SIMBAD references

We combine information from the clustering of H I galaxies in the 100 per cent data release of the Arecibo Legacy Fast ALFA survey, and from the H I content of optically selected galaxy groups found in the Sloan Digital Sky Survey to constrain the relation between halo mass M_h and its average total H I mass content M_H I_. We model the abundance and clustering of neutral hydrogen through a halo-model-based approach, parametrizing the M_H I_(Mh_) relation as a power law with an exponential mass cut-off. To break the degeneracy between the amplitude and low-mass cut-off of the M_H I_(Mh_) relation, we also include a recent measurement of the cosmic H I abundance from the α.100 sample. We find that all data sets are consistent with a power-law index α = 0.48 ± 0.08 and a cut-off halo mass log₁₀M_ min_/(h^–1 M_☉)=11.18+0.28^_–0.35. We compare these results with predictions from state-of-the-art magnetohydrodynamical simulations, and find both to be in good qualitative agreement, although the data favours a significantly larger cut-off mass that is consistent with the higher cosmic H I abundance found in simulations. Both data and simulations seem to predict a similar value for the H I bias (b_ H I_=0.878+0.022^_–0.023) and shot-noise power (P_ SN₌₉₄+20^_–18 [h^–1 Mpc]^3) at redshift z = 0.