68Xe

68Xe is a xenon isotope with mass number 68. It would have 54 protons and 14 neutrons, placing it extremely proton-rich relative to the known stable Xenon isotopes. Current mass evaluations and drip-line predictions place 68Xe beyond the proton drip line, and there is no confirmed bound state or experimental decay data for this nuclide.

Production and decay of 68Xe have not been observed in laboratory experiments. If it could be produced in high-energy nuclear reactions, 68Xe would be expected to be extremely short-lived, decaying on a rapid timescale through proton emission and possibly beta-plus decay sequences to lighter, more stable nuclei. The exact lifetimes and dominant decay pathways are not established and are subject to theoretical modeling.

The isotope remains of interest primarily to nuclear theory, serving as a data point for models of the proton-rich edge of the nuclear landscape and for tests of mass formulas and drip-line predictions. The lack of experimental evidence means that the characteristics of 68Xe—such as binding energy and decay channels—are inferred from theoretical considerations rather than measured data.

See also: Proton drip line, Xenon isotopes, Nuclear binding energy, Rare isotope beams.