Velocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core System
This paper presents the detection of a significant velocity offset between the emission and absorption lines of a dual core system in SDSS J155708.82+273518.74 (=SDSS J1557). The photometric image of SDSS J1557 exhibits two clear cores with a projected separation of ∼2.″2 (4.9 kpc) determined by GAL...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2023-01-01
|
| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/acaafe |
| _version_ | 1797702078290722816 |
|---|---|
| author | Qi Zheng Shuang Liu Xueguang Zhang Qirong Yuan |
| author_facet | Qi Zheng Shuang Liu Xueguang Zhang Qirong Yuan |
| author_sort | Qi Zheng |
| collection | DOAJ |
| description | This paper presents the detection of a significant velocity offset between the emission and absorption lines of a dual core system in SDSS J155708.82+273518.74 (=SDSS J1557). The photometric image of SDSS J1557 exhibits two clear cores with a projected separation of ∼2.″2 (4.9 kpc) determined by GALFIT. Based on the applications of the commonly accepted pPXF code with 636 theoretical SSP templates, the host galaxy contribution can be well determined. Then, the emission-line features of SDSS J1557 can be well measured after subtraction of the host starlight. It is found that the velocity offset of emission lines with respect to absorption lines reaches 458 ± 13 km s ^−1 . According to a Baldwin–Phillips–Terlevich diagram, SDSS J1557 is a composite galaxy. In addition, SDSS J1557 can well fit the M _BH − σ _* relation of bulges, and a galaxy merger would not change this relation. Two reasonable models (an AGN-driven outflow versus a dual core system) are discussed to explain this velocity offset. The model of an AGN-driven outflow fails to interpret the systematic redshift of the emission lines and similar velocity offsets for the various emission lines of SDSS J1557. Instead, the significant velocity offset between the emission and absorption lines might be an effective indicator of a dual core system. |
| first_indexed | 2024-03-12T04:44:58Z |
| format | Article |
| id | doaj.art-6395e3748f7448828cad697b384a9a60 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-12T04:44:58Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-6395e3748f7448828cad697b384a9a602023-09-03T09:29:26ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-019441410.3847/1538-4357/acaafeVelocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core SystemQi Zheng0https://orcid.org/0000-0003-4583-3383Shuang Liu1Xueguang Zhang2Qirong Yuan3https://orcid.org/0000-0002-9244-3938School of Physics and Technology, Nanjing Normal University , No. 1, Wenyuan Road, Nanjing, 210023, People's Republic of China ; xgzhang@njnu.edu.cn, yuanqirong@njnu.edu.cnPurple Mountain Observatory , Chinese Academy of Sciences, 10 Yuanhua Road, Nanjing, Jiangsu 210023, People's Republic of China; School of Astronomy and Space Sciences, University of Science and Technology of China , Hefei, Anhui 230026, People's Republic of ChinaSchool of Physics and Technology, Nanjing Normal University , No. 1, Wenyuan Road, Nanjing, 210023, People's Republic of China ; xgzhang@njnu.edu.cn, yuanqirong@njnu.edu.cn; Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University , Nanning, 530004, People's Republic of ChinaSchool of Physics and Technology, Nanjing Normal University , No. 1, Wenyuan Road, Nanjing, 210023, People's Republic of China ; xgzhang@njnu.edu.cn, yuanqirong@njnu.edu.cnThis paper presents the detection of a significant velocity offset between the emission and absorption lines of a dual core system in SDSS J155708.82+273518.74 (=SDSS J1557). The photometric image of SDSS J1557 exhibits two clear cores with a projected separation of ∼2.″2 (4.9 kpc) determined by GALFIT. Based on the applications of the commonly accepted pPXF code with 636 theoretical SSP templates, the host galaxy contribution can be well determined. Then, the emission-line features of SDSS J1557 can be well measured after subtraction of the host starlight. It is found that the velocity offset of emission lines with respect to absorption lines reaches 458 ± 13 km s ^−1 . According to a Baldwin–Phillips–Terlevich diagram, SDSS J1557 is a composite galaxy. In addition, SDSS J1557 can well fit the M _BH − σ _* relation of bulges, and a galaxy merger would not change this relation. Two reasonable models (an AGN-driven outflow versus a dual core system) are discussed to explain this velocity offset. The model of an AGN-driven outflow fails to interpret the systematic redshift of the emission lines and similar velocity offsets for the various emission lines of SDSS J1557. Instead, the significant velocity offset between the emission and absorption lines might be an effective indicator of a dual core system.https://doi.org/10.3847/1538-4357/acaafeActive galactic nucleiActive galaxiesEmission line galaxiesSupermassive black holesGalaxy mergersQuasar absorption line spectroscopy |
| spellingShingle | Qi Zheng Shuang Liu Xueguang Zhang Qirong Yuan Velocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core System The Astrophysical Journal Active galactic nuclei Active galaxies Emission line galaxies Supermassive black holes Galaxy mergers Quasar absorption line spectroscopy |
| title | Velocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core System |
| title_full | Velocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core System |
| title_fullStr | Velocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core System |
| title_full_unstemmed | Velocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core System |
| title_short | Velocity Offset Between Emission and Absorption Lines Might Be an Effective Indicator of a Dual Core System |
| title_sort | velocity offset between emission and absorption lines might be an effective indicator of a dual core system |
| topic | Active galactic nuclei Active galaxies Emission line galaxies Supermassive black holes Galaxy mergers Quasar absorption line spectroscopy |
| url | https://doi.org/10.3847/1538-4357/acaafe |
| work_keys_str_mv | AT qizheng velocityoffsetbetweenemissionandabsorptionlinesmightbeaneffectiveindicatorofadualcoresystem AT shuangliu velocityoffsetbetweenemissionandabsorptionlinesmightbeaneffectiveindicatorofadualcoresystem AT xueguangzhang velocityoffsetbetweenemissionandabsorptionlinesmightbeaneffectiveindicatorofadualcoresystem AT qirongyuan velocityoffsetbetweenemissionandabsorptionlinesmightbeaneffectiveindicatorofadualcoresystem |