NANOGrav recently made headlines by observing the stochastic gravitational waves background produced by the combination of many supermassive black hole binaries. Will a Pulsar Timing Array successfully pinpoint and resolve a specific supermassive black hole binary as a point source of gravitational waves before the year 2030.
This question will be resolved with a "YES" if a Pulsar Timing Arrays colaboration announces the successful identification of a point source of gravitational waves with a significance exceeding 3σ by the year 2030. Otherwise, it will be resolved as "NO."
1,000
3.00The PTA Wikipedia page has an interesting, but unsourced claim.
It is not possible to get accurate sky locations for the sources by this method, as analysing timings for twenty pulsars would produce a region of uncertainty of 100 square degrees – a patch of sky about the size of the constellation Scutum which would contain at least thousands of merging galaxies.
A recent theory piece on the Arxiv counters:
We found that even in a currently practical case with 100 ns white noise, if half of the pulsars have a distance precision of 1 pc, the localization can improve by more than 1 order of magnitude compared with a case without external distance information. Furthermore, in a case with 10 ns white noise and 1 pc distance precision for all pulsars, which will be practical in the SKA era, the localization can improve by 2 orders of magnitude and the uncertainty area reaches 10 amin2 . If even only a few pulsars have a distance precision of 0.1 pc, the improvement is much more drastic.
10 amin^2 would be sufficient precision to localize to a region of a low single digit number of merging galaxies, and with luck just one, which would be sufficient to find the binary pair. The SKA (Square Kilometer Array) is not expected to be completed until 2028 however, and would presumably have a testing phase before full operation. Once in operation, it would need to collect a long enough run time of data to sample a long period GW source with good statistics. Therefore, I think the odds are against finding such a source before 2030, but very good for finding one in the following decade.
[ edit: disregard - question is clear, I was confused].