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arXiv · 2511.13585

High Resolution Observations of CO(3-2) in Haro 2: Cool Molecular Outflows of a Ly$\alpha$ Emitter

Sara Beck·Pei-Ying Hsieh·Jean Turner
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Abstract

Haro 2 is a blue compact dwarf galaxy and the closest (at 21Mpc) known $Ly\alpha$ emitter. UV and optical observations have found Haro 2 to be immersed in shells of partly ionized gas expanding at $\sim200$km/s. Observations of CO(2-1) (Becket et al 2020; Paper 1) with moderate ($2^{\prime\prime}$) resolution discovered a large-scale one-sided outflow associated with a soft X-ray bubble and apparently driven by the young star clusters created in the recent starburst. We present here SMA observations of CO(3-2) with $1.1^{\prime\prime}$ resolution in Haro 2. The opposite-side component of the large molecular outflow is detected lying in the direction of the fast ionized outflow; it is very confined in area. An additional outflow is apparent in the CO(3-2); it is south-east of the galaxy in a region holding weak star formation and a moderate-luminosity hard X-ray source. All the molecular outflow and filament velocities are within $\lesssim\pm50$km/s of the systemic velocity of the galaxy.

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Sara Beck, Pei-Ying Hsieh, Jean Turner. 2025-11-17. High Resolution Observations of CO(3-2) in Haro 2: Cool Molecular Outflows of a Ly$\alpha$ Emitter. https://arxiv.org/abs/2511.13585

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