Galactic Star Formation with NIKA2 (GASTON): Evidence of mass accretion onto dense clumps

¹ School of Physics and Astronomy, Cardiff University, Queen’s Buildings, The Parade, Cardiff, CF24 3AA, UK
² LLR (Laboratoire Leprince-Ringuet), CNRS, École Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
³ AIM, CEA, CNRS, Université Paris-Saclay, Université Paris Diderot, Sorbonne Paris Cité, 91191 Gifsur-Yvette, France
⁴ Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
⁵ Univ. Grenoble Alpes, CNRS, Grenoble INP, LPSC-IN2P3, 53, avenue des Martyrs, 38000 Grenoble, France
⁶ Institut d’Astrophysique Spatiale (IAS), CNRS, Université Paris Sud, Orsay, France
⁷ Institut Néel, CNRS, Université Grenoble Alpes, France
⁸ Institut de RadioAstronomie Millimétrique (IRAM), Grenoble, France
⁹ Aix Marseille Univ, CNRS, CNES, LAM (Laboratoire d’Astrophysique de Marseille), Marseille, France
¹⁰ Rudjer Boškovic Institute, Bijenicka cesta 54, 10000 Zagreb, Croatia
¹¹ Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
¹² Chinese Academy of Sciences South America Center for Astronomy, National Astronomical Observatories, CAS, Beijing 100101, PR China
¹³ Instituto de Astronomía, Universidad Católica del Norte, Av. Angamos 0610, Antofagasta 1270709, Chile
¹⁴ Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, 28850 Madrid, Spain
¹⁵ Instituto de Radioastronomía Milimétrica (IRAM), Granada, Spain
¹⁶ LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC, 75014 Paris, France
¹⁷ School of Earth and Space Exploration and Department of Physics, Arizona State University, Tempe, AZ 85287, USA
¹⁸ Univ. Toulouse, CNRS, IRAP, 9 Av. du Colonel Roche, BP 44346, 31028, Toulouse, France
¹⁹ Laboratoire de Physique de l’École Normale Supérieure, ENS, PSL Research University, CNRS, Sorbonne Université, Université de Paris, 75005 Paris, France
²⁰ Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA, 19104, USA
²¹ Institut d’Astrophysique de Paris, Sarbonne Université, CNRS (UMR7095), 75014 Paris, France
²² Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
²³ Caltech, Pasadena, CA 91125, USA
²⁴ Astronomisches Rechen-Institut, Zentrum für Astronomie der Universit at Heidelberg, Monchhofstraße 12-14, D-69120 Heidelberg, Germany

^* e-mail: RigbyA@cardiff.ac.uk

Published online: 17 January 2022

Abstract

High-mass stars (m_* ≳ 8 M_⊙) play a crucial role in the evolution of galaxies, and so it is imperative that we understand how they are formed. We have used the New IRAM KIDs Array 2 (NIKA2) camera on the Institut de Radio Astronomie Millimétrique (IRAM) 30-m telescope to conduct high-sensitivity continuum mapping of ~ 2 deg² of the Galactic plane (GP) as part of the Galactic Star Formation with NIKA2 (GASTON) large program. We have identified a total of 1467 clumps within our deep 1.15 mm continuum maps and, by using overlapping continuum, molecular line, and maser parallax data, we have determined their distances and physical properties. By placing them upon an approximate evolutionary sequence based upon 8 μm Spitzer imaging, we find evidence that the most massive dense clumps accrete material from their surrounding environment during their early evolution, before dispersing as star formation advances, supporting clump-fed models of high-mass star formation.