Probing early structure formation with far-infrared background correlations

The large-scale structure of high-redshift galaxies produces correlated ani sotropy in the far-infrared background (FIRB). In regions of the sky where the thermal emission from Galactic dust is well below average, these high-r edshift correlations may be the most significant source of angular fluctuat ion power over a wide range of angular scales, from similar to7' to similar to3 degrees, and frequencies, from similar to 400 to similar to 1000 GHz. The strength of this signal should allow detailed studies of the statistics of the FIRB fluctuations, including the shape of the angular power spectru m at a given frequency and the degree of coherence between FIRB maps at dif ferent frequencies. The FIRB correlations depend on and hence constrain the redshift-dependent spectral energy distributions, number counts, and clust ering bias of the galaxies and active nuclei that contribute to the backgro und. We quantify the accuracy to which Planck and a newly proposed balloon- borne mission, Explorer of Diffuse Galactic Emissions, could constrain mode ls of the high-redshift universe through the measurement of FIRB fluctuatio ns. We conclude that the average bias of high-redshift galaxies could be me asured to an accuracy of less than or similar to 1% or, for example, separa ted into four redshift bins with similar to 10% accuracy.