VALES – IV. Exploring the transition of star formation efficiencies between normal and starburst galaxies using APEX/SEPIA Band-5 and ALMA at low redshift
Publisher
OXFORD UNIV PRESSCitation
C Cheng, E Ibar, T M Hughes, V Villanueva, R Leiton, G Orellana, A Muñoz Arancibia, N Lu, C K Xu, C N A Willmer, J Huang, T Cao, C Yang, Y Q Xue, K Torstensson; VALES – IV. Exploring the transition of star formation efficiencies between normal and starburst galaxies using APEX/SEPIA Band-5 and ALMA at low redshift, Monthly Notices of the Royal Astronomical Society, Volume 475, Issue 1, 21 March 2018, Pages 248–256, https://doi.org/10.1093/mnras/stx3183Rights
© 2017 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
In this work, we present new the Swedish-ESO PI receiver for the Atacama Pathfinder Experiment APEX/SEPIA Band-5 observations targeting the CO (J = 2-1) emission line of 24 Herschel-detected galaxies at z = 0.1-0.2. Combining this sample with our recent new Valparafso ALMA Line Emission Survey (VALES), we investigate the star formation efficiencies [SFEs = star formation rate (SFR)/M-H2] of galaxies at low redshift. We find the SFE of our sample bridges the gap between normal star-forming galaxies and Ultra-Luminous Infrared Galaxies (ULIRGs), which are thought to be triggered by different star formation modes. Considering the SFE' as the SFR and the L'(CO) ratio, our data show a continuous and smooth increment as a function of infrared luminosity (or star formation rate) with a scatter about 0.5 dex, instead of a steep jump with a bimodal behaviour. This result is due to the use of a sample with a much larger range of sSFR/sSFR(ms) using LIRGs, with luminosities covering the range between normal and ULIRGs. We conclude that the main parameters controlling the scatter of the SFE in star-forming galaxies are the systematic uncertainty of the alpha(CO) conversion factor, the gas fraction, and physical size.ISSN
0035-87111365-2966
Version
Final published versionSponsors
Chinese Academy of Sciences (CAS) through the CASSACA Postdoc Grant; CONICYT/ALMA funding Program in Astronomy/PCI Project [31140020]; FONDECYT [1171710]; Chinese Academy of Sciences (CAS); National Commission for Scientific and Technological Research of Chile (CONICYT) through a CAS-CONICYT Joint Postdoctoral Fellowship; Comite Mixto ESO-GOBIERNO DE CHILE; GEMINI-CONICYT FUND [32130024]; CONICYT (Chile) through FONDECYT postdoctoral research grant [3170942, 3160776]; NSFC [11673028]; National Key R&D Program of China [2017YFA0402704]; [NSFC-11643003]; [NSFC-11473026]; [11421303]Additional Links
https://academic.oup.com/mnras/article/475/1/248/4712246Scopus Count
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