Isomer energy level

Dear professors,
As the value of IS should be non-zero for isomer in usrrnc.f and following the discussions in Entire information for isotopes, I have two quick questions concerning the isomer energy level.

  1. Does the value of IS follow the order of energy? The higher the value is, the larger the energy is compared to the ground state?

  2. Does the isomer state correspond to the result in National Nuclear Data Center(NNDC)? Take the isomer of Sb124 for example, there are two isomers whose energy excess are 10.86keV and 36.84keV from NNDC. Therefore, a residual nuclei 51 124 1(2) should be Sb124(10.86keV)(Sb124(36.84keV)). Is that correct?

Thank you for your help!
Best regards,
Hechong Han

Dear Hechong Han

  1. Yes, that is always the case
  2. Ideally, that would be the case. However our isomer database dates back a few years. For well established isomers you can be confident that what we have is aligned with for example the NNDC listings. For more exotic nuclides with recently updated states, there might be a discrepency. In case you spot an inconsistency or obtain an array error, do not hesitate to report it here.


Dear @pschoofs
Thank you for your explanation!
Best regards,
Hechong Han