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arXiv · 2108.11958

A Near-Infrared Search for Molecular Gas in the Fermi Bubbles

Andrew J. Fox·Nimisha Kumari·Trisha Ashley·Sara Cazzoli·Rongmon Bordoloi
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Abstract

We present Gemini/NIFS near-IR integral field spectroscopy of the fields-of-view around two AGNs behind the Fermi Bubbles (PDS 456 and 1H1613-097) to search for molecular gas in the Milky Way's nuclear wind. These two AGN sightlines were selected by the presence of high-velocity neutral and ionized gas seen in UV absorption. We do not detect any extended emission from the H2 ro-vibrational S(0) and S(1) lines at 2.224 and 2.122 microns in either direction. For the S(1) line, the 3-sigma surface brightness limits derived from spectra extracted across the full 3x3 arcsecond NIFS field-of-view are 2.4e-17 erg/cm2/s/A/arcsec2 for PDS 456 and and 4.9e-18 erg/cm2/s/A/arcsec2 for 1H1613-097. Given these non-detections, we conclude that CO emission-line studies and H2 UV absorption-line studies are more promising approaches for characterizing the molecular gas in the Fermi Bubbles.

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Andrew J. Fox, Nimisha Kumari, Trisha Ashley, Sara Cazzoli, Rongmon Bordoloi. 2021-08-26. A Near-Infrared Search for Molecular Gas in the Fermi Bubbles. https://doi.org/10.3847/2515-5172%2Fac205d

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