Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2402.10444 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866913235676954624 |
|---|---|
| author | Yi, Weimin Hall, P. B. Yuan, Zunlin Brandt, W. N. Schneider, D. P. He, Zhicheng Bai, Jin-Ming Wu, Xue-Bing |
| author_facet | Yi, Weimin Hall, P. B. Yuan, Zunlin Brandt, W. N. Schneider, D. P. He, Zhicheng Bai, Jin-Ming Wu, Xue-Bing |
| contents | We present an observational study of wind acceleration based on four low-ionization broad absorption line (LoBAL) quasars (J0136, J1238, J1259, J1344). J0136 and J1344 (group-1) are radio quiet and show large BAL-velocity shifts as opposed to stable line-locking associated absorption lines (AALs). Notably, J1344 displays a linear relation between BAL-velocity shift and time interval over three consecutive epochs, characteristic of compelling evidence for BAL acceleration. J1238 and J1259 (group 2) exhibit small BAL-velocity shifts along with steep-spectrum, weak radio emission at 3.0 and 1.4 GHz. All four quasars have spectral energy distributions (SEDs) with a peak at $λ_{\rm rest }\sim10~μ$m, suggesting a link between the BAL acceleration and hot dust emission. The group-2 quasars are redder than group-1 quasars and have a steeper rise at $1<λ_{\rm rest }<3~μ$m in their SEDs. All but J1238 exhibit a steep rise followed by a plateau-like time evolution in BAL-velocity shift. Our investigations, combined with previous studies of BAL acceleration, indicate that (1) the BAL-ISM coupling process is one of the major avenues for the origin of quasar reddening and patchy obscuration, (2) AAL outflows are ubiquitous and likely signify large-scale remnants of BAL winds coupled to interstellar medium (ISM), and (3) wind deceleration that is closely linked to the BAL-ISM coupling process may produce weak radio emission in otherwise radio-quiet quasars. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2402_10444 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Quasar winds caught on acceleration and deceleration Yi, Weimin Hall, P. B. Yuan, Zunlin Brandt, W. N. Schneider, D. P. He, Zhicheng Bai, Jin-Ming Wu, Xue-Bing Astrophysics of Galaxies We present an observational study of wind acceleration based on four low-ionization broad absorption line (LoBAL) quasars (J0136, J1238, J1259, J1344). J0136 and J1344 (group-1) are radio quiet and show large BAL-velocity shifts as opposed to stable line-locking associated absorption lines (AALs). Notably, J1344 displays a linear relation between BAL-velocity shift and time interval over three consecutive epochs, characteristic of compelling evidence for BAL acceleration. J1238 and J1259 (group 2) exhibit small BAL-velocity shifts along with steep-spectrum, weak radio emission at 3.0 and 1.4 GHz. All four quasars have spectral energy distributions (SEDs) with a peak at $λ_{\rm rest }\sim10~μ$m, suggesting a link between the BAL acceleration and hot dust emission. The group-2 quasars are redder than group-1 quasars and have a steeper rise at $1<λ_{\rm rest }<3~μ$m in their SEDs. All but J1238 exhibit a steep rise followed by a plateau-like time evolution in BAL-velocity shift. Our investigations, combined with previous studies of BAL acceleration, indicate that (1) the BAL-ISM coupling process is one of the major avenues for the origin of quasar reddening and patchy obscuration, (2) AAL outflows are ubiquitous and likely signify large-scale remnants of BAL winds coupled to interstellar medium (ISM), and (3) wind deceleration that is closely linked to the BAL-ISM coupling process may produce weak radio emission in otherwise radio-quiet quasars. |
| title | Quasar winds caught on acceleration and deceleration |
| topic | Astrophysics of Galaxies |
| url | https://arxiv.org/abs/2402.10444 |