Establishment of M1 multipolarity of a 6.5 mu_N^2 resonance in 172-Yb at   E_gamma=3.3 MeV
  Two-step-cascade spectra in 172-Yb have been measured after thermal neutron capture. They are compared to calculations based on experimental values of the level density and radiative strength function (RSF) obtained from the 173-Yb(3-He,alpha gamma)172-Yb reaction. The multipolarity of a 6.5(15) mu_N^2 resonance at E_gamma=3.3(1) MeV in the RSF is determined to be M1 by this comparison. 
A. Schiller, A. Voinov, E. Algin, J.A. Becker, L.A. Bernstein, P.E.   Garrett, M. Guttormsen, R.O. Nelson, J. Rekstad, S. Siem