Saved in:
| Main Authors: | , , , , , , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2503.21230 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866913762207858688 |
|---|---|
| author | Shim, Hyunjin Baek, Junhyun Kim, Dohyeong Kim, Minjin Song, Hyunmi Lim, Gu Cho, Jaejun Jeong, Hayeong Jeong, Yejin Kang, Ye-Eun Lee, Dongseob Park, Junyeong Seo, Eunsuk Song, Junho Yeo, Been |
| author_facet | Shim, Hyunjin Baek, Junhyun Kim, Dohyeong Kim, Minjin Song, Hyunmi Lim, Gu Cho, Jaejun Jeong, Hayeong Jeong, Yejin Kang, Ye-Eun Lee, Dongseob Park, Junyeong Seo, Eunsuk Song, Junho Yeo, Been |
| contents | We present CO(1-0) observations of 50 star-forming galaxies at 0.01<z<0.35, for which 3.3$\,μ$m PAH emission flux or its upper limit is available. A scaling relation between 3.3$\,μ$m PAH luminosity and CO(1-0) luminosity is established covering ~2 orders of magnitude in total IR luminosity and CO luminosity, with a scatter of ~0.23 dex: $\mathrm{log}\,L_\mathrm{3.3}/\mathrm{L}_\odot=(1.00\pm0.07)\times\mathrm{log}\,L_\mathrm{CO(1-0)}^\prime/(\mathrm{K\,km\,s^{-1}\,pc^2})+(-1.10\pm0.70)$. The slope is near unity, allowing the use of a single value of $\langle\mathrm{log}\,(L_\mathrm{3.3}/L_\mathrm{CO(1-0)}^\prime)\rangle=-1.09\pm0.36~[\mathrm{L}_\odot/(\mathrm{K\,km\,s^{-1}\,pc^2})]$ in the conversion between 3.3$\,μ$m PAH and CO luminosities. The variation in the $L_\mathrm{3.3}/L_\mathrm{CO}^\prime$ ratio is not dependent on the galaxy properties, including total IR luminosity, stellar mass, and SFR excess. The total gas mass, estimated using dust-to-gas ratio and dust mass, is correlated with 3.3$\,μ$m PAH luminosity, in line with the prescription using $α_\mathrm{CO}=0.8-4.5$ covering both normal star-forming galaxies and starburst galaxies. AGN-dominated galaxies tend to have a lower $L_\mathrm{3.3}/L_\mathrm{CO}^\prime$ than non-AGN galaxies, which needs to be investigated further with an increased sample size. The established $L_\mathrm{3.3}$-$L_\mathrm{CO}^\prime$ correlation is expected to be applicable to wide-field near-infrared spectrophotometric surveys that allow the detection of 3.3$\,μ$m emission from numerous low-redshift galaxies. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2503_21230 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Possibility of using 3.3$μ$m PAH luminosity as a molecular gas mass estimator Shim, Hyunjin Baek, Junhyun Kim, Dohyeong Kim, Minjin Song, Hyunmi Lim, Gu Cho, Jaejun Jeong, Hayeong Jeong, Yejin Kang, Ye-Eun Lee, Dongseob Park, Junyeong Seo, Eunsuk Song, Junho Yeo, Been Astrophysics of Galaxies We present CO(1-0) observations of 50 star-forming galaxies at 0.01<z<0.35, for which 3.3$\,μ$m PAH emission flux or its upper limit is available. A scaling relation between 3.3$\,μ$m PAH luminosity and CO(1-0) luminosity is established covering ~2 orders of magnitude in total IR luminosity and CO luminosity, with a scatter of ~0.23 dex: $\mathrm{log}\,L_\mathrm{3.3}/\mathrm{L}_\odot=(1.00\pm0.07)\times\mathrm{log}\,L_\mathrm{CO(1-0)}^\prime/(\mathrm{K\,km\,s^{-1}\,pc^2})+(-1.10\pm0.70)$. The slope is near unity, allowing the use of a single value of $\langle\mathrm{log}\,(L_\mathrm{3.3}/L_\mathrm{CO(1-0)}^\prime)\rangle=-1.09\pm0.36~[\mathrm{L}_\odot/(\mathrm{K\,km\,s^{-1}\,pc^2})]$ in the conversion between 3.3$\,μ$m PAH and CO luminosities. The variation in the $L_\mathrm{3.3}/L_\mathrm{CO}^\prime$ ratio is not dependent on the galaxy properties, including total IR luminosity, stellar mass, and SFR excess. The total gas mass, estimated using dust-to-gas ratio and dust mass, is correlated with 3.3$\,μ$m PAH luminosity, in line with the prescription using $α_\mathrm{CO}=0.8-4.5$ covering both normal star-forming galaxies and starburst galaxies. AGN-dominated galaxies tend to have a lower $L_\mathrm{3.3}/L_\mathrm{CO}^\prime$ than non-AGN galaxies, which needs to be investigated further with an increased sample size. The established $L_\mathrm{3.3}$-$L_\mathrm{CO}^\prime$ correlation is expected to be applicable to wide-field near-infrared spectrophotometric surveys that allow the detection of 3.3$\,μ$m emission from numerous low-redshift galaxies. |
| title | Possibility of using 3.3$μ$m PAH luminosity as a molecular gas mass estimator |
| topic | Astrophysics of Galaxies |
| url | https://arxiv.org/abs/2503.21230 |