Complex fragment production and multifragmentation in 139La-induced reactions at 35, 40, 45 and 55 MeV/u

doi:10.1016/0375-9474(93)90460-F

Nuclear Physics A

Volume 551, Issue 3, 18 January 1993, Pages 508-540

https://doi.org/10.1016/0375-9474(93)90460-F Get rights and content

Abstract

Complex fragment emission (Z>3) has been studied in the reactions of 35, 40, 45 and 55 MeV/u¹³⁹La+X. Charge, angular, and energy distributions were measured inclusively and in coincidence with other complex fragments, and were used to extract source rapidities, velocity distributions, and cross sectins. Multifragment events increase with both bombarding energy and entrance-channel mass asymmetry. The excitation functions for multifragment events rise strongly with excitation energy. These excitation functions are independent of the target-projectile combination and bombarding energy suggesting, the formation of an intermediate nuclear system, whose decay properties depend mainly on its excitation energy and angular momentum.

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¹: On leave from the SEPN, Centre d'Etudes Nucléaires Saclay, 91191 Gif-sur-Yvette, Cedex, France

²: Present address: GANIL BP 5027 F14021 CAEN, France.

³: On leave from the Institut de Physique Nucléaire, 91406 Orsay, Cedex, France

⁴: Present address: University of Maryland, College Park, MD 20247, USA

⁵: Present address: Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA.

⁶: On leave from the Institute of Atomic Energy, Beijing, China

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Nuclear Physics A

Abstract

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Reducibility and thermal scaling in nuclear multifragmentation

Exclusive multidetection and study of projectile breakup at 25 and 35A MeV in <sup>24</sup>Mg + <sup>197</sup>Au

Evidence for the reducibility of multifragment emission to an elementary binary emission in Xe-induced reactions

Fragment emission pattern in central and semi-central heavy-ion collisions

Breakup of highly excited <sup>35</sup>Cl projectiles on a gold target at 30 A MeV: An exclusive analysis

Angular and velocity analysis of the three-fold events in the Xe + Cu reaction at 45 MeV/u