Local Analogs of Little Red Dots: Clues to the X-Ray Weakness

A major question about JWST’s little red dots (LRDs) at z ∼ 4−8 is the origin of their apparent X-ray weakness. Even deep Chandra stacks yield only tentative detections or broadband limits and cannot distinguish among super-Eddington accretion, intrinsic X-ray weakness, and Compton-thick (CT) obscuration. Local analogs offer a powerful complementary route. At z ∼ 0.3, similarly luminous sources require ∼10 3−4 less exposure for comparable signal-to-noise, suffer less source confusion, and directly probe the diagnostic rest-frame soft X-rays. Here we present a pilot Einstein Probe/FXT study of six “local little red dots” (LLRDs), V-shaped broad-line green pea galaxies selected as low-redshift counterparts of LRDs. These sources show X-ray diversity: “X-normal” LLRDs resemble type 1 active galactic nuclei (AGNs) in X-ray luminosity and optical variability, whereas “X-weak” stack lies ∼0.5–0.7 dex below standard unobscured-quasar scaling relations while remaining compatible with the representative LRD stack and 95% of published individual limits. The X-weak LLRDs also lack detected optical variability and have redder optical continua than X-normal LLRDs, making their V-shaped SEDs closer to those of high-redshift LRDs. The detection of the X-weak stack at ∼3.3 σ with the soft-X-ray-sensitive EP-FXT provides rest-frame ∼2−3 keV constraints difficult to reconcile with a typical unobscured super-Eddington model or a local-AGN-like CT geometry examined here, although modified variants remain possible. The simplest alternative is a mildly X-ray-weak corona (Δ α ox ∼ −0.1 to −0.2) with Compton-thin absorption ( N H ∼ 10 22−23 cm −2 ), consistent with the independent Balmer decrement/break diagnostics. Together with growing samples of local LRD analogs, our results offer a practical path for testing the physical nature of LRD X-ray weakness.