English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We demonstrate how pulsar timing arrays (PTAs) can, in principle, yield apurely gravitational wave (GW) measurement of the luminosity distance andcomoving distance to a supermassive black hole binary source, hence providingan estimate of the source redshift and the Hubble constant. The luminositydistance is derived through standard measurement of the chirp mass, which forthe slowly evolving binary sources in the PTA band can be found by comparingthe frequency of GW-timing residuals at the Earth compared to those at distantpulsars in the array. The comoving distance can be measured from GW-timingparallax caused by the curvature of the GW wavefronts. This can be detected forsingle sources at the high-frequency end of the PTA band out to Gpc distanceswith a future PTA containing well-timed pulsars out to $\mathcal{O}(10)$ kpc,when the pulsar distance is constrained to less than a GW wavelength. Such afuture PTA, with $\gtrsim 30$ pulsars with precise distance measurementsbetween 1 and 20~kpc, could measure the Hubble constant at the tens of percentlevel for a single source at $0.1 \lesssim z \lesssim 1.5$. At $z \lesssim0.1$, the luminosity and comoving distances are too similar to disentangle,unless the fractional error in the luminosity distance measurement is decreasedbelow 10%. At $z\gtrsim 1.5$, this measurement will likely be restricted by asignal-to-noise ratio threshold. Generally, clarification of the differenttypes of cosmological distances that can be probed by PTAs, and their relationto pulsar distance measurements is important for ongoing PTA experiments aimedat detecting and characterizing GWs.

Using Gravitational Wave Parallax to Measure the Hubble Parameter with Pulsar Timing Arrays