OGHReS: Star formation in the Outer Galaxy II (ℓ = 180○-280○)*

The Outer Galaxy High-Resolution Survey (OGHReS) covers 100 square degrees (180○ < ℓ < 280○) in the (2–1) transitions of three CO-isotopologues. We use the spectra to refine the velocities and physical properties to 6 706 Hi-GAL clumps located in the OGHReS region. In a previous paper, we analysed 3 584 clumps between ℓ = 250○ and 280○. Here, we cover a further 3 122 clumps (180○ < ℓ < 250○) and determine reliable velocities for 2 781 of these, finding good agreement with the previously assigned velocities (∼80 per cent within 5 km s−1). We update velocities for 288 clumps and provide new values for an additional 411. Combining these with the previous results, we have velocities and physical properties for 6 193 clumps (92.3 per cent). The 422 non-detections are low surface density clumps or likely contamination by evolved stars and galaxies. Key findings: i) improved correlation between clumps and spiral arm loci, and the discovery of clumps beyond the outer arm supports the existence of a new spiral structure; ii) decreasing trend in the L/M-ratio consistent with less high-mass star formation in the outer Galaxy; iii) increase in the star formation fraction (SFF) in the outer Galaxy, suggesting that more clumps are forming stars despite their lower mass; iv) discrepancies in velocity assignments across different surveys that could affect ∼10 000 clumps, especially in the fourth quadrant.