The contribution of star-forming galaxies to fluctuations in the cosmic background light

Abstract

Star-forming galaxies which are too faint to be detected individually produce intensity fluctuations in the cosmic background light. This contribution needs to be taken into account as a foreground when using the primordial signal to constrain cosmological parameters. The extragalactic fluctuations are also interesting in their own right as they depend on the star formation history of the Universe and the way in which this connects with the formation of cosmic structure. We present a new framework which allows us to predict the occupation of dark matter haloes by star-forming galaxies and uses this information, in conjunction with an N-body simulation of structure formation, to predict the power spectrum of intensity fluctuations in the infrared background. We compute the emission from galaxies at far-infrared, millimetre and radio wavelengths. Our method gives accurate predictions for the clustering of galaxies both for the one halo and two halo terms. We illustrate our new framework using a previously published model which reproduces the number counts and redshift distribution of galaxies selected by their emission at $850\mu$m. Without adjusting any of the model parameters, the predictions show encouraging agreement at high frequencies and on small angular scales with recent estimates of the extragalactic fluctuations in the background made from early data analysed by the Planck Collaboration. There are, however, substantial discrepancies between the model predictions and observations on large angular scales and at low frequencies, which illustrates the usefulness of the intensity fluctuations as a constraint on galaxy formation models.

16 pages, 14 figures, Accepted version for MNRAS

References in corpus (13)

• A primer on hierarchical galaxy formation: the semi-analytical approach
• Generating Dark Matter Halo Merger Trees
• Astrophysical and Cosmological Information from Large-scale sub-mm Surveys of Extragalactic Sources
• Spitzer Deep and Wide Legacy Mid- and Far-Infrared Number Counts and Lower Limits of Cosmic Infrared Background
• Galaxy evolution in the infra-red: comparison of a hierarchical galaxy formation model with SPITZER data
• The assembly bias of dark matter haloes to higher orders
• Correlated Anisotropies in the Cosmic Far-Infrared Background Detected by MIPS/Spitzer: Constraint on the Bias
• Improved Models for Cosmic Infrared Background Anisotropies: New Constraints on the IR Galaxy Population
• Clustering of sub-millimeter galaxies in a self-regulated baryon collapse model
• Simulations of the cosmic infrared and submillimeter background for future large surveys: I. Presentation and first application to Herschel/SPIRE and Planck/HFI
• Modeling the evolution of infrared galaxies : clustering of galaxies in the Cosmic Infrared Background
• Anisotropy Studies of the Unresolved Far-infrared Background
• Power Spectrum Analysis of Far-IR Background Fluctuations in 160 Micron Maps From the Multiband Imaging Photometer for Spitzer

Cited by in corpus (8)

• A new model of galaxy formation: How sensitive are predicted galaxy luminosities to the choice of SPS model?
• A hybrid model for the evolution of galaxies and Active Galactic Nuclei in the infrared
• The redshift-evolution of the distribution of star formation among dark matter halos as seen in the infrared
• Clustering of sub-millimeter galaxies in a self-regulated baryon collapse model
• The spatial distribution of neutral hydrogen as traced by low HI mass galaxies
• The Clustering Evolution of Dusty Star-Forming Galaxies
• Cosmic dichotomy in the hosts of rapidly star-forming systems at low and high redshifts
• A hybrid multi resolution scheme to efficiently model the structure of reionization on the largest scales