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arXiv · 2504.20611

Multi-Component Ionized Gas Outflows in a Hot Dust-Obscured Galaxy W2026+0716 with Keck/OSIRIS

Chao Liu·Chao-Wei Tsai·Peter R. M. Eisenhardt·Hyunsung D. Jun·Guodong Li·Jingwen Wu·Roberto J. Assef·Andrew W. Blain·Maren Cosens·Tanio Díaz-Santos·Román Fernández Aranda·Lei Hao·Mai Liao·Shuai Liu·Daniel Stern·Andrey Vayner·Shelley Wright·Sherry Yeh
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Abstract

We present narrowband-filtered integral field unit (IFU) observations of the Hot Dust-Obscured Galaxy (Hot DOG) WISE J202615.27$+$071624.0 (hereafter W2026$+$0716) at redshift $z=2.570$ using Keck/OSIRIS. Our analysis reveals a multi-component ionized gas outflow structure in this heavily obscured AGN host galaxy. Multi-component Gaussian decomposition of the [O III] and H$\alpha$ emission lines uncovers extremely broad and asymmetric profiles, characteristic of AGN-driven outflows. Kinematic mapping shows spatially distinct structures: the [O III] and H$\alpha$ dominated components (with radii of $1.20 \pm 0.56$ kpc) are separated by a projected offset of $\sim 1.1$ kpc and exhibit divergent velocity regimes. The [O III] outflow reaches a velocity of 3210 $\pm$ 50 km s$^{-1}$, while the H$\alpha$ outflow component attains 2310 $\pm$ 840 km s$^{-1}$. Dynamical modeling supports a biconical outflow structure, with [O III] and H$\alpha$ emissions dominating separate cones and significant dust obscuration of the redshifted outflow. Their comparable momentum outflow rates and energy outflow rates suggest a potential physical connection in their driving mechanisms. Spectral energy distribution (SED) analysis reveals anomalous optical/UV excess, attributed to AGN photon scattering by dust or outflowing material, classifying W2026+0716 as a "Blue Hot DOG". The derived outflow timescale ($\sim10^{5}$ yr) aligns with the evolutionary phase of Blue Hot DOGs, suggesting AGN feedback operates persistently during this transitional stage.

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Chao Liu, Chao-Wei Tsai, Peter R. M. Eisenhardt, Hyunsung D. Jun, Guodong Li, Jingwen Wu, Roberto J. Assef, Andrew W. Blain, Maren Cosens, Tanio Díaz-Santos, Román Fernández Aranda, Lei Hao, Mai Liao, Shuai Liu, Daniel Stern, Andrey Vayner, Shelley Wright, Sherry Yeh. 2025-04-29. Multi-Component Ionized Gas Outflows in a Hot Dust-Obscured Galaxy W2026+0716 with Keck/OSIRIS. https://arxiv.org/abs/2504.20611

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