New Isotopes:Li11,B

Abstract

Data obtained with semiconductor detectors and a particle-identifier system on fragments ejected from uranium bombarded with 5.3-GeV protons show that ^Li, 14 B, and 15 B are particle stable, 10 Li is particle unstable, and 13 Be is most probably particle unstable .

Study of 14Be with core excitation

“…That 13 Be is unbound was suggested more than 30 years ago [9,10], and confirmed in 1973 [11]. Although the detailed results and conclusions drawn from the available experiments are quite different, they do all agree that 13 Be has an excited state at approximately 2.0 MeV with spin-parity 5 2 + .…”

Elastic scattering and reactions of light exotic beams

“…This very neutron-rich isotope was discovered in 1966 at the Lawrence Radiation Laboratory [129]. Due to a rather short lifetime of about 8.6 ms, beams of 11 Li used in scattering experiments have thus far been produced by fragmentation of highenergy primary beams.…”

Selective population of unbound states in 10Li

“…The unbound nature of 10 Li was determined in 1966 by Poskanzer, Cosper, and Hyde [7]. Almost ten years later, Wilcox and collaborators made the first measurement of the unbound nucleus, using a ( 9 Be, 8 B) reaction to measure a mass excess of 33.83 ± 0.25 MeV [8].…”