Interference of two signals with different origin:


1.     Deep interior   ωqq=190 MeV
   
2.     Surface   ωglue=????


Solutions for surface oscillations:

1.   ωglue = 190+2×76 = 324 MeV   → lattice
   
2.   ωglue = 190-2×76 = 38 MeV   → giant resonances