Leaving the Dark Ages With Amiga

Abstract

We present an Analytic Model of Intergalactic-medium and GAlaxy evolution since the dark ages. AMIGA is in the spirit of the popular semi-analytic models of galaxy formation, although it does not use halo merger trees but interpolates halo properties in grids that are progressively built. This strategy is less memory-demanding and allows one to start the modeling at redshifts high enough and halo masses low enough to have trivial boundary conditions. The number of free parameters is minimized by making the causal connection between physical processes usually treated as independent from each other, which leads to more reliable predictions. But the strongest points of AMIGA are: i) the inclusion of molecular cooling and metal-poor, population III (Pop III) stars, with the most dramatic feedback, and ii) the accurate follow-up of the temperature and volume filling factor of neutral, singly, and doubly ionized regions, taking into account the distinct halo mass functions in those environments. We find the following general results. Massive Pop III stars determine the IGM metallicity and temperature, and the growth of spheroids and disks is self-regulated by that of massive black holes developed from the remnants of those stars. Yet, the properties of normal galaxies and active galactic nuclei appear to be quite insensitive to Pop III star properties owing to the much higher yield of ordinary stars compared to Pop III stars and the dramatic growth of MBHs when normal galaxies begin to develop, which cause the memory loss of the initial conditions. Subject headings: galaxies -galaxies: formation -dark matter -intergalactic medium 1 Even though current simulations start at z > ∼ 100, convergence of galaxy properties is only found up to z ∼ 7 for the most favorable case of relatively low resolutions (Schaye et al. 2010).

Constraining Reionization with the z ∼ 5–6 Lyα Forest Power Spectrum: The Outlook after Planck

“…Finally, given that there are few observables that are sensitive to the thermal state of baryons at the earliest redshifts, the 1D flux power spectrum at z 5 offers a unique opportunity to explore not only H i reionization, but also constrain other physical scenarios that alter the thermal history of the IGM, for example, models that alter the thermal state of the IGM via X-ray preheating coming from starburst galaxies, supernova remnants or miniquasars (Oh 2001;Glover & Brand 2003;Madau et al 2004;Furlanetto 2006;Madau & Fragos 2017), dark matter annihilation or decay (Liu et al 2016), cosmic rays (Samui et al 2005), blazar heating (Chang et al 2012;Puchwein et al 2012), broadband intergalactic dust absorption (Inoue & Kamaya 2008) or high-z exotic reionization scenarios driven by Population III stars (e.g. Manrique et al 2015).…”

On the multiplicity of ALMA Compact Array counterparts of far-infrared bright quasars

“…To check this idea, we run the self-consistent Analytic Model of Intergalactic-medium and GAlaxy (AMIGA; Manrique et al 2015) which successfully recovers the observed properties of the high-z universe (Salvador-Solé et al 2017). The idea is not to do an in-depth study of the results of the run, as this will be part of a dedicated upcoming work, but rather to simply test whether there is any theoretical support for such a claim.…”

An Improved Treatment of Cosmological Intergalactic Medium Evolution

“…To check the performance of this improved treatment of IGM we coupled it to the galaxy model by Manrique et al (2015) for realistic values of the parameters leading to double reionization (Salvador-Solé & Manrique 2014). The main results were as follows:…”

“…The aim of the present paper is to improve the analytical treatment of IGM evolution by deriving new more accurate master equations for its ionization state and temperature, and by estimating the halo ionization-bias necessary to properly compute the source functions in these equations. Such an improved treatment of IGM can be incorporated into any given (semi)numerical or (semi)analytic model of galaxy formation such as the one developed by Manrique et al (2015). The IGM properties shown throughout the paper to illustrate the effects of the new treatment have been obtained from that model.…”