Attosecond time delays in heavy-ion induced fission measured by crystal blocking

被引：35

作者：

Andersen, J. U. ^{[1
]}

Chevallier, J. ^{[1
]}

Forster, J. S. ^{[2
]}

Karamian, S. A. ^{[3
]}

Vane, C. R. ^{[4
]}

Beene, J. R. ^{[4
]}

Galindo-Uribarri, A. ^{[4
]}

del Campo, J. Gomez ^{[4
]}

Gross, C. J. ^{[4
]}

Krause, H. F. ^{[4
]}

Padilla-Rodal, E. ^{[4
]}

Radford, D. ^{[4
]}

Shapira, D. ^{[4
]}

Broude, C. ^{[5
]}

Malaguti, F. ^{[6
,7
]}

Uguzzoni, A. ^{[6
,7
]}

机构：

[1] Univ Aarhus, Dept Phys, DK-8000 Aarhus C, Denmark

[2] Univ Montreal, Dept Phys, Montreal, PQ H3C 3J7, Canada

[3] Joint Inst Nucl Res, FLNR, RU-141980 Dubna, Russia

[4] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA

[5] Weizmann Inst Sci, Dept Phys, IL-76100 Rehovot, Israel

[6] Univ Bologna, Dept Phys, I-40126 Bologna, Italy

[7] Ist Nazl Fis Nucl, I-40126 Bologna, Italy

来源：

PHYSICAL REVIEW C | 2008年 / 78卷 / 06期

关键词：

D O I：

10.1103/PhysRevC.78.064609

中图分类号：

O57 [原子核物理学、高能物理学];

学科分类号：

070202 ;

摘要：

The time delays in fission induced by bombardment of W with 180 MeV S-32, 240-255 MeV Ti-48, 330-375 MeV Ni-58, and 390 MeV Ge-74 have been measured by observation of crystal blocking. Nearly all results are consistent with exponential decay with lifetimes of order 10(-18) s which depend weakly on the atomic number of the composite nucleus. This is inconsistent with the Bohr-Wheeler model of fission from a compound nucleus in statistical equilibrium at each stage in a neutron evaporation cascade and supports a picture of strongly damped quasifission. A simple diffusion model with one-body dissipation reproduces roughly the observed time scale and the exponential decay. It suggests that the outer fission barrier could play a significant role in the observed, very slow decays.

引用

页数：17

共 47 条

[1] Crystal blocking measurements of the time delay of fission induced by 32S, 48Ti, and 58Ni bombardment of W [J].