Thursday

I will present new deep and high resolution ALMA and HST/WC3 observations of luminous Lyman-alpha emitters (LAEs) in the epoch of re-ionisation at z~7: MASOSA, VR7 and CR7. We do not detect dust continuum in any of the LAEs, indicating little amounts of obscured star formation and/or high dust temperatures reaching up to 70-90K, even though MASOSA, the faintest in the UV, shows a red UV Beta slope. While VR7 and CR7 are strongly detected and resolved in multiple components in [CII], indicating clump metallicities of about 0.01-0.2 Z_sun, MASOSA is not detected in [CII], implying an even lower metallicity, consistent with its very compact size and extremely high Lyman-alpha EW. For both VR7 and CR7, we explore the rest-frame UV and [CII] sub-kpc resolved emission to find that the dynamics seen are consistent with merging: neither of the systems is rotation dominated. We also find clear evidence for outflows from [CII], large internal variations in the [CII]/UV ratio, and overall small velocity offsets between Lya and [CII], indicating that these sources reside in early ionised bubbles. I will conclude with commenting on how these sources fit into the general population of galaxies in the epoch of re-ionisation.