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Extreme emission-line galaxies (EELGs) at redshift z=1-2 provide a unique view of metal-poor, starburst sources that are the likely drivers of the cosmic reionization at z$geq6$. However, the molecular gas reservoirs of EELGs - the fuel for their intense star-formation - remain beyond the reach of current facilities. We present ALMA [CII] and PdBI CO(2-1) observations of a z=1.8, strongly lensed EELG SL2S 0217, a bright Lyman-$alpha$ emitter with a metallicity 0.05 $Z_odot$. We obtain a tentative (3-4$sigma$) detection of the [CII] line and set an upper limit on the [CII]/SFR ratio of $leq1times10^6$ $L_odot$/($M_odot$ yr$^{-1}$), based on the synthesized images and visibility-plane analysis. The CO(2-1) emission is not detected. Photoionization modelling indicates that up to 80% of the [CII] emission originates from neutral or molecular gas, although we can not rule out that the gas is fully ionized. The very faint [CII] emission is in line with both nearby metal-poor dwarfs and high-redshift Lyman-$alpha$ emitters, and predictions from hydrodynamical simulations. However, the [CII] line is 30$times$ fainter than predicted by the De Looze et al. [CII]-SFR relation for local dwarfs, illustrating the danger of extrapolating locally-calibrated relations to high-redshift, metal-poor galaxies.
We present deep spectroscopic observations of a Lyman-break galaxy candidate (hereafter MACS1149-JD) at $zsim9.5$ with the $textit{Hubble}$ Space Telescope ($textit{HST}$) WFC3/IR grisms. The grism observations were taken at 4 distinct position angle
We present chemical abundance measurements of three stars in the ultra-faint dwarf galaxy Horologium I, a Milky Way satellite discovered by the Dark Energy Survey. Using high resolution spectroscopic observations we measure the metallicity of the thr
We present the results of ALMA spectroscopic follow-up of a $z=6.765$ Lyman-$alpha$ emitting galaxy behind the cluster RXJ1347-1145. We report the detection of [CII]158$mu$m line fully consistent with the Lyman-$alpha$ redshift and with the peak of t
Local extremely metal-poor (XMP) galaxies are of particular astrophysical interest since they allow us to look into physical processes characteristic of the early Universe, from the assembly of galaxy disks to the formation of stars in conditions of
Our objectives are to determine the properties of the interstellar medium (ISM) and of star-formation in typical star-forming galaxies at high redshift. Following up on our previous multi-wavelength observations with HST, Spitzer, Herschel, and the P