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arXiv · 2604.14551

Discovery of low-redshift analogues to "Little Red Dots" in DESI: A later evolutionary stage of compact LRDs?

Weiyu Ding·Xu Kong·Wei-Jian Guo·Hu Zou·Jialai Wang·Fujia Li·Hongxin Zhang·Jie Song·Jingyi Zhang·Niu Li·Wen-Xiong Li
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Abstract

The James Webb Space Telescope (JWST) has recently discovered a population of compact, red sources at z > 4 known as "Little Red Dots" (LRDs). They are characterized by their V-shaped continuum spectra and prominent broad Balmer emission lines. As their underlying physical nature remains debated and direct study at high-redshift is challenging; therefore, we seek to identify and characterize LRD analogues in the low-redshift universe to constrain their properties and potential evolutionary pathways. We identified five candidates at z = 0.2-0.4 from the Dark Energy Spectroscopic Instrument (DESI) that exhibit spectral energy distributions (SEDs) and broad Balmer emission lines closely resembling their high-redshift counterparts. However, we find significant differences: our low-redshift sample occupies a different region on the Baldwin, Phillips \& Terlevich (BPT) diagram, and their stellar masses are significantly higher, suggesting a more substantial host galaxy contribution. These sources are not necessarily direct local analogues of high-redshift LRDs, but may represent later evolutionary stages of compact, rapidly accreting systems, or systems with related observational properties arising under different physical conditions. This sample provides a valuable laboratory for detailed follow-up studies to elucidate the nature of LRD-like phenomena.

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Weiyu Ding, Xu Kong, Wei-Jian Guo, Hu Zou, Jialai Wang, Fujia Li, Hongxin Zhang, Jie Song, Jingyi Zhang, Niu Li, Wen-Xiong Li. 2026-04-16. Discovery of low-redshift analogues to "Little Red Dots" in DESI: A later evolutionary stage of compact LRDs?. https://doi.org/10.1051/0004-6361%2F202557889

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