The time delay in fission induced by bombardment of W with 180 MeV 32S, 240–255 MeV 48Ti, and 315–375 MeV 58Ni has been measured by observation of crystal blocking. There is a clear narrowing and a small increase in the minimum yield of the angular dips for fission compared with scaled dips for elastically scattered ions. This is interpreted as a fission delay of about 2 as, only weakly dependent on energy and atomic number. The delay is longer by 1 to 2 orders of magnitude than obtained from standard interpretations of measurements of prescission neutrons and giant-dipole-resonance gamma rays and from calculations of the nuclear dynamics in heavy-ion reactions.
J.U.Andersen, J.Chevallier, J.S.Forster, S.A.Karamian, C.R.Vane, J.R.Beene, et al. (2007). Crystal blocking measurements of the time delay of fission induced by S, Ti and Ni borbardment of W. PHYSICAL REVIEW LETTERS, 99, 162502-1-162502-4 [10.1103/PhysRevLett.99.162502].
Crystal blocking measurements of the time delay of fission induced by S, Ti and Ni borbardment of W
MALAGUTI, FRANCO;UGUZZONI, ARNALDO
2007
Abstract
The time delay in fission induced by bombardment of W with 180 MeV 32S, 240–255 MeV 48Ti, and 315–375 MeV 58Ni has been measured by observation of crystal blocking. There is a clear narrowing and a small increase in the minimum yield of the angular dips for fission compared with scaled dips for elastically scattered ions. This is interpreted as a fission delay of about 2 as, only weakly dependent on energy and atomic number. The delay is longer by 1 to 2 orders of magnitude than obtained from standard interpretations of measurements of prescission neutrons and giant-dipole-resonance gamma rays and from calculations of the nuclear dynamics in heavy-ion reactions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
