R.Kanungo1, M.Chiba1, N.Iwasa2, S.Nishimura1, A.Ozawa1, C.Samanta3,4, T.Suda1, T.Suzuki5, T.Yamaguchi1, T.Zheng1, I.Tanihata1 Inst.of Physical and Chemical Res. (RIKEN1 Tohoku Univ., Sendai2 United States of America3 Saha Institute, Kolkata4 Niigata Univ., Niigata5
Physical Review Letters88(2002)142502