Production and characterization of hot nuclei in the reactions of 19 and 35 MeV/u 14N with 145Sm

doi:10.1016/0375-9474(88)90245-X

Nuclear Physics A

Volume 486, Issue 2, 12 September 1988, Pages 429-455

https://doi.org/10.1016/0375-9474(88)90245-X Get rights and content

Abstract

Hot nuclei produced in the reactions of 261 MeV and 490 MeV ¹⁴N with ¹⁵⁴Sm have been studied. The initial properties of these nuclei; excitation energies, angular momenta and temperatures, have been characterized through measurements of residue velocities, gamma ray multiplicities and α-particle energy spectra. Nuclei with excitation energies as high as 400 MeV and temperatures as high as 6 MeV are produced. Determinations of the variation of temperature with excitation energy for nuclei of $A ⋍ 160$ indicate that the apparent level density parameter a, defined as $E^{∗} |T^{2}$ changes from A/8 at low energies to ≈ A/13 at 400 MeV excitation energy. Effective particle emission barriers suggest large shape fluctuations during the de-excitation cascade. At 35 MeV/u the variation of angular momentum transfer with linear momentum transfer in incomplete fusion reactions is in reasonable agreement with values calculated using a geometric overlap model.

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⁴: Permanent Address, Institute of Physics, Jagiellonian University, PL 30059, Cracow, Poland.

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Production and characterization of hot nuclei in the reactions of 19 and 35 MeV/u 14N with 145Sm

Abstract

Nucl. Phys.

Phys. Lett.

Nucl. Phys.

Phys. Lett.

Phys. Rev. Lett.

Nucl. Phys.

Phys. Lett.

Nucl. Instr. Meth.

Nucl. Phys.

Phys. Rev.

Nucl. Data Sheets

Nucl. Phys.

Z. Phys.

Phys. Lett.

Computer code VULCAN

Computer code LISA

Nucl. Instr. Meth.

ORNL report ORNL/TM 7295

Nucl. Phys.

Nucl. Phys.

Z. Phys.

Phys. Rev.

J. de Phys.

Production and characterization of hot nuclei in the reactions of 19 and 35 MeV/u ¹⁴N with ¹⁴⁵Sm