1. Radio Properties of Type 2 Active Galactic
Nuclei and How They May Relate to Outflows
Julia Fowler
Department of Physics and Astronomy
Tufts University
Senior Thesis Defense

2. Outline
1 Terminology
• Radio Flux
• Active Galactic Nuclei and Radio Jets
• Spectral Indecies and Spectral Energy Distributions
2 Motivation
• Gas Outflows and Galaxy Evolution
• Properties of Higher Frequency Radio Intermediate Objects
3 Data and Analysis
• Sample Selection
• Radio Interferometry
• Flux Calibration
• UV Distance to Degrees on the Sky
• Self Calibration and Final Images
• Luminosity Calculations

3. Outline Continued
5 Comparisons and Correlations
• High Frequency Radio Properties in Lal et al. 2010
• Bimodal Distributions of Spectral Indecies
• SED Upturns
• Luminosity Correlations with Upturns
• Radio Loud and Radio Quiet Populations
• As For the Outflows
6 Conclusions

4. Terminology

5. Radio Flux
Image Courtesy of Victor Blacus

6. Active Galactic Nuclei and Radio Jets
AGN Up Close
Image Courtesy of C. M. Urry and P. Padovani
Diagram Courtesy of scienceworldreport.com
Formation of a Radio Jet

7. Spectral Indicies and Spectral Energy Distributions
Sν ∝ να
α =
log(Sν1 /Sν2 )
log(ν1/ν2)
Steep Spectrum SED for J171530
Figure Courtesy of NED

8. Motivation

9. Gas Outflows and Galaxy Evolution
Hercules Galaxy – Gas Outflows
Image Courtesy of the NRAO/AUI
Blueshifted OIII Lines

10. Radio Loud and Radio Quiet Populations
Distinct Radio Loud and Quiet
Populations
• In the radio loud case, radio
jets can power gas outflows,
with as little as 40 %
efficiency.
• But radio loud AGN only
make up 90 % of AGN.

11. Data And Analysis

12. Sample Selection
Selection Based on Variation of 6
Objects
Figure Courtesy of Lacy et. al. 2013
• Set of 40 mid-IR Selected
Type 2 AGN.
• Proposed observations in the
S(3GHz) and X(10GHz)
bands.
• Objects chosen in the LH
and XFLS, to have
accompanying data in the
Far-IR and low frequency
radio.
• Due to government shut
down, we got 29 of our
objects in either the S or X
bands.

13. Radio Interferometry
27 Antennas at the Very Large Array
Image Courtesy of the NRAO/AUI
Image Courtesy of metro.co.uk
The Moon : About .5 Degrees in
the Sky

14. Flux Calibration
J1331 Before and After Applying Flux Corrections

15. UV Distance to Degrees on the Sky
Flux Measurements With
Respect to UV Distance
I(l,m) = V (u, v)e[2πi(ul+vm)]dudv
Antenna Set Up for Data Collection

16. Self Calibration and Final Images

17. Luminosity Calculations
[OIII] Luminosity
5GHz Rest Frame Luminosity
L = 4πD2
L
1
1+z
1+α
νobv
νcalc
α
Sνobv
250 µm Luminosity
L(νe) =
4πD2
L
1+z S(νo)

18. Comparisons and Correlations

19. High Frequency Radio Properties and Lal et al. 2010
Bimodal α Distribution
Figure Courtesy of Lal et al. 2010
Figure Courtesy of Lal et al. 2010
Straddling Radio Loud and Quiet
Divide

20. Bimodal Distributions of Spectral Indecies
Our Own Bimodal Sample
Comparison to Lal et al. 2010
Distribution

21. Upturns in Spectral Energy Distribution
SEDs for J171151 and SW105019 Exhibiting Upturn

22. Luminosity Correlations with Upturns
Upturns Correlate with Higher Radio Luminosity and Lower [OIII]
Luminosity

23. Radio Loud and Radio Quiet Populations
Luminosities Peak in Radio
Intermediate Regime
Comparison of Sample with Lal et
al. 2010

24. As for the Outflows
Slight Trend of Lower IR and [OIII] Luminosities with Outflows

25. Conclusions

26. Conclusions
1 High Frequency Radio Properties
• We find a bimodal α distribution.
• 60% of our sources with SEDs show upturns.
• Upturns correlate with higher radio and lower [OIII]
Luminosities
• Our sample defies a distinct division between radio loud and
radio quiet distributions.
2 Gas Outflows
• We find slight trend of lower IR and [OIII] Luminosities
correlating with outflows.
• No effect is clearly dominant in powering outflows.
• More data may confirm that all three effects are vital to power
outflows.

27. Acknowledgements
Professor Sajina
The Physics Astronomy Department
Summer Scholars
Everyone Here