Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample
International audience The origin of the high star formation rates (SFR) observed in high-redshift dusty star-forming galaxies is still unknown. Large fractions of dense molecular gas might provide part of the explanation, but there are few observational constraints on the amount of dense gas in hig...
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ftccsdartic:oai:HAL:hal-01914507v1 2023-05-15T18:23:23+02:00 Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample Béthermin, M. Greve, T.R. De Breuck, C. Vieira, J.D. Aravena, M. Chapman, S.C. Chen, Chian-Chou Dong, C. Hayward, C.C. Hezaveh, Y. Marrone, D.P. Narayanan, D. Phadke, K.A. Reuter, C.A. Spilker, J.S. Stark, A.A. Strandet, M.L. Weiß, A. Laboratoire d'Astrophysique de Marseille (LAM) Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales Toulouse (CNES) 2018 https://hal.archives-ouvertes.fr/hal-01914507 https://hal.archives-ouvertes.fr/hal-01914507/document https://hal.archives-ouvertes.fr/hal-01914507/file/aa33081-18.pdf https://doi.org/10.1051/0004-6361/201833081 en eng HAL CCSD EDP Sciences info:eu-repo/semantics/altIdentifier/arxiv/1810.04695 info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201833081 hal-01914507 https://hal.archives-ouvertes.fr/hal-01914507 https://hal.archives-ouvertes.fr/hal-01914507/document https://hal.archives-ouvertes.fr/hal-01914507/file/aa33081-18.pdf ARXIV: 1810.04695 doi:10.1051/0004-6361/201833081 INSPIRE: 1698058 info:eu-repo/semantics/OpenAccess ISSN: 0004-6361 EISSN: 1432-0756 Astronomy and Astrophysics - A&A https://hal.archives-ouvertes.fr/hal-01914507 Astronomy and Astrophysics - A&A, EDP Sciences, 2018, 620, pp.A115. ⟨10.1051/0004-6361/201833081⟩ submillimeter: galaxies galaxies: starburst galaxies: high-redshift galaxies: star formation galaxies: ISM [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] info:eu-repo/semantics/article Journal articles 2018 ftccsdartic https://doi.org/10.1051/0004-6361/201833081 2021-11-07T00:37:06Z International audience The origin of the high star formation rates (SFR) observed in high-redshift dusty star-forming galaxies is still unknown. Large fractions of dense molecular gas might provide part of the explanation, but there are few observational constraints on the amount of dense gas in high-redshift systems dominated by star formation. In this paper, we present the results of our Atacama large millimeter array (ALMA) program targeting dense-gas tracers (HCN(5-4), HCO+(5-4), and HNC(5-4)) in five strongly lensed galaxies from the South Pole Telescope (SPT) submillimeter galaxy sample. We detected two of these lines (S/N > 5) in SPT-125-47 at z = 2.51 and tentatively detected all three (S/N ∼ 3) in SPT0551-50 at z = 3.16. Since a significant fraction of our target lines is not detected, we developed a statistical method to derive unbiased mean properties of our sample taking into account both detections and non-detections. On average, the HCN(5-4) and HCO+(5-4) luminosities of our sources are a factor of ∼1.7 fainter than expected, based on the local L′HCN(5-4) − LIR relation, but this offset corresponds to only ∼2σ if we consider sample variance. We find that both the HCO+/HCN and HNC/HCN flux ratios are compatible with unity. The first ratio is expected for photo-dominated regions (PDRs) while the second is consistent with PDRs or X-ray dominated regions (XDRs) and/or mid-infrared (IR) pumping of HNC. Our sources are at the high end of the local relation between the star formation efficiency, determined using the LIR/[CI] and LIR/CO ratios, and the dense-gas fraction, estimated using the HCN/[CI] and HCN/CO ratios. Finally, in SPT0125-47, which has the highest signal-to-noise ratio, we found that the velocity profiles of the lines tracing dense (HCN, HCO+) and lower-density (CO, [CI]) molecular gas are similar. In addition to these lines, we obtained one robust and one tentative detection of 13CO(4-3) and found an average I12CO(4-3)/I13CO(4-3) flux ratio of 26.1−3.5+4.5, indicating a young but not ... Article in Journal/Newspaper South pole Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) South Pole Astronomy & Astrophysics 620 A115 |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
submillimeter: galaxies galaxies: starburst galaxies: high-redshift galaxies: star formation galaxies: ISM [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] |
spellingShingle |
submillimeter: galaxies galaxies: starburst galaxies: high-redshift galaxies: star formation galaxies: ISM [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] Béthermin, M. Greve, T.R. De Breuck, C. Vieira, J.D. Aravena, M. Chapman, S.C. Chen, Chian-Chou Dong, C. Hayward, C.C. Hezaveh, Y. Marrone, D.P. Narayanan, D. Phadke, K.A. Reuter, C.A. Spilker, J.S. Stark, A.A. Strandet, M.L. Weiß, A. Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample |
