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arXiv · 2411.00108

Baryon Pasting the Uchuu Lightcone Simulation

Erwin T. Lau·Daisuke Nagai·Arya Farahi·Tomoaki Ishiyama·Hironao Miyatake·Ken Osato·Masato Shirasaki
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Abstract

We present the Baryon Pasted (BP) X-ray and thermal Sunyaev-Zel'dovich (tSZ) maps derived from the half-sky Uchuu Lightcone simulation. These BP-Uchuu maps are constructed using more than $75$ million dark matter halos with masses $M_{500c} \geq 10^{13} M_\odot$ within the redshift range $0 \leq z \leq 2$. A distinctive feature of our BP-Uchuu Lightcone maps is their capability to assess the influence of both extrinsic and intrinsic scatter caused by triaxial gaseous halos and internal gas characteristics, respectively, at the map level. We show that triaxial gas drives substantial scatter in X-ray luminosities of clusters and groups, accounting for nearly half of the total scatter in core-excised measurements. Additionally, scatter in the thermal pressure and gas density profiles of halos enhances the X-ray and SZ power spectra, leading to biases in cosmological parameter estimates. These findings are statistically robust due to the extensive sky coverage and large halo sample in the BP-Uchuu maps. The BP-Uchuu maps are publicly available on https://app.globus.org/file-manager?origin_id=cf8dadb7-b6e9-4e2c-abc1-0813877efc13 .

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Erwin T. Lau, Daisuke Nagai, Arya Farahi, Tomoaki Ishiyama, Hironao Miyatake, Ken Osato, Masato Shirasaki. 2024-10-31. Baryon Pasting the Uchuu Lightcone Simulation. https://doi.org/10.3847/1538-4357%2Fada940

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