Paper detail

The Contribution of Galaxies to the $3.4\,\mathrm{μm}$ Cosmic Infrared Background as Measured Using WISE

The study of the extragalactic background light (EBL) in the optical and near infrared has received a lot of attention in the last decade, especially near a wavelength of $λ\approx 3.4\operatorname{μm}$, with remaining tension among different techniques for estimating the background. In this paper we present a measurement of the contribution of galaxies to the EBL at $3.4\operatorname{μm}$ that is based on the measurement of the luminosity function (LF) in Lake et al. (2018) and the mean spectral energy distribution of galaxies in Lake & Wright (2016). The mean and standard deviation of our most reliable Bayesian posterior chain gives a $3.4\operatorname{μm}$ background of $I_ν= 9.0\pm0.5 \operatorname{kJy} \operatorname{sr}^{-1}$ ($νI_ν= 8.0\pm0.4 \operatorname{nW} \operatorname{m}^{-2} \operatorname{sr}^{-1} e\operatorname{-fold}^{-1}$), with systematic uncertainties unlikely to be greater than $2\operatorname{kJy} \operatorname{sr}^{-1}$. This result is higher than most previous efforts to measure the contribution of galaxies to the $3.4\operatorname{μm}$ EBL, but is consistent with the upper limits placed by blazars and the most recent direct measurements of the total $3.4\operatorname{μm}$ EBL.