Evidence for particle stability of 31F and particle instability of 25N and 28O

doi:10.1016/S0370-2693(99)00015-5

Physics Letters B

Volume 448, Issues 3–4, 25 February 1999, Pages 180-184

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Abstract

The neutron drip line up to fluorine has been investigated by the projectile fragmentation of a 94.1A MeV $^{40}$ Ar beam at the fragment separator RIPS at RIKEN. A new neutron-rich isotope, $^{31}$ F, has been observed for the first time while clear evidence for the particle instability of $^{24,25}$ N, $^{27,28}$ O and $^{30}$ F has been obtained. The sudden change in stability from oxygen to fluorine may demonstrate the onset of deformation for the neutron-rich fluorine isotopes.

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Acknowledgements

Our sincere gratitude is extended to the staff members of the RIKEN ring cyclotron for their operation of the ECR and accelerator. One of the authors (S.L.) gives thanks for support from RIKEN. The authors (S.L. and Y.P.) acknowledge partial support by the Russian Foundation for Fundamental Research (RFFI) under grand No. 96-02-17381a.

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Evidence for particle stability of 31F and particle instability of 25N and 28O

Abstract

Section snippets

Acknowledgements

Nucl. Phys. A

Nucl. Phys. A

Phys. Lett. B

Nucl. Phys.

At. Data Nucl. Data Tables

Phys. Lett. B

Nucl. Instrum. Methods B

Nucl. Instrum. Methods B

Phys. Rev. C

Evidence for particle stability of $^{31}$ F and particle instability of $^{25}$ N and $^{28}$ O