text: udQM could be possibly formed during a supernova core collapse from conversion of superheavy nuclei. In this environment there is a high density of electrons and electron neutrinos present. The udQM would then end up in neutron stars. udQM nuclides may be detectable in cosmic rays.
  A star containing a large proportion of udQM is called a ud quark star (or udQS). Heavy neutron stars may convert into this star type. Whether they do may be verified by detecting binary compact stellar collisions via gravitational waves.