Details

Autor(en) / Beteiligte

• Vargas, Carlos J.
• Mora-Partiarroyo, Silvia Carolina
• Schmidt, Philip
• Rand, Richard J.
• Stein, Yelena
• Walterbos, René A. M.
• Wang, Q. Daniel
• Basu, Aritra
• Patterson, Maria
• Kepley, Amanda
• Beck, Rainer
• Irwin, Judith
• Heald, George
• Li, Jiangtao
• Wiegert, Theresa

Titel

CHANG-ES X: Spatially Resolved Separation of Thermal Contribution from Radio Continuum Emission in Edge-on Galaxies

Ist Teil von

• The Astrophysical journal, 2018-02, Vol.853 (2), p.128

Ort / Verlag

Philadelphia: The American Astronomical Society

Erscheinungsjahr

2018

Link zum Volltext

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• We analyze the application of star formation rate calibrations using H and 22 m infrared (IR) imaging data in predicting the thermal radio component for a test sample of three edge-on galaxies (NGC 891, NGC 3044, and NGC 4631) in the Continuum Halos in Nearby Galaxies-an EVLA Survey (CHANG-ES). We use a mixture of H and 24 m calibration from Calzetti et al. and a linear 22 m only calibration from Jarrett et al. on the test sample. We apply these relations on a pixel-to-pixel basis to create thermal prediction maps in the two CHANG-ES bands: L and C band (1.5 GHz and 6.0 GHz, respectively). We analyze the resulting nonthermal spectral index maps, and find a characteristic steepening of the nonthermal spectral index with vertical distance from the disk after application of all methods. We find possible evidence of extinction in the 22 m data as compared to 70 m Spitzer Multiband Imaging Photometer imaging in NGC 891. We analyze a larger sample of edge-on and face-on galaxy 25-100 m flux ratios, and find that the ratios for edge-ons are systematically lower by a factor of 1.36, a result we attribute to excess extinction in the mid-IR in edge-ons. We introduce a new calibration for correcting the H luminosity for dust when galaxies are edge-on or very dusty.