J1909$-$3744, and set limits on the
longitude of ascending node through the search of the annual-orbital parallax
for PSRs J1600$-$3053 and J1909$-$3744.
