A method for identification of restarted radio sources from large radiosurveys
- Title
- A method for identification of restarted radio sources from large radiosurveys
- Creator
- Raj A.; Ishwara-Chandra C.H.; Sudheesh T.P.; Biju K.G.; Jacob J.
- Description
- Active galaxies hosting radio jets can exhibit distinct active phases marked by two sets of radio lobes. Typically, these episodic radio sources have been identified through morphological observations. In addition, spectral characteristics-based methods are also employed wherever multi-frequency deep radio observations are available. However, these methods are inefficient in detecting restarted radio sources that do not exhibit a clear morphology. To address this, a method of using the spectral curvature (SPC=?150MHz1400MHz-?74MHz150MHz) to identify restarted radio sources is presented. This is based on the fact that restarted radio sources with significant remnant emission are expected to have concave spectra in contrast to the convex or straight spectra observed in most radio sources. We use available wide area radio surveys in the range of frequencies from 74MHz to 1.4GHz to search for episodic radio sources and to shortlist 9,405 sources based on the criteria of SPC?0.5. The candidates thus identified can be followed up for detailed morphological and spectral index studies. This method will find application in the automated identification of episodic radio sources in large radio sky surveys from telescopes like LOFAR and SKA. Indian Academy of Sciences 2025.
- Source
- Journal of Astrophysics and Astronomy, Vol-46, No. 1
- Date
- 2025-01-01
- Publisher
- Springer
- Subject
- catalogs; galaxies: active; radio continuum: galaxies; Surveys
- Coverage
- Raj A., Newman College, Thodupuzha, 685584, India, K. E. College, Mannanam, 686561, India; Ishwara-Chandra C.H., National Centre for Radio Astrophysics, TIFR, Post Bag No. 3, Ganeshkhind, Pune, 411007, India; Sudheesh T.P., Christ (Deemed to be University), Hosur Rd, Bengaluru, 560029, India; Biju K.G., WMO Arts, and Science college, Muttil, Wayanad, 673122, India; Jacob J., Newman College, Thodupuzha, 685584, India
- Rights
- Restricted Access
- Relation
- ISSN: 2506335
- Format
- Online
- Language
- English
- Type
- Article
Collection
Citation
Raj A.; Ishwara-Chandra C.H.; Sudheesh T.P.; Biju K.G.; Jacob J., “A method for identification of restarted radio sources from large radiosurveys,” CHRIST (Deemed To Be University) Institutional Repository, accessed February 24, 2025, https://archives.christuniversity.in/items/show/12493.