Filaments of The Slime Mold Cosmic Web And How They Affect Galaxy Evolution

Farhanul Hasan; Joseph N. Burchett; Douglas Hellinger; Oskar Elek; Daisuke Nagai; S. M. Faber; Joel R. Primack; David C. Koo; Nir Mandelker; Joanna Woo

arXiv · 2311.01443

Filaments of The Slime Mold Cosmic Web And How They Affect Galaxy Evolution

Farhanul Hasan·Joseph N. Burchett·Douglas Hellinger·Oskar Elek·Daisuke Nagai·S. M. Faber·Joel R. Primack·David C. Koo·Nir Mandelker·Joanna Woo

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Abstract

We present a novel method for identifying cosmic web filaments using the IllustrisTNG (TNG100) cosmological simulations and investigate the impact of filaments on galaxies. We compare the use of cosmic density field estimates from the Delaunay Tessellation Field Estimator (DTFE) and the Monte Carlo Physarum Machine (MCPM), which is inspired by the slime mold organism, in the DisPerSE structure identification framework. The MCPM-based reconstruction identifies filaments with higher fidelity, finding more low-prominence/diffuse filaments and better tracing the true underlying matter distribution than the DTFE-based reconstruction. Using our new filament catalogs, we find that most galaxies are located within 1.5-2.5 Mpc of a filamentary spine, with little change in the median specific star formation rate and the median galactic gas fraction with distance to the nearest filament. Instead, we introduce the filament line density, Sigma_fil(MCPM), as the total MCPM overdensity per unit length of a local filament segment, and find that this parameter is a superior predictor of galactic gas supply and quenching. Our results indicate that most galaxies are quenched and gas-poor near high-line density filaments at z<=1. At z=0, quenching in log(M*/Msun)>10.5 galaxies is mainly driven by mass, while lower-mass galaxies are significantly affected by the filament line density. In high-line density filaments, satellites are strongly quenched, whereas centrals have reduced star formation, but not gas fraction, at z<=0.5. We discuss the prospect of applying our new filament identification method to galaxy surveys with SDSS, DESI, Subaru PFS, etc. to elucidate the effect of large-scale structure on galaxy formation.

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Farhanul Hasan, Joseph N. Burchett, Douglas Hellinger, Oskar Elek, Daisuke Nagai, S. M. Faber, Joel R. Primack, David C. Koo, Nir Mandelker, Joanna Woo. 2023-11-02. Filaments of The Slime Mold Cosmic Web And How They Affect Galaxy Evolution. https://arxiv.org/abs/2311.01443

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