A Comparison of Nested Sampling Algorithm for Pulse Profile Modelling of PSR J0740 + 6620

In the last few years, NICER data has enabled mass and radius inferences for four pulsars: PSR J0030 + 0451, PSR J0437 - 4715, PSR J0740 + 6620, and PSR J1231 - 1411. These results are obtained via a technique called pulse profile modeling. Given their importance for constraining the equation of state of dense nuclear matter, it is necessary to validate and test their robustness. We use X-ray Pulse Simulation and Inference (X-PSI), an open-source package for pulse profile modeling and Bayesian statistical inference, to get mass and radius inferences. In this talk, I will discuss the effect of our sampler choice within X-PSI, focusing on the specific case of the high-mass pulsar PSR J0740 + 6620. I will discuss the effect of our sampler choice on the parameter recovery performance, convergence, computational cost, and most importantly, the implication on the mass-radius inference results of PSR J0740 + 6620.