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Recent studies have uncovered a rare population of supermassive (M ★ ≳ 10 11 M ⊙ ), yet actively star-forming spiral galaxies – super spiral galaxies (SSGs) – whose existence challenges classical mass- and environment-quenching scenarios. We investigate the resolved star-forming and molecular-gas properties of the nearby SSG UGC 8179 ( z = 0.052, log(M ★ /M ⊙ ) = 11.62) in order to assess whether its local star formation (SF) follows the same physical processes as those observed in typical star-forming main-sequence (SFMS) spirals. We combined the first spatially resolved CO(1–0) interferometric observations of an SSG with pixel-by-pixel SED fitting, based on archival UV–to–mid-IR imaging. Our 3″ × 3″ (∼25 kpc 2 ) pixel maps provide spatially resolved measurements of stellar mass, star formation rate (SFR), and molecular gas surface densities across its extended disk. UGC 8179 hosts a massive rotating molecular gas reservoir of M H2 = 1.02 × 10 10 M ⊙ , yielding a standard molecular gas fraction and a typical depletion time of ∼1 Gyr in the region observed by NOEMA, despite its extreme mass. We derive lower limits of log 10 f mol ≥ −1.61 ± 0.06 and log 10 τ dep ≥ 8.82 ± 0.13 at the scale of the galaxy. The large spatial extent of UGC 8179 enables us to probe low surface-density regimes hardly accessible in nearby disks (Σ ★ < 10 7 M ⊙ kpc −2 ; Σ SFR < 10 −3.5 M ⊙ yr −1 kpc −2 ). All three resolved scaling relations (resolved SFMS – rSFMS, resolved Kennicutt Schmidt – rKS, and resolved molecular gas main sequence – rMGMS) are well defined. The rKS slope (0.87 ± 0.09) is broadly consistent with unity, indicating standard local SF processes. The rSFMS shows a shallower global slope (0.80 ± 0.02) due to a central suppression in specific SFR (∼ − 0.5 dex), but a two-component fit restores agreement with literature relations at Σ ★ ≲ 10 7.2 M ⊙ kpc −2 . This break suggests the influence of a bulge – and possibly a bar – driving a transition to a more dynamically regulated SF regime in the inner disk. A similar flattening in the rMGMS supports this interpretation. UGC 8179 provides evidence that SSGs can sustain standard local SF processes while exhibiting central dynamical regulation at high stellar surface densities. Extending this analysis to our full sample of 19 SSGs and nearby massive unquenched spirals will enable us to test whether such regulation is a common feature among massive unquenched spirals.
Cologni et al. (Wed,) studied this question.