Table · dataset · 2026
KVN CLEAN images of PKS 1222+216
Listed in IVOA Registry (Virtual Observatory)
We present a multi-wavelength study of the Flat Spectrum Radio Quasar PKS 1222+216, analyzing its long-term variability of radio data obtained in 2013-2020 from the iMOGABA, MOJAVE, and VLBA-BU-BLAZAR programs, along with Gamma-ray data from Fermi-LAT.
Description
We found that the radio flux densities at 15, 22, 43, and 86GHz declined exponentially by 37%-56% over a year following a Gamma-ray flare in November 2014. We estimated jet physical parameters through Gaussian model fitting of VLBA 43GHz data, identifying 10 jet components.
The cooling timescales of the jet emission regions, i.e., newly ejected components C9, C10, and C11, range from 43 to 222 days, with the estimated jet viewing angles of approximately 8 degrees and magnetic field strengths of 77-134mG in the jet emission regions. Additionally, by determining the magnetic field strength at different frequencies, we found that the magnetic field scales as B {prop.to} r^(-0.3+/-0.04)^, indicating a non-equipartition condition (kr>~1) or a slow decline in magnetic field strength profile (m<1).
Read the rest (2 more)
By analyzing component ejection times, we discovered that the Gamma-ray flare in 2014 coincided with the interaction between the moving component C9 and the stationary feature A1. We estimated that the Gamma-ray emission region is located at 9.2+/-1.0pc from the core, beyond the BLR and dusty torus, suggesting that the seed photons for inverse Compton scattering originate from the jet itself, external CMB radiation, or a surrounding sheath.
Our results favor a scenario where Gamma-ray emission originates further downstream from the central engine through interactions between moving and stationary components. Additionally, our study presents an alternative method for estimating magnetic field strengths in AGNs undergoing long-term synchrotron cooling based on the associated timescale.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/708/A339 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 2026A&A...708A.339J ui.adsabs.harvard.edu/abs/2026A%26A...708A.339J ↗
publication · from IVOA Registry
Catalogue records · 2
- VOResource record dc.g-vo.org/oai.xml?verb=GetRecord&metadataPrefix=ivo_vor&identifier=ivo%3… ↗
metadata API · from IVOA Registry
- Registry record (GAVO) dc.g-vo.org/I/cds.vizier/j/a%2Ba/708/a339 ↗
catalogue entry · from IVOA Registry
Topics
- From keywords
- Astronomy & Astrophysics
- Inferred from text
- Astronomical sciences 68% · Image 65%
Provenance · 1 source records, 11 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/a+a/708/a339 | 13 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[field].anzsrc:group:5101 | enrichment · IVOA Registry | taxonomy-embedding@1.1.0 | title+keywords+description (68%) |
| concepts[field].local:field:astronomy | mapping · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:gamma-ray | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:radio | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].local:modality:image | enrichment · IVOA Registry | keyword-concept-rules@1.0.0 | title+description (65%) |
| description | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_description |
| license_text | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| publication_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| title | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_title |
| updated_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 |