Recent experiments at Brookhaven: level structure of N=86 isotones 156Yb and 150Gd

States of the N=86 isotones 156Yb and 150Gd have been studied by means of the 144Sm(16O, 4n)156Yb, 113In(46Ti, p2n)156Yb and the 124Sn(30Si, 4n)150Gd reactions. Levels have been established to spin 36(h/2π) and over 12.5 MeV in excitation in 150Gd and to beyond spin 25(h/2π) in 156Yb. The systematics of levels in the N=86 isotones from 150Gd to 156Yb are described, and the near-spherical shell model description for states in this region to near spin 30(h/2π) is discussed. A Tsub(1/2)=6 ns, 72 keV isomeric transition in 156Yb has been discovered, and an E1 multipolarity is assigned to this transition. The spin-parity of the isomeric state is established as 11-. (Auth.)