topic_facet |
submillimeter: galaxies galaxies: starburst galaxies: high-redshift galaxies: star formation galaxies: ISM [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] |
description |
International audience The origin of the high star formation rates (SFR) observed in high-redshift dusty star-forming galaxies is still unknown. Large fractions of dense molecular gas might provide part of the explanation, but there are few observational constraints on the amount of dense gas in high-redshift systems dominated by star formation. In this paper, we present the results of our Atacama large millimeter array (ALMA) program targeting dense-gas tracers (HCN(5-4), HCO+(5-4), and HNC(5-4)) in five strongly lensed galaxies from the South Pole Telescope (SPT) submillimeter galaxy sample. We detected two of these lines (S/N > 5) in SPT-125-47 at z = 2.51 and tentatively detected all three (S/N ∼ 3) in SPT0551-50 at z = 3.16. Since a significant fraction of our target lines is not detected, we developed a statistical method to derive unbiased mean properties of our sample taking into account both detections and non-detections. On average, the HCN(5-4) and HCO+(5-4) luminosities of our sources are a factor of ∼1.7 fainter than expected, based on the local L′HCN(5-4) − LIR relation, but this offset corresponds to only ∼2σ if we consider sample variance. We find that both the HCO+/HCN and HNC/HCN flux ratios are compatible with unity. The first ratio is expected for photo-dominated regions (PDRs) while the second is consistent with PDRs or X-ray dominated regions (XDRs) and/or mid-infrared (IR) pumping of HNC. Our sources are at the high end of the local relation between the star formation efficiency, determined using the LIR/[CI] and LIR/CO ratios, and the dense-gas fraction, estimated using the HCN/[CI] and HCN/CO ratios. Finally, in SPT0125-47, which has the highest signal-to-noise ratio, we found that the velocity profiles of the lines tracing dense (HCN, HCO+) and lower-density (CO, [CI]) molecular gas are similar. In addition to these lines, we obtained one robust and one tentative detection of 13CO(4-3) and found an average I12CO(4-3)/I13CO(4-3) flux ratio of 26.1−3.5+4.5, indicating a young but not ... |
author2 |
Laboratoire d'Astrophysique de Marseille (LAM) Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales Toulouse (CNES) |
format |
Article in Journal/Newspaper |
author |
Béthermin, M. Greve, T.R. De Breuck, C. Vieira, J.D. Aravena, M. Chapman, S.C. Chen, Chian-Chou Dong, C. Hayward, C.C. Hezaveh, Y. Marrone, D.P. Narayanan, D. Phadke, K.A. Reuter, C.A. Spilker, J.S. Stark, A.A. Strandet, M.L. Weiß, A. |
author_facet |
Béthermin, M. Greve, T.R. De Breuck, C. Vieira, J.D. Aravena, M. Chapman, S.C. Chen, Chian-Chou Dong, C. Hayward, C.C. Hezaveh, Y. Marrone, D.P. Narayanan, D. Phadke, K.A. Reuter, C.A. Spilker, J.S. Stark, A.A. Strandet, M.L. Weiß, A. |
author_sort |
Béthermin, M. |
title |
Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample |
title_short |
Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample |
title_full |
Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample |
title_fullStr |
Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample |
title_full_unstemmed |
Dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the SPT SMG sample |
title_sort |
dense-gas tracers and carbon isotopes in five 2.5 < z < 4 lensed dusty star-forming galaxies from the spt smg sample |
publisher |
HAL CCSD |
publishDate |
2018 |
url |
https://hal.archives-ouvertes.fr/hal-01914507 https://hal.archives-ouvertes.fr/hal-01914507/document https://hal.archives-ouvertes.fr/hal-01914507/file/aa33081-18.pdf https://doi.org/10.1051/0004-6361/201833081 |
geographic |
South Pole |
geographic_facet |
South Pole |
genre |
South pole |
genre_facet |
South pole |
op_source |
ISSN: 0004-6361 EISSN: 1432-0756 Astronomy and Astrophysics - A&A https://hal.archives-ouvertes.fr/hal-01914507 Astronomy and Astrophysics - A&A, EDP Sciences, 2018, 620, pp.A115. ⟨10.1051/0004-6361/201833081⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/arxiv/1810.04695 info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201833081 hal-01914507 https://hal.archives-ouvertes.fr/hal-01914507 https://hal.archives-ouvertes.fr/hal-01914507/document https://hal.archives-ouvertes.fr/hal-01914507/file/aa33081-18.pdf ARXIV: 1810.04695 doi:10.1051/0004-6361/201833081 INSPIRE: 1698058 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1051/0004-6361/201833081 |
container_title |
Astronomy & Astrophysics |
container_volume |
620 |
container_start_page |
A115 |
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1766202965395243008 |