%0 Journal Article %T A 3mm chemical exploration of small organics in Class I YSOs %+ Umeå University %+ Institut de Planétologie et d'Astrophysique de Grenoble (IPAG) %+ Centre National d'Études Spatiales [Toulouse] (CNES) %A Le Gal, Romane %A Öberg, Karin, I %A Huang, Jane %A Ménard, François %A Lefloch, Bertrand %A Vastel, Charlotte %A Lopez-Sepulcre, Ana %A Favre, Cécile %A Bianchi, Eleonora %< avec comité de lecture %@ 0004-637X %J The Astrophysical Journal %I American Astronomical Society %V 898 %N 2 %P 131 %8 2020-06-24 %D 2020 %R 10.3847/1538-4357/ab9ebf %K YSOs: individual (IRAS 04181+2654A %K IRAS 04169+2702 %K IRAS 04166+2706 %K IRAS 04016+2610 %K IRAS 04365+2535 %K IRAS 04295+2251 %K IRAS 04302+2247) - %Z Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA]Journal articles %X There is mounting evidence that the composition and structure of planetary systems are intimately linked to their birth environments. During the past decade, several spectral surveys probed the chemistry of the earliest stages of star formation and of late planet-forming disks. However, very little is known about the chemistry of intermediate protostellar stages, i.e. Class I Young Stellar Objects (YSOs), where planet formation may have already begun. We present here the first results of a 3mm spectral survey performed with the IRAM-30m telescope to investigate the chemistry of a sample of seven Class I YSOs located in the Taurus star-forming region. These sources were selected to embrace the wide diversity identified for low-mass protostellar envelope and disk systems. We present detections and upper limits of thirteen small (N atoms ≤ 3) C, N, O, and S carriers-namely CO, HCO + , HCN, HNC, CN, N 2 H + , C 2 H, CS, SO, HCS + , C 2 S, SO 2 , OCS-and some of their D, 13 C, 15 N, 18 O, 17 O, and 34 S isotopologues. Together, these species provide constraints on gas-phase C/N/O ratios, D-and 15 N-fractionation, source temperature and UV exposure, as well as the overall S-chemistry. We find substantial evidence of chemical differentiation among our source sample, some of which can be traced back to Class I physical parameters, such as the disk-to-envelope mass ratio (proxy for Class I evolutionary stage), the source luminosity, and the UV-field strength. Overall, these first results allow us to start investigating the astrochemistry of Class I objects, however, interferometric observations are needed to differentiate envelope versus disk chemistry. %G English %2 https://cnrs.hal.science/hal-03008816/document %2 https://cnrs.hal.science/hal-03008816/file/2006.12526.pdf %L hal-03008816 %U https://cnrs.hal.science/hal-03008816 %~ INSU %~ METEO %~ UNIV-SAVOIE %~ UGA %~ CNRS %~ CNES %~ IPAG %~ INRAE %~ UGA-EPE %~ TEST3-HALCNRS