Spatially Resolved Circumgalactic Medium around a Star-Forming Galaxy Driving a Galactic Outflow at $z\approx 0.8$
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866908410088259584 |
|---|---|
| author | Shaban, Ahmed Bordoloi, Rongmon O'Meara, John M. Sharon, Keren Tejos, Nicolas Lopez, Sebastian Ledoux, Cédric Barrientos, L. Felipe Rigby, Jane R. |
| author_facet | Shaban, Ahmed Bordoloi, Rongmon O'Meara, John M. Sharon, Keren Tejos, Nicolas Lopez, Sebastian Ledoux, Cédric Barrientos, L. Felipe Rigby, Jane R. |
| contents | We report the small-scale spatial variation in cool ($T\sim 10^4 K$) Mg II absorption detected in the circumgalactic medium (CGM) of a star-forming galaxy at $z\approx 0.8$. The CGM of this galaxy is probed by a spatially extended bright background gravitationally lensed arc at $z = 2.76$. The background arc continuously samples the CGM of the foreground galaxy at a range of impact parameters between 54-66 kpc. The Mg II absorption strengths vary by more than a factor of two within these ranges. A power-law fit to the fractional variation of absorption strengths yields a coherence length of 2.7 kpc within these absorption lines. This suggests a high degree of spatial coherence in the CGM of this galaxy. The host galaxy is driving a strong galactic outflow with a mean outflow velocity $\approx$ -179 km/s and mass outflow rate $\dot{M}_{out}\geq 64_{-27}^{+31} M_{\odot}yr^{-1}$ traced by blueshifted Mg II and Fe II absorption lines. The galaxy itself has a spatially extended emission halo with a maximum spatial extent of $\approx$ 33 kpc traced by [O II], [O III] and $Hβ$ emission lines. The extended emission halo shows kinematic signatures of co-rotating halo-gas with solar metallicity. Taken together, these observations suggest evidence of a baryon cycle that is recycling the outflowing gas to form the next generation of stars. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2501_17940 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Spatially Resolved Circumgalactic Medium around a Star-Forming Galaxy Driving a Galactic Outflow at $z\approx 0.8$ Shaban, Ahmed Bordoloi, Rongmon O'Meara, John M. Sharon, Keren Tejos, Nicolas Lopez, Sebastian Ledoux, Cédric Barrientos, L. Felipe Rigby, Jane R. Astrophysics of Galaxies We report the small-scale spatial variation in cool ($T\sim 10^4 K$) Mg II absorption detected in the circumgalactic medium (CGM) of a star-forming galaxy at $z\approx 0.8$. The CGM of this galaxy is probed by a spatially extended bright background gravitationally lensed arc at $z = 2.76$. The background arc continuously samples the CGM of the foreground galaxy at a range of impact parameters between 54-66 kpc. The Mg II absorption strengths vary by more than a factor of two within these ranges. A power-law fit to the fractional variation of absorption strengths yields a coherence length of 2.7 kpc within these absorption lines. This suggests a high degree of spatial coherence in the CGM of this galaxy. The host galaxy is driving a strong galactic outflow with a mean outflow velocity $\approx$ -179 km/s and mass outflow rate $\dot{M}_{out}\geq 64_{-27}^{+31} M_{\odot}yr^{-1}$ traced by blueshifted Mg II and Fe II absorption lines. The galaxy itself has a spatially extended emission halo with a maximum spatial extent of $\approx$ 33 kpc traced by [O II], [O III] and $Hβ$ emission lines. The extended emission halo shows kinematic signatures of co-rotating halo-gas with solar metallicity. Taken together, these observations suggest evidence of a baryon cycle that is recycling the outflowing gas to form the next generation of stars. |
| title | Spatially Resolved Circumgalactic Medium around a Star-Forming Galaxy Driving a Galactic Outflow at $z\approx 0.8$ |
| topic | Astrophysics of Galaxies |
| url | https://arxiv.org/abs/2501.17940 |