CALURA, FrancescoFrancescoCALURAVANZELLA, ErosErosVANZELLACarniani, StefanoStefanoCarnianiGILLI, RobertoRobertoGILLIRosati, PieroPieroRosatiMENEGHETTI, MASSIMOMASSIMOMENEGHETTIPaladino, RositaRositaPaladinoDECARLI, ROBERTOROBERTODECARLIBrusa, MarcellaMarcellaBrusaLUPI, ALESSANDROALESSANDROLUPID'AMATO, QUIRINOQUIRINOD'AMATOBERGAMINI, PIETROPIETROBERGAMINICaminha, Gabriel B.Gabriel B.Caminha2022-05-272022-05-2720210035-8711http://hdl.handle.net/20.500.12386/32104We report on ALMA observations of D1, a system at z ∼ 6.15 with stellar mass M∼ 107M⊙ containing globular cluster (GC) precursors, stronglymagnified by the galaxy clusterMACS J0416.1-2403. Since the discovery of GC progenitors at high redshift, ours is the first attempt to probe directly the physical properties of their neutral gas through infrared observations. A careful analysis of our data set, performed with a suitable procedure designed to identify faint narrow lines and which can test various possible values for the unknown linewidth value, allowed us to identify a 4σ tentative detection of [CII] emission with intrinsic luminosity L[C II] = (2.9 ± 1.4) 106 L⊙, one of the lowest values ever detected at high redshift. This study offers a first insight on previously uncharted regions of the L[C II]-SFR relation. Despite large uncertainties affecting our measure of the star formation rate, if taken at face value our estimate lies more than ∼1 dex below the values observed in local and high redshift systems. Our weak detection indicates a deficiency of [C II] emission, possibly ascribed to various explanations, such as a low-density gas and/or a strong radiation field caused by intense stellar feedback, and a low metal content. From the non-detection in the continuum, we derive constraints on the dust mass, with 3σ upper limit values as low as ∼ a few 104 M⊙, consistent with the values measured in local metal-poor galaxies.STAMPAenConstraints on the [C II] luminosity of a proto-globular cluster at z ∼ 6 obtained with ALMAArticle10.1093/mnras/staa31852-s2.0-85098561415https://api.elsevier.com/content/abstract/scopus_id/85098561415https://academic.oup.com/mnras/article/500/3/3083/5925357?login=falseFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation