Relation between [OI] 63μm (left panel) and [OI] 145μm (right panel) line luminosity and SFR. Our simulation results at z = 6 are shown as red density contours, with solid lines representing median trends. The median trend of the model with self-absorption neglecting the Eq. (4) condition is shown as a dashed line. Dotted lines are linear fits of the simulation results, with coefficients listed in Section 4.3. Other z ∼ 6 predictions for [OI] 63μm luminosity obtained from the post-processing of numerical simulations are also reported: Olsen et al. (2017) as blue circles and Ramos Padilla et al. (2023) as a turquoise area. Some observations are also reported for reference. The data up to z = 4 compiled by Ramos Padilla et al. (2023) are shown as hexagons. The J2054-00005 at z = 6.04 (Ishii et al. 2025) and W2246-0526 at z = 4.60 (Fernández Aranda et al. 2024) have both [OI] 63μm and [OI] 145μm detections. As for [OI] 145μm, we include the recent 6.5 ≤ z ≤ 7.7 REBELS observations (Fudamoto et al. 2025), the z = 6.00 J2310+1855 QSO (Li et al. 2020), and the new data obtained in this work (A1689-zD1 at z = 7.13, SPT0346−52 at z = 5.7 and J204313.2-214439 at z = 4.68; see Sect. 3).