THE CLUSTERING CHARACTERISTICS OF H i-SELECTED GALAXIES FROM THE 40% ALFALFA SURVEY

By Ann M. Martin, R. Giovanelli, M. Haynes, L. Guzzo. 2012

62 citations recorded by the source corpus.

The 40% Arecibo Legacy Fast ALFA survey catalog (α.40) of ∼10,150 H i-selected galaxies is used to analyze the clustering properties of gas-rich galaxies. By employing the Landy–Szalay estimator and a full covariance analysis for the two-point galaxy–galaxy correlation function, we obtain the real-space correlation function and model it as a power law, ξ(r) = (r/r0)−γ, on scales <10 h−1 Mpc. As the largest sample of blindly H i-selected galaxies to date, α.40 provides detailed understanding of the clustering of this population. We find γ = 1.51 ± 0.09 and r0 = 3.3 + 0.3, −0.2 h−1 Mpc, reinforcing the understanding that gas-rich galaxies represent the most weakly clustered galaxy population known; we also observe a departure from a pure power-law shape at intermediate scales, as predicted in ΛCDM halo occupation distribution models. Furthermore, we measure the bias parameter for the α.40 galaxy sample and find that H i galaxies are severely antibiased on small scales, but only weakly antibiased on large scales. The robust measurement of the correlation function for gas-rich galaxies obtained via the α.40 sample constrains models of the distribution of H i in simulated galaxies, and will be employed to better understand the role of gas in environmentally dependent galaxy evolution.

Subfields: Astronomy and Astrophysics, Instrumentation, Statistical and Nonlinear Physics

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. M. Haynes
2. R. Giovanelli
3. Shan Huang
4. E. Papastergis
5. A. Cattaneo
6. J. Brinchmann
7. G. Hallenbeck
8. R. Koopmann

In Instrumentation

1. M. Haynes
2. R. Giovanelli
3. Shan Huang
4. E. Papastergis
5. J. Brinchmann
6. A. Cattaneo
7. J. Silk
8. D. Stark

In Statistical and Nonlinear Physics

1. E. Papastergis
2. Shan Huang
3. J. Silk
4. M. Haynes
5. R. Giovanelli
6. R. Battye
7. G. Mamon

Citations in the corpus

• H i intensity mapping: a single dish approach (2012, background): “We will assume, for the purposes of this discussion, that b = 1 independent of redshift, z, and scale k. Martin et al. (2012) find that this is a good assumption for scales > 10h−1 Mpc implying that, within the constraints of their survey, that HI galaxies trace the large-scale structure of the…”
• The Arecibo Legacy Fast ALFA Survey: The ALFALFA Extragalactic H i Source Catalog (2018, methodology): “As the least clustered local (z ∼ 0) galaxy population (Martin et al. 2012), the HI-bearing population traces how galaxies evolve when left on their own, in relative isolation.”
• THE ARECIBO LEGACY FAST ALFA SURVEY: THE GALAXY POPULATION DETECTED BY ALFALFA (2012, background): “Furthermore, analysis of the spatial correlation function ξ(r) shows that the HI-selected galaxies represent the least clustered population on small scales (Martin et al. 2012), a fact important for interpreting the results of future HI inte - sity mapping experiments.”
• The current status of galaxy formation (2012, background): “…and 21 cm surveys, on the one hand (for example, deep blind HI surveys show that gas-rich galaxies are the least clustered of any galaxy population Martin et al., 2012), and on the other hand, of questioning the details of hitherto inadequately modelled baryonic physics, as developed for example…”
• A DIRECT MEASUREMENT OF THE BARYONIC MASS FUNCTION OF GALAXIES AND IMPLICATIONS FOR THE GALACTIC BARYON FRACTION (2012, background): “We do not attempt to correct for blending but, given that HI-selected galaxies are a weakly clustered population (e.g. Martin et al. 2012), we anticipate the effect on the HI-selected distributions to be small.”