The APEX Large CO Heterodyne Orion Legacy Survey (ALCOHOLS): I. Survey overview
Artikel i vetenskaplig tidskrift, 2022

Context. The Orion molecular cloud complex harbours the nearest Giant Molecular Clouds (GMCs) and the nearest site of high-mass star formation. Its young star and protostar populations are thoroughly characterized. The region is therefore a prime target for the study of star formation.
Aims. Here, we verify the performance of the SuperCAM 64 pixel heterodyne array on the Atacama Pathfinder Experiment (APEX). We give a descriptive overview of a set of wide-field CO(32) spectral line cubes obtained towards the Orion GMC complex, aimed at characterizing the dynamics and structure of the extended molecular gas in diverse regions of the clouds, ranging from very active sites of clustered star formation in Orion B to comparatively quiet regions in southern Orion A. In a future publication, we will characterize the full population of protostellar outflows and their feedback over an entire GMC.
Methods. We present a 2.7 square degree (130 pc2) mapping survey in the 12CO(32) transition, obtained using SuperCAM on APEX at an angular resolution of 19 (7600 AU or 0.037 pc at a distance of 400 pc), covering the main sites of star formation in the Orion B cloud (L 1622, NGC 2071, NGC 2068, Ori B9, NGC 2024, and NGC 2023), and a large patch in the southern part of the L 1641 cloud in Orion A.
Results. We describe CO integrated line emission and line moment maps and position-velocity diagrams for all survey fields and discuss a few sub-regions in some detail. Evidence for expanding bubbles is seen with lines splitting into double components, often in areas of optical nebulosities, most prominently in the NGC 2024 H II region, where we argue that the bulk of the molecular gas is in the foreground of the H II region. High CO(32)/CO(10) line ratios reveal warm CO along the western edge of the Orion B cloud in the NGC 2023 & NGC 2024 region facing the IC 434 H II region. We see multiple, well separated radial velocity cloud components towards several fields and propose that L 1641-S consists of a sequence of clouds at increasingly larger distances. We find a small, seemingly spherical cloud, which we term Cow Nebula globule, north of NGC 2071. We confirm that we can trace high velocity line wings out to the extremely high velocity regime in protostellar molecular outflows for the NGC 2071-IR outflow and the NGC 2024 CO jet, and identify the protostellar dust core FIR4 (rather than FIR5) as the true driving source of the NGC 2024 monopolar outflow.

ISM: structure

ISM: jets and outflows

Submillimeter: ISM

ISM: kinematics and dynamics

ISM: clouds

ISM: bubbles


T. Stanke

European Southern Observatory (ESO)

Héctor G. Arce

Yale University

J. Bally

University of Colorado at Boulder

Per Bergman

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium, Observationssupport

J. Carpenter

Atacama Large Millimeter-submillimeter Array (ALMA)

C. J. Davis

National Science Foundation

W. R. F. Dent

Atacama Large Millimeter-submillimeter Array (ALMA)

J. Di Francesco

University of Victoria

National Research Council Canada

J. Eisloffel

Thüringer Landessternwarte Tautenburg

D. Froebrich

University Of Kent

A. Ginsburg

University of Florida

M. Heyer

University of Massachusetts

D. Johnstone

National Research Council Canada

University of Victoria

Diego Mardones

Universidad de Chile (UCH)

M. J. McCaughrean

European Space Research and Technology Centre (ESA ESTEC)

S. Thomas Megeath

University of Toledo

F. Nakamura

National Astronomical Observatory of Japan

M. D. Smith

University Of Kent

A. Stutz

Universidad de Concepción

Ken'ichi Tatematsu

National Astronomical Observatory of Japan

Christopher K. Walker

University of Arizona

J. P. Williams

University of Hawaii

H. Zinnecker

Universidad Autonoma de Chile

B. J. Swift

University of Arizona

Craig Kulesa

University of Arizona

B. Peters

University of Arizona

B. Duffy

University of Arizona

J. Kloosterman

University of Southern Indiana

U. A. Yildiz

Jet Propulsion Laboratory, California Institute of Technology

J. L. Pineda

Jet Propulsion Laboratory, California Institute of Technology

C. De Breuck

European Southern Observatory (ESO)

Th Klein

European Southern Observatory Santiago

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 658 A178


Meteorologi och atmosfärforskning

Astronomi, astrofysik och kosmologi

Ekonomisk geografi



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