Modelling Galaxy Clustering and Tomographic Galaxy-Galaxy Lensing with HSC Y3 and SDSS using the Point-Mass Correction Model and Redshift Self-Calibration
Cosmology and Nongalactic Astrophysics2025-07-28v2
The combination of galaxy-galaxy weak lensing and galaxy clustering is a powerful probe of the cosmological model, and exploration of how to best model and extract this information from the signals is essential. We present the measurement of the galaxy-galaxy weak lensing signals using the SDSS DR11 spectroscopic galaxies as lens galaxies, and the HSC Y3 shear catalog as source galaxies, binned into four tomographic bins by their photometric redshift. The SDSS DR11 galaxies, with a redshift range 0.15<z<0.7, are binned into three redshift bins, each as a probe for measuring the projected correlation function, wp(Rp). We measure the galaxy-galaxy lensing signal ΔΣ(Rp) in 12 lens-source bin pairs and show that there is no evidence for significant systematic biases in the measurement with null testing. We combine our wp(Rp) and ΔΣ(Rp) (2×2pt) data vectors and perform likelihood inference with a flat ΛCDM model. For ΔΣ(Rp), we extend the lower limit of the scale cut compared to previous HSC Y3 analyses to 2h−1Mpc by including a point-mass correction term in addition to the minimal bias model. We present various tests to validate our model and provide extended consistency tests. In the ΛCDM context, our fiducial model yields S8=0.804−0.051+0.051. The 2×2pt data vector provides redshift parameter constraints for the third and fourth redshift bins Δz3=−0.079−0.084+0.074, and Δz4=−0.203−0.206+0.167, which is consistent with results from the previous tomographic cosmic shear studies, and serves as the foundation for a future 3×2pt analysis.
@article{arxiv.2507.01377,
title = {Modelling Galaxy Clustering and Tomographic Galaxy-Galaxy Lensing with HSC Y3 and SDSS using the Point-Mass Correction Model and Redshift Self-Calibration},
author = {Tianqing Zhang and Sunao Sugiyama and Surhud More and Rachel Mandelbaum and Xiangchong Li and Roohi Dalal and Hironao Miyatake and Arun Kannawadi and Atsushi J. Nishizawa and Takahiro Nishimichi and Masamune Oguri and Ken Osato and Markus M. Rau and Masato Shirasaki and Tomomi Sunayama and Masahiro Takada},
journal= {arXiv preprint arXiv:2507.01377},
year = {2025}
}