Star-forming Main Sequence of Giant Low Surface Brightness Galaxies
Giant low surface brightness galaxies (GLSBGs) are fundamentally distinct from normal galaxies and other types of LSBGs in terms of star formation and evolution. In this work, we collected 27 local GLSBGs from the literature. They have high stellar masses ( M _* > 10 ^10 M _⊙ ) and low far-ultrav...
| Main Authors: | , , , , |
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| Format: | Article |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal |
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| Online Access: | https://doi.org/10.3847/1538-4357/ad05bd |
| _version_ | 1827586686747410432 |
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| author | Wei Du Cheng Cheng Pengliang Du Lin Du Hong Wu |
| author_facet | Wei Du Cheng Cheng Pengliang Du Lin Du Hong Wu |
| author_sort | Wei Du |
| collection | DOAJ |
| description | Giant low surface brightness galaxies (GLSBGs) are fundamentally distinct from normal galaxies and other types of LSBGs in terms of star formation and evolution. In this work, we collected 27 local GLSBGs from the literature. They have high stellar masses ( M _* > 10 ^10 M _⊙ ) and low far-ultraviolet-based star formation rates (SFRs). With specific star formation rates (sSFRs) lower than the characteristic value of local star-forming galaxies (SFGs) of M _* = 10 ^10 M _⊙ (sSFR < 0.1 Gyr ^−1 ), GLSBGs deviate from the star formation main sequence (MS) defined for local SFGs respectively by Elbaz et al. (E07) and Saintonge et al. (S16) at the high- M _* regime. They are H i -rich systems with H i gas mass fractions ( f _H I ) higher than the S16 MS galaxies, but have little molecular gas (H _2 ), implying a quite low efficiency of H i -to-H _2 transition due to low H i surface densities (Σ H i ) that are far lower than the minimum Σ H i of 6–8 M _⊙ pc ^−2 required for shielding the formed H _2 from photodissociation. For GLSBGs, the inner, bulge-dominated parts with lower SFRs and higher M _* are the main force pulling the entire GLSBG sample off of the MS, while the outer, disk-dominated parts with relatively higher SFRs and lower M _* reduce the deviation from the MS. For some cases, the outer, disk-dominated parts even tend to follow the MS. In the aspect of near-ultraviolet − r versus g − r colors, the outer, disk-dominated parts are blue and behave similarly to normal SFGs while the inner, bulge-dominated parts are statistically redder, indicating an inside–out star formation mechanism for GLSBGs. They show few signs of external interactions in morphology, excluding the recent major merger scenario. |
| first_indexed | 2024-03-09T00:05:24Z |
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| language | English |
| last_indexed | 2024-03-09T00:05:24Z |
| publishDate | 2023-01-01 |
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| series | The Astrophysical Journal |
| spelling | doaj.art-ab9948222bce440092adac07e5c7a0622023-12-12T13:26:28ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-01959210510.3847/1538-4357/ad05bdStar-forming Main Sequence of Giant Low Surface Brightness GalaxiesWei Du0https://orcid.org/0000-0003-4546-8216Cheng Cheng1https://orcid.org/0000-0003-0202-0534Pengliang Du2Lin Du3Hong Wu4Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences , Beijing 100101, People’s Republic of ChinaKey Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences , Beijing 100101, People’s Republic of China; Chinese Academy of Sciences , South America Center for Astronomy, National Astronomical Observatories, Beijing 100101, People’s Republic of ChinaKey Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences , Beijing 100101, People’s Republic of China; School of Astronomy and Space Science, University of Chinese Academy of Sciences , 19A Yuquan Road, Shijingshan District, Beijing 100049, People’s Republic of ChinaKey Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences , Beijing 100101, People’s Republic of China; School of Astronomy and Space Science, University of Chinese Academy of Sciences , 19A Yuquan Road, Shijingshan District, Beijing 100049, People’s Republic of ChinaKey Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences , Beijing 100101, People’s Republic of ChinaGiant low surface brightness galaxies (GLSBGs) are fundamentally distinct from normal galaxies and other types of LSBGs in terms of star formation and evolution. In this work, we collected 27 local GLSBGs from the literature. They have high stellar masses ( M _* > 10 ^10 M _⊙ ) and low far-ultraviolet-based star formation rates (SFRs). With specific star formation rates (sSFRs) lower than the characteristic value of local star-forming galaxies (SFGs) of M _* = 10 ^10 M _⊙ (sSFR < 0.1 Gyr ^−1 ), GLSBGs deviate from the star formation main sequence (MS) defined for local SFGs respectively by Elbaz et al. (E07) and Saintonge et al. (S16) at the high- M _* regime. They are H i -rich systems with H i gas mass fractions ( f _H I ) higher than the S16 MS galaxies, but have little molecular gas (H _2 ), implying a quite low efficiency of H i -to-H _2 transition due to low H i surface densities (Σ H i ) that are far lower than the minimum Σ H i of 6–8 M _⊙ pc ^−2 required for shielding the formed H _2 from photodissociation. For GLSBGs, the inner, bulge-dominated parts with lower SFRs and higher M _* are the main force pulling the entire GLSBG sample off of the MS, while the outer, disk-dominated parts with relatively higher SFRs and lower M _* reduce the deviation from the MS. For some cases, the outer, disk-dominated parts even tend to follow the MS. In the aspect of near-ultraviolet − r versus g − r colors, the outer, disk-dominated parts are blue and behave similarly to normal SFGs while the inner, bulge-dominated parts are statistically redder, indicating an inside–out star formation mechanism for GLSBGs. They show few signs of external interactions in morphology, excluding the recent major merger scenario.https://doi.org/10.3847/1538-4357/ad05bdLow surface brightness galaxiesGiant galaxiesStar formationScaling relations |
| spellingShingle | Wei Du Cheng Cheng Pengliang Du Lin Du Hong Wu Star-forming Main Sequence of Giant Low Surface Brightness Galaxies The Astrophysical Journal Low surface brightness galaxies Giant galaxies Star formation Scaling relations |
| title | Star-forming Main Sequence of Giant Low Surface Brightness Galaxies |
| title_full | Star-forming Main Sequence of Giant Low Surface Brightness Galaxies |
| title_fullStr | Star-forming Main Sequence of Giant Low Surface Brightness Galaxies |
| title_full_unstemmed | Star-forming Main Sequence of Giant Low Surface Brightness Galaxies |
| title_short | Star-forming Main Sequence of Giant Low Surface Brightness Galaxies |
| title_sort | star forming main sequence of giant low surface brightness galaxies |
| topic | Low surface brightness galaxies Giant galaxies Star formation Scaling relations |
| url | https://doi.org/10.3847/1538-4357/ad05bd |
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