Diffuse extragalactic background light versus deep galaxy counts in the Subaru deep field: Missing light in the universe?

Deep optical and near-infrared galaxy counts are utilized to estimate the e xtragalactic background light (EBL) coming from normal galactic light in th e universe. Although the slope of the number-magnitude relation of the fain test counts is flat enough for the count integration to converge, a conside rable fraction of EBL from galaxies could still have been missed in deep ga laxy surveys because of various selection effects, including the cosmologic al dimming of the surface brightness of galaxies. Here we give an estimate of EBL from galaxy counts, in which these selection effects are quantitativ ely taken into account for the first time, based on reasonable models of ga laxy evolution that are consistent with all available data of galaxy counts , size, and redshift distributions. We show that the EBL from galaxies is b est resolved into discrete galaxies in the near-infrared bands (J, K) by us ing the latest data of the Subaru Deep Field; more than 80%-90% of EBL from galaxies has been resolved in these bands. Our result indicates that the c ontribution by missing galaxies cannot account for the discrepancy between the count integration and recent tentative detections of diffuse EBL in the K band (2.2 mum), and there may be a very diffuse component of EBL that ha s left no imprints in known galaxy populations.