8 papers
Constraining Pulsar Radiative Geometry via Multi-wavelength Modeling
Tong Zhao, Shunshun Cao, Renxin Xu
We propose that jointly modeling the thermal X-ray pulse profiles and the polarization position angles offers an effective means of locating the polarization orientation focus of t…
An Intrinsic Degeneracy in a Simplified Semi-Analytic Two-Spot Model for Thermal X-Ray Pulse-Profiles
Tong Zhao, Mingyu Ge, Renxin Xu
We identify an intrinsic degeneracy in the simplified semi-analytic two-spot model for parameter inference in thermal X-ray pulse-profile modeling. Although the exact algebraic deg…
Exploring the spin dependence on mass inclination and distance for the newly discovered black hole X-ray binary Swift J151857.0-572147
Yujia Song, James F. Steiner, Tong Zhao +7
The black hole X-ray binary (BHXRB) Swift J151857.0-572147 was discovered during its first outburst in March 2024. We review the archive of NICER observations from this outburst, f…
CSST Strong Lensing Preparation: Cosmological constraints from double-source-plane strong lensing systems in era of CSST
Bei-Chen Wu, Xiaoyue Cao, Nan Li +5
Double source plane strong lensing (DSPL) systems offer a robust, independent probe of cosmological parameters. The Chinese Space Station Telescope (CSST) is expected to discover h…
Limits to Extracting Neutron-Star Physics Constraints from NICER Pulse Profiles
Tolga Guver, Dimitrios Psaltis, Feryal Ozel +1
Modeling energy-dependent X-ray pulse profiles from rotation-powered millisecond pulsars observed with NICER has emerged as a promising avenue for measuring neutron star radii and…
Machine Learning Acceleration of Neutron Star Pulse Profile Modeling
Preston G. Waldrop, Dimitrios Psaltis, Tong Zhao
Ray tracing algorithms that compute pulse profiles from rotating neutron stars are essential tools for constraining neutron-star properties with data from missions such as NICER. H…