Moderate color superconductivity and the thermal-twin constraint

Determine whether hybrid equation-of-state models with moderate diquark pairing can fulfill the thermal-twin constraint associated with core-collapse supernova explodability.

Background

The paper finds that strong color superconductivity prevents the formation of thermal twin-star branches in the studied confining density functional model. Because the authors propose thermal twins as an indicator of the explodability of massive progenitor stars, this result disfavors strong pairing and leaves unresolved whether weaker or moderate diquark pairing could satisfy the proposed thermal-twin requirement while retaining physically viable quark matter.

The unresolved issue concerns the parameter regime and possible medium dependence of the diquark interaction. Establishing whether moderate pairing can simultaneously produce suitable phase-transition properties, massive neutron stars, and thermal twins would test the robustness of the proposed constraint on dense-matter equations of state.

References

By this argument, strong color superconductivity shall be excluded and it remains to be shown whether models with moderate diquark pairing could fulfill the thermal twin constraint.

— Confining density functional approach to the QCD phase diagram at low temperatures and thermal twin stars  (2608.18038 - Blaschke et al., 18 Aug 2026) in Abstract

But even in a crossover-type situation it is not excluded that thermal twin stars would emerge which according to the bold conjecture of this work, may be indicators of the CCSN explodability of the corresponding EoS, as required by astronomical observations.

— Confining density functional approach to the QCD phase diagram at low temperatures and thermal twin stars  (2608.18038 - Blaschke et al., 18 Aug 2026) in Section Conclusions and Outlook