Back to Search
Start Over
Repeating flaring activity of the blazar AO 0235+164.
- Source :
- Astronomy & Astrophysics / Astronomie et Astrophysique; 1/27/2024, Vol. 682, p1-23, 23p
- Publication Year :
- 2024
-
Abstract
- Context. Blazar AO 0235+164, located at a redshift of z = 0.94, has undergone several sharp multi-spectral-range flaring episodes over recent decades. In particular, the episodes that peaked in 2008 and 2015, which were subject to extensive multi-wavelength coverage, exhibited an interesting behavior. Aims. We study the actual origin of these two observed flares by constraining the properties of the observed photo-polarimetric variability as well as of the broadband spectral energy distribution and the observed time-evolution behavior of the source. We use ultra-high-resolution total-flux and polarimetric very-long-baseline interferometry (VLBI) imaging. Methods. The analysis of VLBI images allowed us to constrain kinematic and geometrical parameters of the 7 mm jet. We used the discrete correlation function to compute the statistical correlation and the delays between emission at different spectral ranges. The multi-epoch modeling of the spectral energy distributions allowed us to propose specific models of the emission; in particular, with the aim to model the unusual spectral features observed in this source in the X-ray region of the spectrum during strong multi spectral-range flares. Results. We find that these X-ray spectral features can be explained by an emission component originating in a separate particle distribution than the one responsible for the two standard blazar bumps. This is in agreement with the results of our correlation analysis, where we did not find a strong correlation between the X-ray and the remaining spectral ranges. We find that both external Compton-dominated and synchrotron self-Compton-dominated models are able to explain the observed spectral energy distributions. However, the synchrotron self-Compton models are strongly favored by the delays and geometrical parameters inferred from the observations. [ABSTRACT FROM AUTHOR]
- Subjects :
- SPECTRAL energy distribution
STATISTICAL correlation
X-ray spectra
IMAGE analysis
Subjects
Details
- Language :
- English
- ISSN :
- 00046361
- Volume :
- 682
- Database :
- Complementary Index
- Journal :
- Astronomy & Astrophysics / Astronomie et Astrophysique
- Publication Type :
- Academic Journal
- Accession number :
- 175722688
- Full Text :
- https://doi.org/10.1051/0004-6361/202346885