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

First listed 2026-04-16 | Last updated 2026-04-16

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.

Short digest

This paper searches for lower-redshift analogues of little red dots in DESI in order to test whether the LRD phenomenon has a later evolutionary counterpart. The main result is that the selected low-redshift objects reproduce some headline LRD traits, but they also differ in key line-ratio and host-galaxy diagnostics, so the analogy is suggestive rather than exact. The paper matters because it offers an observationally easier comparison set while also warning that not every red compact broad-line source should be treated as the same physical class.

Key figures to inspect

No figure recommendations stored yet.