Pulsar Timing Array Based Search for Supermassive Black Hole Binaries in the Square Kilometer Array Era

Area of Science:

• Astrophysics
• Cosmology
• Gravitational Wave Astronomy

Background:

• Next-generation radio telescopes like the Square Kilometer Array (SKA) will significantly expand pulsar timing array (PTA) capabilities.
• Existing PTAs utilize dozens of pulsars, while future SKA-era PTAs will incorporate hundreds, posing data analysis challenges.

Purpose of the Study:

• To realistically assess the performance of a SKA-era PTA for detecting gravitational waves (GWs).
• To evaluate the data analysis challenges associated with an increased number of pulsar phase parameters.
• To specifically assess the search for isolated supermassive black hole binaries (SMBHBs).

Main Methods:

• Simulated a SKA-era PTA with 10^3 pulsars.
• Developed data analysis strategies to manage the expanded parameter space.
• Performed an all-sky search for nonevolving supermassive black hole binary sources.

Main Results:

• The SKA-era PTA can detect nonevolving SMBHBs with a redshifted chirp mass of 10^10 solar masses out to a redshift of 28.
• This corresponds to a rest-frame chirp mass detection limit of 3.4 x 10^8 solar masses.
• An upper limit on strain amplitude improvement of approximately 3 orders of magnitude is achievable.

Conclusions:

• SKA-era PTAs will revolutionize GW astronomy, particularly for SMBHB detection.
• The enhanced sensitivity and reach will provide crucial insights into SMBHB populations.
• Even in the absence of detections, significant improvements in GW strain limits will be achieved.