Bar formation in submaximal discs: a challenge for ?CDM

ABSTRACT Bar formation in cosmological simulations of galaxy remains challenging. It was previously shown that the fraction barred galaxies at low stellar masses (M* < 1010.5 M?) TNG50 is too compared to observations. Here, we highlight another tension, also observed higher masses, namely appear be maximal discs, sense majority gravitational acceleration accounted for by baryons peak radius baryonic rotation curve, while observations account a substantial submaximal discs. In this letter, compare discs local Universe from SPARC catalogue with simulation. We show that, although tends select against galaxies, data set significantly larger than TNG50. This result adds list challenges related predicting right statistics and properties ?CDM formation.