BLAST: CORRELATIONS IN THE COSMIC FAR-INFRARED BACKGROUND AT 250, 350, AND 500 μm REVEAL CLUSTERING OF STAR-FORMING GALAXIES

Abstract

We detect correlations in the cosmic far-infrared background due to the clustering of star-forming galaxies in observations made with the Balloon-borne Large Aperture Submillimeter Telescope, BLAST, at 250, 350, and 500 µm. We perform jackknife and other tests to confirm the reality of the signal. The measured correlations are well fit by a power law over scales of 5-25 arcminutes, with ∆I/I = 15.1 ± 1.7%. We adopt a specific model for submillimeter sources in which the contribution to clustering comes from sources in the redshift ranges 1.3 ≤ z ≤ 2.2, 1.5 ≤ z ≤ 2.7, and 1.7 ≤ z ≤ 3.2, at 250, 350 and 500 µm, respectively. With these distributions, our measurement of the power spectrum, P (k θ ), corresponds to linear bias parameters, b = 3.8 ± 0.6, 3.9 ± 0.6 and 4.4 ± 0.7, respectively. We further interpret the results in terms of the halo model, and find that at the smaller scales, the simplest halo model fails to fit our results. One way to improve the fit is to increase the radius at which dark matter halos are artificially truncated in the model, which is equivalent to having some star-forming galaxies at z ≥ 1 located in the outskirts of groups and clusters. In the context of this model we find a minimum halo mass required to host a galaxy is log(M min /M ⊙ ) = 11.5 +0.4 −0.1 , and we derive effective biases b eff = 2.2 ± 0.2, 2.4 ± 0.2, and 2.6 ± 0.2, and effective masses log(M eff /M ⊙ ) = 12.9 ± 0.3, 12.8 ± 0.2, and 12.7 ± 0.2 , at 250, 350 and 500 µm, corresponding to spatial correlation lengths of r 0 = 4.9, 5.0, and 5.2 ± 0.7 h −1 Mpc, respectively. Finally, we discuss implications for clustering measurement strategies with Herschel and Planck.

Planck2013 results. XV. CMB power spectra and likelihood

“…Further theoretical investigation (Scott & White 1999;Haiman & Knox 2000) was stimulated by the detection of the infrared background in the COBE data (Puget et al 1996;Fixsen et al 1998), and the detection of bright "sub-millimetre" galaxies in SCUBA data (Hughes et al 1998). Subsequently, the clustering has been detected at 160 microns , at 250, 350 and 500 microns by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST, Viero et al 2009;Hajian et al 2012) and at 217 GHz by SPT and ACT (Hall et al 2010;Dunkley et al 2011). Recent Planck measurements of the CIB (Planck Collaboration XVIII 2011) have extended the measurements at 217 GHz, 353 GHz, and 545 GHz to larger scales, and recent Herschel measurements (Viero et al 2013) have improved on the BLAST measurements and extended them to smaller angular scales.…”

The clustering evolution of dusty star-forming galaxies

“…Viero et al 2009;Shang et al 2012). Here χ is the radial comoving distance to redshift z, a = (1 + z) −1 is the cosmological scale factor and j ν (z) describes the mean emissivity per unit solid angle at redshift z, which can be expressed as…”

“…More recently studies have been able to measure a clear signal (e.g. Viero et al 2009;Amblard et al 2011;Viero et al 2013;Planck Collaboration XXX 2014), though significant modelling is required in order to interpret these results in terms of halo masses. The Viero et al (2013) and Plank Collaboration studies infer the typical halo mass for galaxies that dominate the CIB power spectrum as 10 11.95 ± 0.5 h −1 M and 10 12.43 ± 0.1 h −1 M , respectively, making various assumptions such as the form of the relationship between galaxy luminosity and halo mass being independent of redshift, and that this relationship is the same for both central and satellite galaxies.…”

A comparison of algorithms for the construction of SZ cluster catalogues

“…As for the foreground model, the templates used to model Galactic components in the PSM were chosen so that they are reasonably representative of the complexity of the diffuse galactic emission. Thanks to many new observations in particular in the IR and submm domain Viero et al 2009;Hall et al 2010;Amblard et al 2011;Planck Collaboration 2011d), the models of point sources have evolved very much between the beginning of the SZ challenge and the publication of these results. These updates were not taken into account in the PSM when the study was performed.…”