Improved models for cosmic infrared background anisotropies: new constraints on the infrared galaxy population

Abstract

The power spectrum of cosmic infrared background (CIB) anisotropies is sensitive to the connection between star formation and dark matter haloes over the entire cosmic star formation history. Here we develop a model that associates star‐forming galaxies with dark matter haloes and their subhaloes. The model is based on a parametrized relation between the dust‐processed infrared luminosity and (sub)halo mass. By adjusting three free parameters, we attempt to simultaneously fit the four frequency bands of the Planck measurement of the CIB anisotropy power spectrum. To fit the data, we find that the star formation efficiency must peak on a halo mass scale of ≈5 × 1012 M⊙ and the infrared luminosity per unit mass must increase rapidly with redshift. By comparing our predictions with a well‐calibrated phenomenological model for shot noise, and with a direct observation of source counts, we show that the mean duty cycle of the underlying infrared sources must be near unity, indicating that the CIB is dominated by long‐lived quiescent star formation, rather than intermittent short ‘starbursts’. Despite the improved flexibility of our model, the best simultaneous fit to all four Planck channels remains relatively poor. We discuss possible further extensions to alleviate the remaining tension with the data. Our model presents a theoretical framework for a future joint analysis of both background anisotropy and source count measurements.

Dusty star-forming galaxies at high redshift

“…These were based on earlier predictions related to the expected Herschel and Planck CIB fluctuations Amblard & Cooray (2007). Recent modeling, involving conditional luminosity functions (Cooray, 2006), have now improved these early conclusions (De Bernardis & Cooray, 2012;Viero et al, 2012;Shang et al, 2012;Xia et al, 2012). The most recent models of CIB anisotropy spectra find that the effective mass scale DSFGs are at the level of log M eff /M ∼ 12, consistent with the mass scale of dark matter halos where the star-formation efficiency is maximal Planck Collaboration et al, 2013b).…”

“…With halo mass and occupation number in hand, one can also infer connections between seemingly different populations of galaxies at high-z, as well as provide strong constraints on the theory of dusty galaxy formation (as discussed in § 10). In recent years the simple halo model has been improved with conditional luminosity functions (De Bernardis & Cooray, 2012;Viero et al, 2012;Shang et al, 2012;Xia et al, 2012) and with functions that take into account the mass-dependent duty cycle of DSFGs and the radius-dependent efficiency for halos to convert accreted baryons into stars in dark matter halos . In this subsection, we review the results from clustering measurements of different populations of dusty galaxies.…”

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…”

“…We can therefore define a differential emissivity dj ν /d log 10 M h (e.g. Shang et al 2012;Béthermin et al 2013) such that equation (16) can be expressed as…”

Tracing the Cosmological Evolution of Stars and Cold Gas with CMB Spectral Surveys

“…The correlation of the dust continuum with overdensity, across all pairs of frequency and galaxy survey redshift, is interesting in its own right as a decomposition of the CIB and its SED as a function of redshift (Serra et al 2014), and warrants future simulation work. The first approximation is to describe the CIB through its emissivity density using the model and parameters of Hall et al (2010) rather than through the luminosity function and underlying halo model (Shang et al 2012). The Limber integral then gives the three two-point correlations {C CIB×g , C gal , C CIB } between the CIB and the galaxy survey binned onto a slice.…”