Baryon effects on void statistics in the EAGLE simulation

RevMexAA (Serie de Conferencias), 00, 1–1 (2007)
ORAL CONTRIBUTION
BARYON EFFECTS ON VOID STATISTICS IN
THE EAGLE SIMULATION
Enrique Paillas1,2 , Claudia D.P. Lagos3 , Nelson
Padilla1,2 , Patricia Tissera4
Cosmic voids are promising tools for cosmological
tests due to their sensitivity to dark energy, modified gravity and alternative scenarios, such as massive neutrino cosmologies. Most previous studies in
the literature use cosmological N-body simulations
of dark matter particles that ignore the potential effect of baryonic physics. Here we analyse voids in
the matter and subhalo density field in the EAGLE
simulations, which follow the evolution of galaxies
in a ΛCDM universe with state-of-the-art subgrid
models of baryonic processes. We study the effect
of baryonic physics on the statistic of voids by comparing results with simulations that only follow the
evolution of dark matter, but use the same initial
condition as EAGLE. When using the mass in the
simulation, we do not find significant differences in
the abundance and mass/subhhalo density profiles
between voids in EAGLE and its dark matter-only
counterpart. However, voids traced by galaxies selected by a stellar mass cut have different properties
than voids traced by a sample of subhaloes with the
same number density in a dark matter-only simulation. Therefore, care must be taken when comparing
results from dark matter numerical simulations with
voids in the real universe traced by galaxies.
1
Instituto de Astrofı́sica, Pontificia Universidad Católica de
Chile, Av. Vicuña Mackenna 4860, Santiago, Chile. (epaillas
@astro.puc.cl).
2 Centro de Astro-Ingenierı́a, Pontificia Universidad Católica
de Chile, Av. Vicuña Mackenna 4860, Santiago, Chile.
3 International Centre for Radio Astronomy Research, 7 Fairway, Crawley, 6009, Perth, WA, Australia.
4 Departamento de Ciencias Fı́sicas, Universidad Andrés
Bello, Av. Republica 220, Santiago, Chile.
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