Eu151

Eu-151 is a stable isotope of the lanthanide element europium (Eu), having a mass number of 151 and atomic number 63. It is one of the two stable isotopes of europium, the other being Eu-153.

Natural occurrence and abundance: In natural europium, Eu-151 accounts for about 47.8% of the element, with Eu-153 making up the remainder. Europium is found in trace quantities in rare-earth minerals such as monazite and xenotime, and is typically separated during the refining of rare-earth oxides.

Nuclear properties: Eu-151 is stable and does not undergo radioactive decay under normal conditions. Its neutron number is 88 (since 151 − 63 = 88). As a stable isotope, it does not contribute to radiogenic activity.

Production and isolation: Because Eu-151 is a natural part of europium, it is obtained wherever europium is mined and processed. Isotopic separation or enrichment of Eu-151 versus Eu-153 is technically feasible with mass spectrometry or other separation techniques, but is not generally required for common industrial uses.

Applications and relevance: Stable isotopes of europium, including Eu-151, are used as tracers and calibration materials in isotopic analyses, such as isotope dilution mass spectrometry and geochemical studies. Europium as an element is widely used in phosphors for red and blue emissions in lighting and display technologies; the presence and ratios of stable europium isotopes, including Eu-151, are of interest in materials research and environmental investigations.

See also: Isotopes of europium.