| Name: | MOUSUMI DAS |
| Affiliation: | Indian Institute of Astrophysics |
| Conference ID : | ASI2024_898 |
| Title : | The Sample of Dual AGN in the GOTHIC survey and its Implications for Understanding Galaxy Evolution |
| Authors : | Anwesh Bhattacharya (BITS-Pilani), Nehal C.P. (IISER-Bhopal), Abhishek Paswan (Univ. of Allahabad), Snehanshu Saha (BITS-Goa), Francoise Combes (Observatoire de Paris).
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| Authors Affiliation: | Mousumi Das (Indian Institute of Astrophysics)
Anwesh Bhattacharya (BITS-Pilani)
Nehal C.P. (IISER-Bhopal)
Abhishek Paswan (Univ. of Allahabad)
Snehanshu Saha (BITS-Goa)
Francoise Combes (Observatoire de Paris).
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| Mode of Presentation: | Poster |
| Abstract Category : | Galaxies and Cosmology |
| Abstract : | As galaxies merge their nuclei come closer and eventually become bound in a common envelope. During this process the nuclei may start accreting mass and become active galactic nuclei (AGN). So there can be pairs of AGN (also called dual AGN), starburst-AGN pairs and star forming nuclei pairs in merger remnants. Although galaxy mergers are common, dual AGN appear to be rare. But their detection is important because they help us understand the formation of supermassive black hole (SMBH) binaries, SMBH growth and AGN feedback in multiple nuclei systems. We have done a systematic survey of existing imaging data for the discovery of dual nuclei in closely merging galaxies, called the GOTHIC survey (since it uses an algorithm called GOTHIC). We have detected 159 dual AGN in this sample, of which 2 are triple AGN systems. Our results show that dual AGN are not common, and triple AGN even rarer. The color (u-r) magnitude plots of the closely merging galaxies shows that star formation is quenched as dual the AGN fraction increases. The dual AGN galaxies mainly lie in the red sequence, whereas the star forming pairs lie in the blue cloud. We also find that dual AGN are mainly found in major mergers of galaxies as their galaxy mass ratios are greater than 0.4. We discuss what this survey reveals about galaxy mergers, bulge growth and SMBH distribution in our low redshift universe. |
