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arXiv · 2606.25723

Ly$\rm \alpha$ halos and UV continuum morphologies of Tadpole Galaxies at $z> 3$

Manish Kataria·Kanak Saha
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Abstract

Tadpole and clump-chain galaxies are a morphologically distinct population among high-redshift star-forming galaxies whose disturbed structures may influence the escape and propagation of Ly$\alpha$ photons. We investigate the Ly$\alpha$ and UV continuum properties of 12 tadpole galaxies in the redshift range of z $\sim$ 3 -- 5.5 identified in the Hubble Ultra Deep Field (HUDF) using deep MUSE observations. Accounting for their elongated morphologies, we construct surface brightness profiles and characterize the spatial extent of their Ly$\alpha$ emission. Extended Ly$\alpha$ halos are detected in 10 of the 12 galaxies, demonstrating that diffuse Ly$\alpha$ emission is common among tadpole systems. Approximately 40\% of the sample exhibits double-peaked Ly$\alpha$ profiles. While the effective radii ($\rm R_{e}$) of the Ly$\rm \alpha$ emission generally follow the spatial extent of the UV continuum, the Ly$ \rm \alpha$ halos are typically more symmetric and often exhibit spatial offsets from the stellar component. Some galaxies also display asymmetric and outflow-like Ly$\rm \alpha$ structures suggestive of anisotropic escape and complex radiative transfer effects. Together, these results suggest that the disturbed morphologies of tadpole galaxies may influence the transport of Ly$\rm \alpha$ photons and contribute to the formation of extended Ly$\rm \alpha$ halos in the circumgalactic medium.

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Manish Kataria, Kanak Saha. 2026-06-24. Ly$\rm \alpha$ halos and UV continuum morphologies of Tadpole Galaxies at $z> 3$. https://arxiv.org/abs/2606.25723

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