Radiative Transfer Modeling of Radio-Band Linear Polarization Observations as a Probe of the Physical Conditions in the Jets of γ-Ray Flaring Blazars
Abstract
:1. Introduction
2. The Model and Method
3. Results
3.1. Single-Epoch Modeling: Study of Jet Properties during the Fermi Era
3.2. Multi-Epoch Modeling: Internal Changes in the Jet on Timescales of Years to Decades
3.3. Inclusion of a Helical Magnetic Field Component
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Model Parameter | UMRAO Data Constraint |
---|---|
Low energy cutoff () | EVPA Spectral Behavior |
Bulk Lorentz Factor () | P% |
Viewing Angle (θ) | P% |
Axial B Field (B) | EVPA and P% |
Shock obliquity (η) | ΔEVPA |
Shock compression (κ) | ΔS and P% |
Shock onset (t) | Start of flare in S or P |
Shock length (l) | Duration of flare in S |
Shock sense (F or R) | Doppler factor and |
Parameter | 0420-014 | OJ 287 | 1156+295 Flare2 | 0716+714 |
---|---|---|---|---|
Cutoff Lorentz Factor | 50 | 10 | 50 | 50 |
Bulk Lorentz Factor | 5 | 5 | 10 | 20 |
Viewing Angle | 4 | 1.5 | 2.0 | 12 |
Axial B (energy density) | 16% | 50% | 50% | 36% |
Shock Sense | F | F | F | F |
Number of Shocks | 3 | 3 | 4 | 8 |
Shock Obliquity | 90 | 30 | 90 | 90 |
Shock Compression | 0.65–0.8 | 0.5–0.7 | 0.5–0.8 | 0.17–0.27 |
Shock (in units of c) | 11 | 17 | 22 | 9.5 |
Parameter | T1985 | T2008 | T2010 |
---|---|---|---|
Cutoff Lorentz Factor () | 50 | 50 | 50 |
Bulk Lorentz Factor | 5 | 10 | 10 |
Viewing Angle | 1.7 | 1.4 | 1.1 |
Axial B field (B) | 25% | 64% | 56% |
Shock Sense | F | F | F |
Number of Shocks | 5 | 6 | 3 |
Shock Obliquity | 90 | 90 | 90 |
Shock Compression | 0.28–0.40 | 0.35–0.65 | 0.3–0.4 |
Shock Lorentz Factor | 14.5 | 24.7 | 27.3 |
Shock | 10.4 | 21.8 | 22.5 |
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Aller, M.F.; Hughes, P.A.; Aller, H.D.; Hovatta, T.; Ramakrishnan, V. Radiative Transfer Modeling of Radio-Band Linear Polarization Observations as a Probe of the Physical Conditions in the Jets of γ-Ray Flaring Blazars. Galaxies 2016, 4, 35. https://doi.org/10.3390/galaxies4040035
Aller MF, Hughes PA, Aller HD, Hovatta T, Ramakrishnan V. Radiative Transfer Modeling of Radio-Band Linear Polarization Observations as a Probe of the Physical Conditions in the Jets of γ-Ray Flaring Blazars. Galaxies. 2016; 4(4):35. https://doi.org/10.3390/galaxies4040035
Chicago/Turabian StyleAller, Margo F., Philip A. Hughes, Hugh D. Aller, Talvikki Hovatta, and Venkatessh Ramakrishnan. 2016. "Radiative Transfer Modeling of Radio-Band Linear Polarization Observations as a Probe of the Physical Conditions in the Jets of γ-Ray Flaring Blazars" Galaxies 4, no. 4: 35. https://doi.org/10.3390/galaxies4040035