An Updated Characterization of Luminous Lyα emitters at the End of Reionization

@misc{ning2026updated,
  title = {{An Updated Characterization of Luminous Lyα emitters at the End of Reionization}},
  author = {Yuanhang Ning and Zheng Cai and Linhua Jiang and Qiong Li and Si-Yue Yu and Xiaodi Yu and Zhen-Ya Zheng},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2605.14313},
  eprint = {2605.14313},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2605.14313},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - An Updated Characterization of Luminous Lyα emitters at the End of Reionization
AU  - Yuanhang Ning
AU  - Zheng Cai
AU  - Linhua Jiang
AU  - Qiong Li
AU  - Si-Yue Yu
AU  - Xiaodi Yu
AU  - Zhen-Ya Zheng
PY  - 2026
DA  - 2026/09/16
PB  - arXiv
DO  - 10.48550/arxiv.2605.14313
UR  - https://arxiv.org/abs/2605.14313
AB  - We present a multi-wavelength physical characterization of 14 luminous Lyα emitters (LAEs) at z≈6, integrating deep ground-based Magellan/M2FS spectroscopy with heterogeneous JWST/NIRCam broad- and medium-band imaging. Identified via strong Lyα lines with extreme Lyα luminosities of >10^42.6 erg s^−1, the sample exhibits very large rest-frame equivalent widths (≳100 Å) and steeply blue UV continua (β_median≃−2.2, −18.2>M_1500>−20.2 mag). Crucially, the integration of NIRCam medium-band photometry (F410M) breaks the degeneracy between strong rest-optical nebular emission and Balmer breaks, resolving prior mass overestimations. The tightly constrained spectral energy distribution modeling demonstrates that these luminous LAEs tend to be unequivocally low-mass, ultra-young dwarf starbursts; half the sample is characterized by stellar masses of M_* < 10^8 M_⊙, ages ≲10 Myr, and negligible dust attenuation. We also map the production efficiency of ionizing photons and Lyα escape fractions (f_esc^Lyα). The f_esc^Lyα values are exceptionally high, with a median of ≳40%, increasing for the bluer UV continua. Finally, analyzing spatial offsets between the Lyα centroid and the stellar counterpart, we demonstrate empirically that internal dust content, rather than neutral hydrogen gas, dominate the suppression of Lyα radiative transfer. Our study reveals that strong Lyα emission of the luminous LAEs are generally attributed to both the vigorous starburst activities and the high f_esc^Lyα. Resembling Lyman continuum leakers, these extreme dwarf systems function as highly efficient ionizing engines at the conclusion of the Epoch of Reionization.
ER  -