The international pulsar timing array: First data release
Downloadable Content
Abstract
- The highly stable spin of neutron stars can be exploited for a variety of (astro)physical investigations.
In particular, arrays of pulsars with rotational periods of the order of milliseconds can
be used to detect correlated signals such as those caused by gravitational waves. Three such
‘pulsar timing arrays’ (PTAs) have been set up around the world over the past decades and collectively
form the ‘International’ PTA (IPTA). In this paper, we describe the first joint analysis
of the data from the three regional PTAs, i.e. of the first IPTA data set. We describe the available
PTA data, the approach presently followed for its combination and suggest improvements
for future PTA research. Particular attention is paid to subtle details (such as underestimation
of measurement uncertainty and long-period noise) that have often been ignored but which
become important in this unprecedentedly large and inhomogeneous data set.We identify and
describe in detail several factors that complicate IPTA research and provide recommendations
for future pulsar timing efforts. The first IPTA data release presented here (and available online)
is used to demonstrate the IPTA’s potential of improving upon gravitational-wave limits placed by individual PTAs by a factor of ∼2 and provides a 2σ limit on the dimensionless
amplitude of a stochastic gravitational-wave background of 1.7 × 10−15 at a frequency of
1 yr−1. This is 1.7 times less constraining than the limit placed by Shannon et al., due mostly
to the more recent, high-quality data they used.
Contains
File | Nice-MonthlyNoticesoftheRoyalAstronomicalSociety-vol458-2016.pdf | Uploaded 2019-10-20 | Public | Download |