Warm Debris Disk Candidates around Nearby FGK Stars from LAMOST DR12

TL;DR

This study systematically identifies 12 warm debris disk candidates around nearby FGK stars using LAMOST, Gaia, and infrared data, providing a reliable sample for future debris disk evolution research.

Contribution

It introduces a homogeneous method combining spectroscopic, astrometric, and infrared data to identify debris disk candidates, including ten new detections.

Findings

Most host stars are several billion years old.

Infrared excesses are confirmed to be circumstellar in origin.

Two candidates have potential wide-separation companions.

Abstract

Warm debris disks around main-sequence stars trace late-stage terrestrial planet formation. Motivated by the need for systematic searches of such systems, we identify debris disk candidates around FGK stars within 150 pc by combining a spectroscopically selected sample from LAMOST DR12 with Gaia astrometry and multi-band infrared photometry. Infrared excesses are identified through SED fitting and validated using conservative, source-by-source checks. This approach yields a final sample of 12 debris disk candidates including ten new detections. Stellar age research indicate that most of the host stars are several billion years old. NEOWISE monitoring reveals no significant W1/W2 variability, consistent with a circumstellar origin of the infrared excess. while a search for co-moving companions using Gaia DR3 reveals possible companions for only two candidates at very large projected separations ($\gtrsim 10^4$~au). Three candidates exhibit excess emission in both the W3 and W4 bands, allowing estimates of characteristic dust properties. This work establishes a small yet reliable sample of debris disk candidates anchored in homogeneous LAMOST spectroscopy, providing a foundation for future studies of debris disk evolution and stellar activity.