pedrone
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- Mar 31, 2011
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Without checking the literature to be certain that this is the case here, there exist a certain kind of experiment that measure the half-lives of very short-lived excited states. These lifetimes can tell us about structure of the state. Unfortunately, the results it it give are always ambiguous since, while they can tell us whether the nucleus is very deformed or not, they cannot tell us in which way they are deformed. Are they prolate deformed (rugby ball shaped) or oblate deformed (sort of flying saucer shaped). So from this information one can deduce that the nucleus either has a prolate deformation (positive quadrupole moment) of some size or a oblate deformation (negative quadrupole moment) of another. However, to make a firm choice one must do a further experiment that firmly determines the sign of the quadrupole moment. This is usually done using "Coulomb excitation".
OK,
Tubbythin,
then please explain to us this:
Finally, compare:
1) 8O18:
-0.036(9) .....CER,R
2) 3Li7:
-0.0400(6) ......CER
-0.0400(3) ......CER
They have always the same value of the electric quadrupole moment.
How is it possible?
- The 8O18 has a structure with 18 nucleons with NO unpaired neutron
- The 3Li7 which has a structure with only 7 nucleons, and one neutron is unpaired
How can they have always the same quadrupole moment ????
!