Bibliographic Details
| Title: |
The Nature of 500 Micron Risers II: Sub-mm Faint Dusty Star Forming Galaxies |
| Authors: |
Cairns, J., Clements, D. L., Greenslade, J., Petitpas, G., Cheng, T., Ding, Y., Parmar, A., Pérez-Fournon, I., Riechers, D. |
| Publication Year: |
2022 |
| Collection: |
Astrophysics |
| Subject Terms: |
Astrophysics - Astrophysics of Galaxies |
| More Details: |
We present SCUBA-2 and SMA follow-up observations of four candidate high redshift Dusty Star-Forming Galaxies, selected as sources with rising SEDs in the 250, 350 and 500$\mu$m Herschel SPIRE bands. Previous SMA observations showed no counterparts to these sources, but in our deeper sub-mm observations we detect counterparts to all four 500$\mu$m risers, with three resolving into multiple systems. For these three multiple systems, the SMA 345GHz ($\approx 870\mu$m) observations recover $123 \pm 73\%$, $60 \pm 15\%$ and $19 \pm 4\%$ respectively of the integrated 850$\mu$m flux density from SCUBA-2, indicating that there may be additional sources below our SMA detection limit making up a dense, protocluster core. The fourth 500$\mu$m riser was observed at a lower frequency and so we cannot make a similar comparison. We estimate photometric redshifts based on FIR/sub-mm colours, finding that 3/4 likely lie at $z \geq 2$. This fits with the interpretation that the 500$\mu$m riser selection criterion selects both intrinsically red, individual galaxies at $z > 4$, and multiple systems at more moderate redshifts, artificially reddened by the effects of blending. We use the SCUBA-2 850$\mu$m maps to investigate the environments of these 500$\mu$m risers. By constructing cumulative number counts and estimating photometric redshifts for surrounding SCUBA-2 detections, we find that one of our 500$\mu$m risers could plausibly reside in a $z \geq 2$ protocluster. We infer that bright 500$\mu$m risers with faint 850$\mu$m flux densities are typically multiple systems at $z \geq 2$ that may reside in overdensities of bright sub-mm galaxies.
Comment: 20 pages, 13 figures, 3 tables. Submitted to MNRAS |
| Document Type: |
Working Paper |
| Access URL: |
http://arxiv.org/abs/2203.01049 |
| Accession Number: |
edsarx.2203.01049 |
| Database: |
arXiv |
