| Title: |
AlFoCS + F3D II: unexpectedly low gas-to-dust ratios in the Fornax galaxy cluster |
| Authors: |
Zabel, Nikki, Davis, Timothy A., Smith, Matthew W. L., Sarzi, Marc, Loni, Alessandro, Serra, Paolo, Lara-López, Maritza A., Cigan, Phil, Baes, Maarten, Bendo, George J., De Looze, Ilse, Iodice, Enrichetta, Kleiner, Dane, Koribalski, Bärbel S., Peletier, Reynier, Pinna, Francesca, de Zeeuw, P. Tim |
| Publication Year: |
2021 |
| Collection: |
Astrophysics |
| Subject Terms: |
Astrophysics - Astrophysics of Galaxies |
| More Details: |
We combine observations from ALMA, ATCA, MUSE, andHerschel to study gas-to-dust ratios in 15 Fornax cluster galaxies detected in the FIR/sub-mm by Herschel and observed by ALMA as part of the ALMA Fornax Cluster Survey (AlFoCS). The sample spans a stellar mass range of 8.3 $\leq$ log (M$_*$ / M$_\odot$) $\leq$ 11.16, and a variety of morphological types. We use gas-phase metallicities derived from MUSE observations (from the Fornax3D survey) to study these ratios as a function of metallicity, and to study dust-to-metal ratios, in a sub-sample of nine galaxies. We find that gas-to-dust ratios in Fornax galaxies are systematically lower than those in field galaxies at fixed stellar mass/metallicity. This implies that a relatively large fraction of the metals in these Fornax systems is locked up in dust, which is possibly due to altered chemical evolution as a result of the dense environment. The low ratios are not only driven by HI deficiencies, but H$_2$-to-dust ratios are also significantly decreased. This is different in the Virgo cluster, where low gas-to-dust ratios inside the virial radius are driven by low HI-to-dust ratios, while H$_2$-to-dust ratios are increased. Resolved observations of NGC1436 show a radial increase in H$_2$-to-dust ratio, and show that low ratios are present throughout the disc. We propose various explanations for the low H$_2$-to-dust ratios in the Fornax cluster, including the more efficient stripping of H$_2$ compared to dust, more efficient enrichment of dust in the star formation process, and altered ISM physics in the cluster environment.
Comment: Accepted for publication in MNRAS. 21 pages, 12 figures, and 3 tables |
| Document Type: |
Working Paper |
| DOI: |
10.1093/mnras/stab342 |
| Access URL: |
http://arxiv.org/abs/2102.02148 |
| Accession Number: |
edsarx.2102.02148 |
| Database: |
arXiv |
