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Title: Extreme CO Isotopic Abundances in the ULIRG IRAS 13120-5453: An Extremely Young Starburst or Top-heavy Initial Mass Function

Abstract

We present ALMA {sup 12}CO (J = 1-0, 3-2 and 6-5), {sup 13}CO (J = 1-0), and C{sup 18}O (J = 1-0) observations of the local ultraluminous infrared galaxy (ULIRG) IRAS 13120-5453. The morphologies of the three isotopic species differ, as {sup 13}CO shows a hole in emission toward the center. We measure integrated brightness temperature line ratios of {sup 12}CO/{sup 13}CO ≥ 60 (exceeding 200) and {sup 13}CO/C{sup 18}O ≤ 1 in the central region. Assuming optical thin emission, C{sup 18}O is more abundant than {sup 13}CO in several regions. The abundances within the central 500 pc are consistent with the enrichment of the interstellar medium via a young starburst (<7 Myr), a top-heavy initial mass function, or a combination of both.

Authors:
 [1];  [2];  [3];  [4]
  1. MPI for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany)
  2. Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada)
  3. Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, SE-439 94 Onsala (Sweden)
  4. Instituto de Astrofśica, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile)
Publication Date:
OSTI Identifier:
22654483
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 840; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; CARBON; CARBON 12; CARBON 13; CARBON 18; CARBON MONOXIDE; EMISSION; GALAXIES; INTERACTIONS; ISOTOPES; MASS; RADIANT HEAT TRANSFER

Citation Formats

Sliwa, Kazimierz, Wilson, Christine D., Aalto, Susanne, and Privon, George C., E-mail: sliwa@mpia-hd.mpg.de. Extreme CO Isotopic Abundances in the ULIRG IRAS 13120-5453: An Extremely Young Starburst or Top-heavy Initial Mass Function. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA6EA4.
Sliwa, Kazimierz, Wilson, Christine D., Aalto, Susanne, & Privon, George C., E-mail: sliwa@mpia-hd.mpg.de. Extreme CO Isotopic Abundances in the ULIRG IRAS 13120-5453: An Extremely Young Starburst or Top-heavy Initial Mass Function. United States. doi:10.3847/2041-8213/AA6EA4.
Sliwa, Kazimierz, Wilson, Christine D., Aalto, Susanne, and Privon, George C., E-mail: sliwa@mpia-hd.mpg.de. Wed . "Extreme CO Isotopic Abundances in the ULIRG IRAS 13120-5453: An Extremely Young Starburst or Top-heavy Initial Mass Function". United States. doi:10.3847/2041-8213/AA6EA4.
@article{osti_22654483,
title = {Extreme CO Isotopic Abundances in the ULIRG IRAS 13120-5453: An Extremely Young Starburst or Top-heavy Initial Mass Function},
author = {Sliwa, Kazimierz and Wilson, Christine D. and Aalto, Susanne and Privon, George C., E-mail: sliwa@mpia-hd.mpg.de},
abstractNote = {We present ALMA {sup 12}CO (J = 1-0, 3-2 and 6-5), {sup 13}CO (J = 1-0), and C{sup 18}O (J = 1-0) observations of the local ultraluminous infrared galaxy (ULIRG) IRAS 13120-5453. The morphologies of the three isotopic species differ, as {sup 13}CO shows a hole in emission toward the center. We measure integrated brightness temperature line ratios of {sup 12}CO/{sup 13}CO ≥ 60 (exceeding 200) and {sup 13}CO/C{sup 18}O ≤ 1 in the central region. Assuming optical thin emission, C{sup 18}O is more abundant than {sup 13}CO in several regions. The abundances within the central 500 pc are consistent with the enrichment of the interstellar medium via a young starburst (<7 Myr), a top-heavy initial mass function, or a combination of both.},
doi = {10.3847/2041-8213/AA6EA4},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 840,
place = {United States},
year = {Wed May 10 00:00:00 EDT 2017},
month = {Wed May 10 00:00:00 EDT 2017}
}
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