"Safe" Coulomb Excitation of 30Mg

Phys. Rev. Lett.

94
172501
(2005)
. Niedermaier, H. Scheit, V. Bildstein, H. Boie, J. Fitting, R. von Hahn, F. Köck, M. Lauer, U. K. Pal, H. Podlech, R. Repnow, D. Schwalm, C. Alvarez, F. Ames, G. Bollen, S. Emhofer, D. Habs, O. Kester, R. Lutter, K. Rudolph, M. Pasini, P. G. Thirolf, B. H. Wolf, J. Eberth, G. Gersch, H. Hess, P. Reiter, O. Thelen, N. Warr, D. Weisshaar, F. Aksouh, P. Van den Bergh, P. Van Duppen, M. Huyse, O. Ivanov, P. Mayet, J. Van de Walle, J. Äystö, P. A. Butler, J. Cederkäll, P. Delahaye, H. O. U. Fynbo, L. M. Fraile, O. Forstner, S. Franchoo, U. Köster, T. Nilsson, M. Oinonen, T. Sieber, F. Wenander, M. Pantea, A. Richter, G. Schrieder, H. Simon, T. Behrens, R. Gernhäuser, T. Kröll, R. Krücken, M. Münch, T. Davinson, J. Gerl, G. Huber, A. Hurst, J. Iwanicki, B. Jonson, P. Lieb, L. Liljeby, A. Schempp, A. Scherillo, P. Schmidt, G. Walter

We report on the first radioactive beam experiment performed at the recently commissioned REX-ISOLDE facility at CERN in conjunction with the highly efficient 𝛾 spectrometer MINIBALL. Using  
30
 Mg 
  ions accelerated to an energy of 2.25  MeV/𝑢 together with a thin  
nat
 Ni 
  target, Coulomb excitation of the first excited 2+ states of the projectile and target nuclei well below the Coulomb barrier was observed. From the measured relative deexcitation 𝛾-ray yields the 𝐵⁡(𝐸⁢2;0+
gs →2+
1) value of  
30
 Mg 
  was determined to be 241⁢(31)⁢𝑒2   fm4. Our result is lower than values obtained at projectile fragmentation facilities using the intermediate-energy Coulomb excitation method, and confirms the theoretical conjecture that the neutron-rich magnesium isotope  
30
 Mg 
  resides outside the “island of inversion.”

DOI
10.1103/PhysRevLett.94.172501
Published on
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