eROSITA-RU tidal disruption events with Keck-I/LRIS: Sample selection, optical properties, and host galaxy demographics

Context. We selected 70 tidal disruption event (TDE) candidates among X-ray transients discovered during the eROSITA all-sky surveys in the eastern Galactic hemisphere (0° L g , peak . Among the 23 gold TDEs with detected optical flares, delayed X-ray peaks are commonly observed. We identified transient spectral features in eight events, including six with prominent broad He II λ 4686 and/or H α emission and two coronal-line TDEs. Host galaxy demographics revealed modest overrepresentation in green valley (×1.8) and quiescent Balmer-strong (×5.3) galaxies, which is significantly weaker than previous TDE samples, demonstrating greater diversity in star formation histories than previously recognized. Most TDE hosts exhibit suppressed star formation relative to the main sequence, consistent with X-ray selection biases against dusty star-forming galaxies.