%AHazboun, Jeffrey%ACrump, Jack%ALommen, Andrea%AMontano, Sergio%ABerry, Samantha%AZeldes, Jesse%ATeng, Elizabeth%ARay, Paul%AKerr, Matthew%AArzoumanian, Zaven%ABogdanov, Slavko%ADeneva, Julia%ALewandowska, Natalia%AMarkwardt, Craig%ARansom, Scott%AEnoto, Teruaki%AWood, Kent%AGendreau, Keith%AHowe, David%AParthasarathy, Aditya%BJournal Name: The Astrophysical Journal; Journal Volume: 928; Journal Issue: 1; Related Information: CHORUS Timestamp: 2024-01-16 18:58:41 %D2022%IDOI PREFIX: 10.3847 %JJournal Name: The Astrophysical Journal; Journal Volume: 928; Journal Issue: 1; Related Information: CHORUS Timestamp: 2024-01-16 18:58:41 %K %MOSTI ID: 10366914 %PMedium: X; Size: Article No. 67 %TA Detection of Red Noise in PSR J1824–2452A and Projections for PSR B1937+21 Using NICER X-Ray Timing Data %X
We have used X-ray data from the Neutron Star Interior Composition Explorer (NICER) to search for long-timescale temporal correlations (“red noise”) in the pulse times of arrival (TOAs) from the millisecond pulsars PSR J1824−2452A and PSR B1937+21. These data more closely track intrinsic noise because X-rays are unaffected by the radio-frequency-dependent propagation effects of the interstellar medium. Our search yields strong evidence (natural log Bayes factor of 9.634 ± 0.016) for red noise in PSR J1824−2452A, but the search is inconclusive for PSR B1937+21. In the interest of future X-ray missions, we devise and implement a method to simulate longer and higher-precision X-ray data sets to determine the timing baseline necessary to detect red noise. We find that the red noise in PSR B1937+21 can be reliably detected in a 5 yr mission with a TOA error of 2