We contrast predictions for the high-redshift galaxy population and
reionization history between Cold Dark Matter (CDM) and an alternative DM model
based on the recently developed ETHOS framework (Effective Theory of Structure
Formation; Cyr-Racine et al. 2016, Vogelsberger et al. 2016). We focus on an
ETHOS model that alleviates the small-scale CDM challenges within the Local
Group, and perform the currently highest resolution hydrodynamical volume
$\sim$ (36 Mpc)$^3$ simulations within ETHOS and CDM combined with the
IllustrisTNG galaxy formation model (gas cell mass $\sim10^5M_ødot$, gas
softening $\sim$ 180 pc) to quantify the abundance of galaxies at high redshift
and their impact on reionisation. While current observations of high-redshift
luminosity functions cannot differentiate between ETHOS and CDM, deep JWST
surveys of strongly-lensed, inherently faint galaxies could potentially detect
or constrain a primordial cutoff in the power spectrum. We find that ETHOS
galaxies have higher ultraviolet (UV) luminosities than their CDM counterparts
and a faster build up of the fainter end of the UV luminosity function; a
distinct behaviour offering a promising avenue to identify a primordial power
spectrum cutoff. This effect, however, makes the optical depth to reionisation
less sensitive to this cutoff, such that the ETHOS model differs from the CDM
$\tau$ value by only 10% and is consistent with Planck limits, as long as the
effective escape fraction is in the 0.1 -- 0.5 range. We conclude that high
redshift observations in the JWST era have the potential to probe non-CDM
models that offer attractive solutions to the Local Group CDM problems.
Description
[1711.10497] ETHOS -- an effective theory of structure formation: Predictions for the high-redshift Universe -- abundance of galaxies and reionization
%0 Generic
%1 lovell2017ethos
%A Lovell, Mark R.
%A Zavala, Jesús
%A Vogelsberger, Mark
%A Shen, Xuejian
%A Cyr-Racine, Francis-Yan
%A Pfrommer, Christoph
%A Sigurdson, Kris
%A Boylan-Kolchin, Michael
%A Pillepich, Annalisa
%D 2017
%K cold dark matter reionization simulations warm
%T ETHOS -- an effective theory of structure formation: Predictions for the
high-redshift Universe -- abundance of galaxies and reionization
%U http://arxiv.org/abs/1711.10497
%X We contrast predictions for the high-redshift galaxy population and
reionization history between Cold Dark Matter (CDM) and an alternative DM model
based on the recently developed ETHOS framework (Effective Theory of Structure
Formation; Cyr-Racine et al. 2016, Vogelsberger et al. 2016). We focus on an
ETHOS model that alleviates the small-scale CDM challenges within the Local
Group, and perform the currently highest resolution hydrodynamical volume
$\sim$ (36 Mpc)$^3$ simulations within ETHOS and CDM combined with the
IllustrisTNG galaxy formation model (gas cell mass $\sim10^5M_ødot$, gas
softening $\sim$ 180 pc) to quantify the abundance of galaxies at high redshift
and their impact on reionisation. While current observations of high-redshift
luminosity functions cannot differentiate between ETHOS and CDM, deep JWST
surveys of strongly-lensed, inherently faint galaxies could potentially detect
or constrain a primordial cutoff in the power spectrum. We find that ETHOS
galaxies have higher ultraviolet (UV) luminosities than their CDM counterparts
and a faster build up of the fainter end of the UV luminosity function; a
distinct behaviour offering a promising avenue to identify a primordial power
spectrum cutoff. This effect, however, makes the optical depth to reionisation
less sensitive to this cutoff, such that the ETHOS model differs from the CDM
$\tau$ value by only 10% and is consistent with Planck limits, as long as the
effective escape fraction is in the 0.1 -- 0.5 range. We conclude that high
redshift observations in the JWST era have the potential to probe non-CDM
models that offer attractive solutions to the Local Group CDM problems.
@misc{lovell2017ethos,
abstract = {We contrast predictions for the high-redshift galaxy population and
reionization history between Cold Dark Matter (CDM) and an alternative DM model
based on the recently developed ETHOS framework (Effective Theory of Structure
Formation; Cyr-Racine et al. 2016, Vogelsberger et al. 2016). We focus on an
ETHOS model that alleviates the small-scale CDM challenges within the Local
Group, and perform the currently highest resolution hydrodynamical volume
$\sim$ (36 Mpc)$^3$ simulations within ETHOS and CDM combined with the
IllustrisTNG galaxy formation model (gas cell mass $\sim10^5M_{\odot}$, gas
softening $\sim$ 180 pc) to quantify the abundance of galaxies at high redshift
and their impact on reionisation. While current observations of high-redshift
luminosity functions cannot differentiate between ETHOS and CDM, deep JWST
surveys of strongly-lensed, inherently faint galaxies could potentially detect
or constrain a primordial cutoff in the power spectrum. We find that ETHOS
galaxies have higher ultraviolet (UV) luminosities than their CDM counterparts
and a faster build up of the fainter end of the UV luminosity function; a
distinct behaviour offering a promising avenue to identify a primordial power
spectrum cutoff. This effect, however, makes the optical depth to reionisation
less sensitive to this cutoff, such that the ETHOS model differs from the CDM
$\tau$ value by only 10% and is consistent with Planck limits, as long as the
effective escape fraction is in the 0.1 -- 0.5 range. We conclude that high
redshift observations in the JWST era have the potential to probe non-CDM
models that offer attractive solutions to the Local Group CDM problems.},
added-at = {2017-11-30T14:52:14.000+0100},
author = {Lovell, Mark R. and Zavala, Jesús and Vogelsberger, Mark and Shen, Xuejian and Cyr-Racine, Francis-Yan and Pfrommer, Christoph and Sigurdson, Kris and Boylan-Kolchin, Michael and Pillepich, Annalisa},
biburl = {https://www.bibsonomy.org/bibtex/2a52c783463c550e718e13ac244cff23e/miki},
description = {[1711.10497] ETHOS -- an effective theory of structure formation: Predictions for the high-redshift Universe -- abundance of galaxies and reionization},
interhash = {35e1635a928e74dfecc6cd7eb607dece},
intrahash = {a52c783463c550e718e13ac244cff23e},
keywords = {cold dark matter reionization simulations warm},
note = {cite arxiv:1711.10497Comment: 15 pages, 8 figures, to be submitted to MNRAS. Please contact lovell@hi.is with any comments},
timestamp = {2017-11-30T14:52:14.000+0100},
title = {ETHOS -- an effective theory of structure formation: Predictions for the
high-redshift Universe -- abundance of galaxies and reionization},
url = {http://arxiv.org/abs/1711.10497},
year = 2017
}