Compact Symmetric Objects. I. Toward a Comprehensive Bona Fide Catalog
Creators
-
1.
FORTH Institute of Astrophysics
-
2.
University of Crete
-
3.
Purdue University West Lafayette
-
4.
California Institute of Technology
-
5.
University of Turku
-
6.
University of New Mexico
-
7.
Harvard-Smithsonian Center for Astrophysics
-
8.
University of Manchester
Abstract
Compact symmetric objects (CSOs) are jetted active galactic nuclei (AGN) with overall projected size <1 kpc. The classification was introduced to distinguish these objects from the majority of compact jetted AGN in centimeter-wavelength very long baseline interferometry observations, where the observed emission is relativistically boosted toward the observer. The original classification criteria for CSOs were (i) evidence of emission on both sides of the center of activity and (ii) overall size <1 kpc. However, some relativistically boosted objects with jet axes close to the line of sight appear symmetric and have been misclassified as CSOs, thereby undermining the CSO classification. This is because two essential CSO properties, pointed out in the original papers, have been neglected: (iii) low variability and (iv) low apparent speeds along the jets. As a first step toward creating a comprehensive catalog of "bona fide" CSOs, we identify 79 bona fide CSOs, including 15 objects claimed as confirmed CSOs here for the first time, that match the CSO selection criteria. This sample of bona fide CSOs can be used for astrophysical studies of CSOs without contamination by misclassified CSOs. We show that the fraction of CSOs in complete flux density limited AGN samples with S5GHz > 700 mJy is between (6.8 ± 1.6)% and (8.5 ± 1.8)%.
Acknowledgement
We thank the reviewer of this paper for many helpful suggestions that have clarified several important aspects of this work. This research has made use of NASA's Astrophysics Data System Bibliographic Services. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. The authors are grateful for the use of the CATS database of Verkhodanov et al. (2005), of the Special Astrophysical Observatory. This research has made use of data from the OVRO 40 m monitoring program (Richards et al. 2011), supported by private funding from the California Institute of Technology and the Max Planck Institute for Radio Astronomy, and by NASA grants NNX08AW31G, NNX11A043G, and NNX14AQ89G and NSF grants AST-0808050, AST-1109911, and AST-1835400. This research has made use of data from the MOJAVE database that is maintained by the MOJAVE team (Lister et al. 2018). The MOJAVE program was supported by NASA-Fermi grant 80NSSC19K1579. S.K. and K.T. acknowledge support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program under grant agreement No. 771282. K.T. acknowledges support from the Foundation of Research and Technology—Hellas Synergy Grants Program through project POLAR, jointly implemented by the Institute of Astrophysics and the Institute of Computer Science. A.S. acknowledges support from the NASA contract NAS8-03060 (Chandra X-ray Center). This paper depended on a very large amount of VLBI data, almost all of which were taken with the Very Long Baseline Array. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.
Software References
Astropy (Astropy Collaboration et al. 2013, 2018, 2022), Astroquery (Ginsburg et al. 2019), Matplotlib (Hunter 2007), NumPy (Harris et al. 2020), pandas (McKinney 2010), SciPy (Virtanen et al. 2020), seaborn (Waskom 2021)
Files
Kiehlmann_2024_ApJ_961_240.pdf
Files
(1.4 MB)
| Name | Size | Download all |
|---|---|---|
|
md5:efbbd19d7d4a5106266632705299d73b
|
1.4 MB | Preview Download |
Additional details
Identifiers
- ISSN
- 1538-4357
Related works
- Featured in
- Caltech News: https://www.caltech.edu/about/news/sleeping-supermassive-black-holes-awakened-briefly-by-shredded-stars (URL)
Funding
- National Science Foundation
- AST-0808050
- California Institute of Technology
- Max Planck Institute for Radio Astronomy
- National Aeronautics and Space Administration
- NNX08AW31G
- National Aeronautics and Space Administration
- NNX11A043G
- National Aeronautics and Space Administration
- NNX14AQ89G
- National Science Foundation
- AST-1109911
- National Science Foundation
- AST-1835400
- National Aeronautics and Space Administration
- 80NSSC19K1579
- European Research Council
- 771282
- Foundation for Research and Technology Hellas
- National Aeronautics and Space Administration
- NAS8-03060