| Title: |
Angular momentum profiles of Class 0 protostellar envelopes |
| Authors: |
Gaudel, Mathilde; Maury, Anaëlle; Belloche, Arnaud; Maret, Sébastien; André, Philippe; Hennebelle, Patrick; Galametz, Maud; Testi, Leonardo; Cabrit, Sylvie; Palmeirim, Pedro; Ladjelate, Bilal; Codella, Claudio; Podio, Linda |
| Contributors: |
Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)); Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité); Max-Planck-Institut für Radioastronomie (MPIFR); Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA); École normale supérieure - Paris (ENS-PSL); Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris; Centre National de la Recherche Scientifique (CNRS)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY); Harvard-Smithsonian Center for Astrophysics (CfA); Harvard University-Smithsonian Institution; Institut de Planétologie et d'Astrophysique de Grenoble (IPAG); Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (Fédération OSUG)-Université Grenoble Alpes (UGA); European Southern Observatory (ESO); Instituto de Astrofísica e Ciências do Espaço (IASTRO); Instituto de RadioAstronomía Milimétrica (IRAM); Centre National de la Recherche Scientifique (CNRS); INAF- Osservatorio Astrofisico di Arcetri (OAA); Istituto Nazionale di Astrofisica Rome (INAF); ANR-16-IDEX-0008,PSI,PSI(2016); European Project: 291294,ERC-2011-ADG_20110209,ERC-2011-ADG_20110209,ORISTARS(2012); European Project: 679937,ERC-2015-STG,ERC-2015-STG,MagneticYSOs(2016) |
| Source: |
ISSN: 0004-6361. |
| Publisher Information: |
CCSD; EDP Sciences |
| Publication Year: |
2020 |
| Collection: |
Université Paris Seine: ComUE (HAL) |
| Subject Terms: |
radio lines: ISM; ISM: kinematics and dynamics; stars: protostars; stars: formation; [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]; [PHYS]Physics [physics] |
| Description: |
International audience ; Context. Understanding the initial properties of star forming material and how they affect the star formation process is a key question. The infalling gas must redistribute most of its initial angular momentum inherited from prestellar cores before reaching the central stellar embryo. Disk formation has been naturally considered as a possible solution to this “angular momentum problem”. However, how the initial angular momentum of protostellar cores is distributed and evolves during the main accretion phase and the beginning of disk formation has largely remained unconstrained up to now.Aims. In the framework of the IRAM CALYPSO survey, we obtained observations of the dense gas kinematics that we used to quantify the amount and distribution of specific angular momentum at all scales in collapsing-rotating Class 0 protostellar envelopes.Methods. We used the high dynamic range C18O (2−1) and N2H+ (1−0) datasets to produce centroid velocity maps and probe the rotational motions in the sample of 12 envelopes from scales ~50 to ~5000 au.Results. We identify differential rotation motions at scales ≲1600 au in 11 out of the 12 protostellar envelopes of our sample by measuring the velocity gradient along the equatorial axis, which we fit with a power-law model v ∝ rα. This suggests that coherent motions dominate the kinematics in the inner protostellar envelopes. The radial distributions of specific angular momentum in the CALYPSO sample suggest the following two distinct regimes within protostellar envelopes: the specific angular momentum decreases as j ∝ r1.6±0.2 down to ~1600 au and then tends to become relatively constant around ~6 × 10−4 km s−1 pc down to ~50 au.Conclusions. The values of specific angular momentum measured in the inner Class 0 envelopes suggest that material directly involved in the star formation process ( |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
info:eu-repo/semantics/altIdentifier/arxiv/2001.10004; info:eu-repo/grantAgreement//291294/EU/Toward a Complete View of Star Formation: The Origin of Molecular Clouds, Prestellar Cores, and Star Clusters/ORISTARS; info:eu-repo/grantAgreement//679937/EU/Interpreting Dust Polarization Maps to Characterize the Role of the Magnetic Field in Star Formation Processes/MagneticYSOs; ARXIV: 2001.10004; BIBCODE: 2020A&A.637A.92G |
| DOI: |
10.1051/0004-6361/201936364 |
| Availability: |
https://cea.hal.science/cea-02644105; https://cea.hal.science/cea-02644105v2/document; https://cea.hal.science/cea-02644105v2/file/aa36364-19.pdf; https://doi.org/10.1051/0004-6361/201936364 |
| Rights: |
info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.A4A146C3 |
| Database: |
BASE |