We have recently developed a post-processing framework to estimate the abundance of atomic and molecular hydrogen (H i and H 2 , respectively) in galaxies in large-volume cosmological simulations. Here we compare the H i and H 2 content of IllustrisTNG galaxies to observations. We mostly restrict this comparison to z ≈ 0 and consider six observational metrics: the overall abundance of H i and H 2 , their mass functions, gas fractions as a function of stellar mass, the correlation between H 2 and star formation rate, the spatial distribution of gas, and the correlation between gas content and morphology. We find generally good agreement between simulations and observations, particularly for the gas fractions and the H i mass-size relation. The H 2 mass correlates with star formation rate as expected, revealing an almost constant depletion time that evolves up to z = 2 as observed. However, we also discover a number of tensions with varying degrees of significance, including an overestimate of the total neutral gas abundance at z = 0 by about a factor of two and a possible excess of satellites with no or very little neutral gas. These conclusions are robust to the modelling of the H i/H 2 transition. In terms of their neutral gas properties, the IllustrisTNG simulations represent an enormous improvement over the original Illustris run. All data used in this paper are publicly available as part of the IllustrisTNG data release.

We present here the analysis performed using the pyPipe3D pipeline for the final MaNGA data set included in the Sloan Digital Sky Survey data release 17. This data set comprises more than 10,000 individual data cubes, being the integral field spectroscopic (IFS) galaxy survey with the largest number of galaxies. pyPipe3D processes the IFS data cubes to extract spatially resolved spectroscopic properties of both the stellar population and the ionized gas emission lines. A brief summary of the properties of the sample and the characteristics of the analyzed data are included. The article provides details of: (i) the analysis performed; (ii) a description of the pipeline; (iii) the adopted stellar population library; (iv) the morphological and photometric analysis; (v) the adopted data model for the spatially resolved properties derived; and (vi) the individual integrated and characteristic galaxy properties included in the final catalog. Comparisons with the results from a previous version of the pipeline for earlier data releases and from other tools using this data set are included. A practical example of how to use the full data set and the final catalog illustrates how to handle the delivered product. Our full analysis can be accessed and downloaded from our web page.

We extend the local stellar galaxy-(sub)halo connection to the atomic hydrogen (H i) component by seeding semi-empirically galaxies into a large N-body dark matter (DM) simulation. The main input to construct the mock galaxy catalog are: our constrained stellar mass-to-(sub)halo circular velocity (M*–VDM) relation, assuming a scatter independent of any galaxy property, and the empirical $M_{\rm H\, \small {I}}$ conditional probability distributions given M* for central and satellite galaxies. We find that the $\langle \log {M_{\rm H\, \small {I}}}\rangle -\log {M_{\rm DM}}$ relation is not a monotonic increasing function. It increases with mass up to ${M_{\rm DM}}\sim 10^{12}$ M⊙, attaining a maximum of $\langle \log ({M_{\rm H\, \small {I}}}/{M_{\odot }})\rangle \sim 9.2$, and at higher (sub)halo masses, $\langle \log ({M_{\rm H\, \small {I}}})\rangle$ decreases slightly with MDM. The scatter around it is also large and mass dependent. The bivariate $M_{\rm H\, \small {I}}$ and MDM distribution is broad and bimodal, specially at ${M_{\rm DM}}\gtrsim 10^{12}$ M⊙, which is inherited from the input $M_{\rm H\, \small {I}}$ conditional distributions. We also report the total (central+satellites) H i gas mass within haloes, $M^{\rm tot}_{\rm H\, \small {I}}$, as a function of MDM. The mean ${M^{\rm tot}_{\rm H\, \small {I}}}$-${M_{\rm DM}}$ relation is an increasing monotonic function. The galaxy spatial clustering increases weakly as the $M_{\rm H\, \small {I}}$ threshold increases. Our H i mock galaxies cluster more in comparison to the blind H i ALFALFA survey but we show that it is mainly due to the selection effects. We discuss the implications of our results in the light of predictions from semi-analytical models and hydrodynamics simulations of galaxy evolution.

We report the bivariate $\rm HI$ - and $\rm H_{2}$ -stellar mass distributions of local galaxies in addition of an inventory of galaxy mass functions, MFs, for $\rm HI$ , $\rm H_{2}$ , cold gas, and baryonic mass, separately into early- and late-type galaxies. The MFs are determined using the $\rm HI$ and $\rm H_{2}$ conditional distributions and the galaxy stellar mass function (GSMF). For the conditional distributions we use the results from the compilation presented in Calette et al. [(2018) RMxAA, 54, 443.]. For determining the GSMF from $M_{*}\sim3\times10^{7}$ to $3\times10^{12}\ \text{M}_{\odot}$ , we combine two spectroscopic samples from the Sloan Digital Sky Survey at the redshift range $0.0033<z<0.2$ . We find that the low-mass end slope of the GSMF, after correcting from surface brightness incompleteness, is $\alpha\approx-1.4$ , consistent with previous determinations. The obtained $\rm HI\,$ MFs agree with radio blind surveys. Similarly, the $\rm H_{2}\,$ MFs are consistent with CO follow-up optically-selected samples. We estimate the impact of systematics due to mass-to-light ratios and find that our MFs are robust against systematic errors. We deconvolve our MFs from random errors to obtain the intrinsic MFs. Using the MFs, we calculate cosmic density parameters of all the baryonic components. Baryons locked inside galaxies represent 5.4% of the universal baryon content, while $\sim\! 96\%$ of the $\rm HI$ and $\rm H_{2}$ mass inside galaxies reside in late-type morphologies. Our results imply cosmic depletion times of $\rm H_{2}$ and total neutral H in late-type galaxies of $\sim\!1.3$ and 7.2 Gyr, respectively, which shows that late type galaxies are on average inefficient in converting $\rm H_{2}$ into stars and in transforming $\rm HI$ gas into $\rm H_{2}$ . Our results provide a fully self-consistent empirical description of galaxy demographics in terms of the bivariate gas–stellar mass distribution and their projections, the MFs. This description is ideal to compare and/or to constrain galaxy formation models.

muestras locales de galaxias que contienen información de la masa estelar, de HI y/o H 2 , y morfología. Procesamos adecuadamente la información relacionada con las no detecciones en gas y determinamos la relaciones de masa estelar a masa de HI y H 2 y sus dispersiones, tanto para galaxias tardías como tempranas. Las relaciones se describen por leyes simples o doble de potencias; las respectivos cocientes de masa H 2 a HI son presentados. Contreñimos también las distribuciones completas de los cocientes de masa de HI y H 2 a masa estelar, encontrando que se describen bien por una función de Schechter (galaxias tardías) y una función Schechter (cortada) + uniforme (galaxias tempranas). Usando la función de masa estelar y el cociente de galaxias tempranas a tardías en función de M * , estas distribuciones son mapeadas en funciones de masa de HI y H 2 . Las funciones de masa obtenidas son consistentes con aquellas inferidas de catastros. Las relaciones empíricas de masa de gas a estrellas y sus distribuciones para galaxias tardías/tempranas presentadas aquí pueden ser usadas para constreñir modelos y simulaciones de evolución de galaxias.