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arXiv · 2512.16422

MUSE Analysis of Gas around Galaxies (MAGG) -- VII. Emission line galaxies near strong blended Ly$\alpha$ absorption systems at $z\gtrsim3$

Marta Galbiati·Davide Tornotti·Michele Fumagalli·Matteo Fossati·Matthew Pieri
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Abstract

We investigate the connection between strong, blended Ly$\alpha$ absorption systems (SBLAs) and $\approx1000$ Ly$\alpha$ emitting galaxies (LAEs) at $z\gtrsim3$ in 28 quasar fields from the MUSE Analysis of Gas around Galaxies (MAGG) survey. Selecting SBLAs as spectral regions with transmitted flux $-0.05 0.25$. The correlation appears to also depend on the width of the spectral window used to identify SBLAs, with a larger window yielding a stronger signal. Our analysis confirms that SBLAs serve as probes of the CGM at the interface between the Ly$\alpha$ forest and the optically-thick Lyman limit systems. The significant dependence of the LAE-SBLA cross-correlation on the spectral binning used to select these absorbers motivates future tests of the current SBLA framework as a tracer of halos.

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Marta Galbiati, Davide Tornotti, Michele Fumagalli, Matteo Fossati, Matthew Pieri. 2025-12-18. MUSE Analysis of Gas around Galaxies (MAGG) -- VII. Emission line galaxies near strong blended Ly$\alpha$ absorption systems at $z\gtrsim3$. https://doi.org/10.1051/0004-6361%2F202558642

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