Abstract
The recent stochastic signal observed jointly by NANOGrav,parkes pulsar timing array,European pulsar timing array,and Chinese pulsar timing array can be accounted for by scalar-induced gravitational waves(SIGWs).The source of the SIGWs is from the primordial curvature perturbations,and the main contribution to the SIGWs is from the peak of the primordial curvature power spectrum.To effectively model this peak,we apply the Taylor expansion to parameterize it.With the Taylor expansion parameterization,we apply Bayesian methods to constrain the primordial curvature power spectrum based on the NANOGrav 15 year data set.The constraint on the primordial curvature power spectrum possesses a degree of generality,as the Taylor expansion can effectively approximate a wide range of function profiles.
基金项目
国家自然科学基金(12305060)
Talent-Introduction Program of Hubei Polytechnic University(19xjk25R)
NETL
NSTL
万方数据