The ALCHEMI Atlas: Principal Component Analysis Reveals Starburst Evolution in NGC 253
Journal article, 2024
Molecular lines are powerful diagnostics of the physical and chemical properties of the interstellar medium (ISM). These ISM properties, which affect future star formation, are expected to differ in starburst galaxies from those of more quiescent galaxies. We investigate the ISM properties in the central molecular zone of the nearby starburst galaxy NGC 253 using the ultrawide millimeter spectral scan survey from the Atacama Large Millimeter/submillimeter Array Large Program ALCHEMI. We present an atlas of velocity-integrated images at a 1.″6 resolution of 148 unblended transitions from 44 species, including the first extragalactic detection of HCNH+ and the first interferometric images of C3H+, NO, and HCS+. We conduct a principal component analysis (PCA) on these images to extract correlated chemical species and to identify key groups of diagnostic transitions. To the best of our knowledge, our data set is currently the largest astronomical set of molecular lines to which PCA has been applied. The PCA can categorize transitions coming from different physical components in NGC 253 such as (i) young starburst tracers characterized by high-excitation transitions of HC3N and complex organic molecules versus tracers of on-going star formation (radio recombination lines) and high-excitation transitions of CCH and CN tracing photodissociation regions, (ii) tracers of cloud-collision-induced shocks (low-excitation transitions of CH3OH, HNCO, HOCO+, and OCS) versus shocks from star formation-induced outflows (high-excitation transitions of SiO), as well as (iii) outflows showing emission from HOC+, CCH, H3O+, CO isotopologues, HCN, HCO+, CS, and CN. Our findings show these intensities vary with galactic dynamics, star formation activities, and stellar feedback.
Astrophysics - Astrophysics of Galaxies
Interstellar molecules
Interstellar medium
Astrochemistry
Starburst galaxies
Author
Nanase Harada
The Graduate University for Advanced Studies (SOKENDAI)
National Astronomical Observatory of Japan
Institute of Astronomy and Astrophysics, Academia Sinica
David S. Meier
National Radio Astronomy Observatory Socorro
New Mexico Institute of Mining and Technology
Sergio Martin
European Southern Observatory Santiago
Sebastien Muller
Chalmers, Space, Earth and Environment, Onsala Space Observatory
Kazushi Sakamoto
Institute of Astronomy and Astrophysics, Academia Sinica
Toshiki Saito
National Astronomical Observatory of Japan
Mark Gorski
Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University,
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Christian Henkel
Astronomy Department, Faculty of Science, King Abdulaziz University
Max-Planck Institute for Radio Astronomy
Kunihiko Tanaka
Department of Physics, Faculty of Science and Technology, Keio University
Jeffrey G. Mangum
National Radio Astronomy Observatory
Susanne Aalto
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Rebeca Aladro
Max-Planck Institute for Radio Astronomy
Mathilde Bouvier
Leiden Observatory, Leiden University
Laura Colzi
Centro de Astrobiologia (CAB)
Kimberly L. Emig
National Radio Astronomy Observatory
Ruben Herrero-Illana
Institute of Space Sciences (ICE) - CSIC
European Southern Observatory Santiago
Ko Yun Huang
Leiden Observatory, Leiden University
Kotaro Kohno
Institute of Astronomy, Graduate School of Science, The University of Tokyo
Sabine König
Chalmers, Space, Earth and Environment, Onsala Space Observatory
Kouichiro Nakanishi
National Astronomical Observatory of Japan
Yuri Nishimura
Institute of Astronomy, Graduate School of Science, The University of Tokyo
National Astronomical Observatory of Japan
S. Takano
Department of Physics, General Studies, College of Engineering, Nihon University
Victor M. Rivilla
Centro de Astrobiologia (CAB)
Serena Viti
Leiden Observatory, Leiden University
Yoshimasa Watanabe
Shibaura Institute of Technology
Paul van der Werf
Leiden Observatory, Leiden University
Yuki Yoshimura
Institute of Astronomy, Graduate School of Science, The University of Tokyo
Astrophysical Journal, Supplement Series
0067-0049 (ISSN) 1538-4365 (eISSN)
Vol. 271 2 38-88Subject Categories
Astronomy, Astrophysics and Cosmology
Infrastructure
Onsala Space Observatory
DOI
10.3847/1538-4365/ad1937