The 4MOST–Gaia Purely Astrometric Quasar Survey (4G-PAQS)

Krogager, J. -K.; Leighly, K. M.; Fynbo, J. P. U.; Heintz, K. E.; Balashev, S.; Bauer, F. E.; Berg, T.; Choi, H.; Christensen, L. B.; De Cia, A.; Ellison, S.; Geier, S.; Glikman, E.; Gupta, N.; Konstantopoulou, C.; Kosenko, D.; Ledoux, C.; López, S.; Milvang-Jensen, B.; Morabito, L.; Møller, P.; Noterdaeme, P.; Pettini, M.; Prochaska, J. X.; Raimundo, S.; Richard, J.; Srianand, R.; Telikova, K.; Terndrup, D.; Tripp, T. M.; Vestergaard, M.; Zafar, T.
Bibliographical reference

The Messenger

Advertised on:
3
2023
Number of authors
32
IAC number of authors
1
Citations
3
Refereed citations
2
Description
The 4MOST–Gaia Purely Astrometric Quasar Survey (4G-PAQS) will carry out the first large-scale, colour-independent quasar survey selected solely on the basis of astrometry from Gaia. Our main objective is to quantify the selection effects of current colour-selected samples. These colour-selected samples bias our view of the neutral gas and its chemical enrichment because of dust obscuration and reddening of optical colours. Moreover, the broad absorption-line outflows observed in quasars are under-represented by optical colour selection. 4G-PAQS will provide the first sample to overcome these challenges and will constrain the physical and chemical properties of gas in galaxies and quasars at cosmic noon.