Isotopes of gadolinium

The predicted double beta decay of 160Gd has never been observed; only a lower limit on its half-life of more than 1.3×1021 years has been set experimentally.

It is used as a gamma ray source for X-ray absorptiometry and fluorescence, for bone density gauges for osteoporosis screening, and for radiometric profiling in the Lixiscope portable x-ray imaging system, also known as the Lixi Profiler.

In nuclear medicine, it serves to calibrate the equipment needed like single-photon emission computed tomography systems (SPECT) to make x-rays.

It ensures that the machines work correctly to produce images of radioisotope distribution inside the patient.

[9] It can also detect the loss of calcium in the hip and back bones, allowing the ability to diagnose osteoporosis.