| Autor: |
Sweet, Sarah M, Fisher, Deanne B, Savorgnan, Giulia, Glazebrook, Karl, Obreschkow, Danail, Gillman, Steven, Tiley, Alfred L, Lagos, Claudia D P, Wang, Liang, Swinbank, A Mark, Bower, Richard, Sharples, Ray M |
| Předmět: |
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| Zdroj: |
Monthly Notices of the Royal Astronomical Society; Jun2019, Vol. 485 Issue 4, p5700-5714, 15p |
| Abstrakt: |
We present stellar specific angular momentum j * measurements of two z ∼ 1.5 galaxies in the KGES sample and 12 DYNAMO z ∼ 0.1 analogues of high-redshift galaxies. We combine natural seeing integral field spectroscopic data to trace line emission out to high multiples of effective radius r e, with adaptive optics assisted Keck/OSIRIS observations to trace the rapid rise in rotation curve in the inner regions. Our spaxel-wise integration method gives results that are on average within measurement uncertainty of the traditional rotation curve model method. At z ∼ 0, combining GMOS and OSIRIS data sets improves the measurement uncertainty in j * from 13 per cent (GMOS only) or 16 per cent (OSIRIS only) to 10 per cent. At z ∼ 1.5, systematics allow for at best 20 per cent uncertainty on j *. DYNAMO analogues of high- z galaxies have low j * for their stellar mass M *, and low bulge-to-total light ratio β for their j */ M *. The high- z galaxy COSMOS 127977 has j */ M * consistent with normal local disc galaxies, while UDS 78317 is consistent with local analogues. However, our high-resolution OSIRIS data reveal that UDS 78317 may be a merging system. We report a relationship between distance to the β− j */ M * plane and the ratio of velocity dispersion to rotational velocity σ/ v max, where galaxies that deviate more from the plane are more dispersion-dominated due to turbulence. Much of the scatter in M *− j * that is not explained by variations in the bulge-to-total ratio or evolution with redshift may be driven by increased turbulence due to star formation, or by treating mergers as rotating discs. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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