VALES – IV. Exploring the transition of star formation efficiencies between normal and starburst galaxies using APEX/SEPIA Band-5 and ALMA at low redshift
Hughes, T M
Muñoz Arancibia, A
Xu, C K
Willmer, C N A
Xue, Y Q
AffiliationUniv Arizona, Steward Observ
MetadataShow full item record
PublisherOXFORD UNIV PRESS
CitationC 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/stx3183
Rights© 2017 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
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AbstractIn 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.
VersionFinal published version
SponsorsChinese Academy of Sciences (CAS) through the CASSACA Postdoc Grant; CONICYT/ALMA funding Program in Astronomy/PCI Project ; FONDECYT ; 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 ; CONICYT (Chile) through FONDECYT postdoctoral research grant [3170942, 3160776]; NSFC ; National Key R&D Program of China [2017YFA0402704]; [NSFC-11643003]; [NSFC-11473026]; 
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