Stellar and AGN Feedback Probed with Outflows in JWST Galaxies at z=3-9: Implications of Frequent Nearly-Spherical Galactic Fountains
Abstract
We study outflows in 130 galaxies with -22<MUV<-16 at z=3-9 identified in JWST NIRSpec and NIRCam WFSS data taken by the ERO, CEERS, FRESCO, GLASS, and JADES programs. We identify 30 out of the 130 galaxies with broad components of FWHM~200-700 km/s in the emission lines of H${\alpha}$ and [OIII] that trace ionized outflows, and find no excesses from the star-formation main sequence. Four out of the 30 outflowing galaxies are Type 1 AGN whose H${\alpha}$ emission lines include line profile components as broad as FWHM>1000 km/s. With the velocity shift and line widths of the outflow broad lines, we obtain ~80-500 km/s for the outflow velocities. We find that the outflow velocities as a function of star-formation rate are comparable to or higher than those of galaxies at z~1, accounting for the selection bias, while the outflow velocities of AGN are large but not significantly different from the others. Interestingly, these outflow velocities are typically not high enough to escape from the galactic potentials, suggestive of fountain-type outflows, which are concluded on the basis of thorough comparisons with recent JWST results. We estimate mass loading factors ${\eta}$ to be 0.1-1 that are not particularly large, but comparable with those of z~1 outflows. The large fraction of galaxies with outflows (30% with high resolution data) provides constraints on outflow parameters, suggesting a wide opening angle of >45 deg and a large duty-cycle of >30%, which gives a picture of more frequent and spherical outflows in high-z galaxies.
- Publication:
-
arXiv e-prints
- Pub Date:
- October 2023
- DOI:
- 10.48550/arXiv.2310.06614
- arXiv:
- arXiv:2310.06614
- Bibcode:
- 2023arXiv231006614X
- Keywords:
-
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 16 pages, 11 figures, submitted to the Astrophysical Journal