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We present the detection of Ly α, [O iii], and H α emission associated with an extremely strong damped Lyman-α (DLA) system (N(H i) = 10 22.10 cm −2 ) at z = 2.207 towards the quasar SDSS J113520.39−001053.56. This is the largest H i column density ever measured along a quasi-stellar object (QSO) line of sight, though typical of those often found in DLAs associated to gamma-ray bursts (GRBs). This absorption system can also be classified as an ultra-strong Mg ii system with W λ2796 , and is unresolved. From the H α line, we measure a significant star formation rate (SFR) ≈ 25 M yr −1 (uncorrected for dust). The shape of the Ly α line is double-peaked, which is the signature of a resonant scattering of Ly α photons, and the Ly α emission is spatially extended. More strikingly, the blue and red Ly α peaks arise from distinct regions extended over a few kpc on either side of the star-forming region. We propose that this is the consequence of a Ly α transfer in outflowing gas. The presence of starburst-driven outflows is also in agreement with the high SFR together with the small size and low mass of the galaxy (M vir ∼ 10 10 M ). By placing constraints on the stellar UV continuum luminosity of the galaxy, we estimate an age of at most a few 10 7 yr, again consistent with a recent starburst scenario. We interpret these data as the observation of a young, gas-rich, compact starburst galaxy, from which material is expelled through collimated winds powered by the vigorous star formation activity. We substantiate this picture by modelling the radiative transfer of Ly α photons in the galactic counterpart. Though our model (a spherical galaxy with bipolar outflowing jets) is a simplistic representation of the true gas distribution and velocity field, the agreement between the observed and simulated properties is particularly good (spectral shape and width of the Lyman-α emission, spatial configuration, escape fraction as well as absorption kinematics, H i column density, and dust reddening). Finally, we propose that selecting DLAs with very high H i column densities may be an efficient way of detecting star-forming galaxies at small impact parameters from the background QSO lines of sight.

Binary formation is an important aspect of star formation. One possible route for close-in binary formation is disk fragmentation [1,2,3] . Recent observations show small scale asymmetries (<300 au) around young protostars [2,4] , although not always resolving the circumbinary disk, are linked to disk phenomena [5,6] . In later stages, resolved circumbinary disk observations [7] (<200 au) show similar asymmetries, suggesting the origin of the asymmetries arises from binary-disk interactions [8,9,10] . We observed one of the youngest systems to study the connection between disk and dense core. We find for the first time a bright and clear streamer in chemically fresh material (Carbon-chain species) that originates from outside the dense core (>10,500 au). This material connects the outer dense core with the region where asymmetries arise near disk scales. This new structure type, 10x larger than those seen near disk scales, suggests a different interpretation of previous observations: largescale accretion flows funnel material down to disk scales. These results reveal the underappreciated importance of the local environment on the formation and evolution of disks in early systems [13,14] and a possible initial condition for the formation of annular features in young disks [15,16] .

We present the first results from a new, high resolution, 12 CO(1-0), 13 CO(1-0), and C 18 O(1-0) molecular line survey of the Orion A cloud, hereafter referred to as the CARMA-NRO Orion Survey. CARMA observations have been combined with single-dish data from the Nobeyama 45m telescope to provide extended images at about 0.01 pc resolution, with a dynamic range of approximately 1200 in spatial scale. Here we describe the practical details of the data combination in uv space, including flux scale matching, the conversion of single dish data to visibilities, and joint deconvolution of single dish and interferometric data. A ∆-variance analysis indicates that no artifacts are caused by combining data from the two instruments. Initial analysis of the data cubes, including moment maps, average spectra, channel maps, position-velocity diagrams, excitation temperature, column density, and line ratio maps provides evidence of complex and interesting structures such as filaments, bipolar outflows, shells, bubbles, and photo-eroded pillars. The implications for star formation processes are profound and follow-up scientific studies by the CARMA-NRO Orion team are now underway. We plan to make all the data products described here generally accessible; some are already available at [https://dataverse.harvard.edu/dataverse/CARMA-NRO-Orion].