Direct measurement of the masses of li11 and Na26-32 with an on-line mass spectrometer

Abstract

The use of an on-line mass spectrometer to make direct mass measurements of short-lived isotopes far from the stability line has been improved to yield more accurate mass measurements for Na27-30, new mass measurements for Li11, Na31,32, and to remove a discrepancy between existing mass measurements of Na26. The mass excesses (keV) measured are: Li11, 40940±80; Na26, -6901±25; Na27, -5620±60; Na28, -1140±80; Na29, 2650±100; Na30, 8370±200; Na31, 10600±800; Na32, 16400±1100. The Li11 value indicates that it is bound by only 170±80 keV. The masses of Na31 and Na32 imply that these nuclei are more tightly bound than expected from theoretical predictions. NUCLEAR STRUCTURE Li11, Na26-32; measured atomic masses. On-line mass spectrometer. RADIOACTIVITY Li11; deduced logft. © 1975 The American Physical Society.