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arXiv · 2303.05531

Characterizing the Circumgalactic Medium of Quasars at z $\sim$ 2.2 through H$\alpha$ and Ly$\alpha$ Emission

Vivienne Langen·Sebastiano Cantalupo·Charles C. Steidel·Yuguang Chen·Gabriele Pezzulli·Sofia G. Gallego
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Abstract

The discovery of giant quasar Ly$\alpha$ nebulae at $z>2$ has opened up the possibility to directly study in emission the Circumgalactic and Intergalactic Medium (CGM/IGM). However, the resonant nature of the Ly$\alpha$ line and its different emission mechanisms hamper the ability to constrain both the kinematics and physical properties of the CGM/IGM. Here, we present results of a pilot project aiming at the detection of CGM H$\alpha$ emission, a line which does not suffer from these limitations. To this end, we first used KCWI to detect Ly$\alpha$ emission around three bright quasars with $2.25 10^{12}$M$_{\odot}$).

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Vivienne Langen, Sebastiano Cantalupo, Charles C. Steidel, Yuguang Chen, Gabriele Pezzulli, Sofia G. Gallego. 2023-03-09. Characterizing the Circumgalactic Medium of Quasars at z $\sim$ 2.2 through H$\alpha$ and Ly$\alpha$ Emission. https://doi.org/10.1093/mnras%2Fstac3205

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