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arXiv · 1308.5270

A Multi-Wavelength Analysis of NGC 4178: A Bulgeless Galaxy with an AGN

Nathan Secrest·Shobita Satyapal·Sean Moran·Teddy Cheung·Marcello Giroletti·Mario Gliozzi·Marcel Bergmann·Anil Seth
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Abstract

We present {\it Gemini} longslit optical spectroscopy and VLA radio observations of the nuclear region of NGC 4178, a late-type bulgeless disk galaxy recently confirmed to host an AGN through infrared and X-ray observations. Our observations reveal that the dynamical center of the galaxy is coincident with the location of the {\it Chandra} X-ray point source discovered in a previous work, providing further support for the presence of an AGN. While the X-ray and IR observations provide robust evidence for an AGN, the optical spectrum shows no evidence for the AGN, underscoring the need for the penetrative power of mid-IR and X-ray observations in finding buried or weak AGNs in this class of galaxy. Finally, the upper limit to the radio flux, together with our previous X-ray and IR results, is consistent with the scenario in which NGC 4178 harbors a deeply buried AGN accreting at a high rate.

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Nathan Secrest, Shobita Satyapal, Sean Moran, Teddy Cheung, Marcello Giroletti, Mario Gliozzi, Marcel Bergmann, Anil Seth. 2013-08-24. A Multi-Wavelength Analysis of NGC 4178: A Bulgeless Galaxy with an AGN. https://doi.org/10.1088/0004-637x%2F777%2F2%2F139

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