Dysprosium isotope

M. K. DRAKE and O. M. MATHEWS, "Cross Section Compilation for the Major Gadolinium, Hafnium and Dysprosium Isotopes," GAMD (to be issued). General Atomic. 

ISOTOPES There are a total of 39 isotopes of dysprosium, seven of which are stable. The atomic mass of the stable isotopes ranges from 156 to 164 amu (atomic mass units or atomic weight). The unstable isotopes of dysprosium have half-lives ranging from 150 milliseconds to 3.0x10+ years. All of the unstable Isotopes are radioactive and are produced artificially. 

Californium is a transuranic element of the actinide series that is homologous with dysprosium (gjDy), just above it in the rare-earth lanthanide series. Cf-245 was the first isotope of californium that was artificially produced. It has a half-life of just 44 minutes. Isotopes of californium are made by subjecting berkelium to high-energy neutrons within nuclear reactors, as follows + (neutrons and A, gamma rays) — °Bk — °Cf + (3- (beta particle... 

For example, the isotopic composition and the atomic weight of neodyminm," dysprosium and erbium have been determined using synthetic mixtnres prepared gravimetrically from highly enriched isotopes of neodymium in the form of oxides of weU defined pnrity by TIMS. No natnral isotopic variation was found in terrestrial neodymium, dysprosium or erbium samples. These isotopic compositions of Dy and Er measnred by TIMS are accepted as the best measurements from a single terrestrial source as noted in the table of isotopic composition of elements, 2001. °... 

Seven naturally occurring isotopes of dysprosium are known. Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the right of the element s name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. The four most abundant isotopes of dysprosium are dysprosium-161, dysprosium-162, dysprosium-163, and dysprosium-164. 

Twenty-eight radioactive isotopes of dysprosium have been made. A radioactive isotope is one that is unstable, gives off radiation, and breaks down to form a new isotope. Of these isotopes, only one, dysprosium-166, has much commercial importance. It is used to treat certain types of cancer, to relieve pain due to cancer, and in the treatment of joint problems. 

The radioactive isotope dysprosium-165 is also being studied for some potential applications in medicine. Radiation with dysprosium-165... 

Figure 12. Isotope structure of the 5887.9-A line of neodymium (a) and the 5988.6-A line of dysprosium (b). The abscissa in each figure is relative frequency in gigahertz (11).

Figure 13. Structure of the 5988.562-A line of neutral dysprosium. Three of the lines—4,10 and 17—are due to even isotopes (no hfs), the remainder are hfs components from the odd 1 = 5/2 isotopes, dysprosium-161 and dysprosium-163. The key at the top gives the values for F(J = 8)...

Dysprosium has 7 stable isotopes. There are 29 radioisotopes with the most stable being " Dy with a half-life of 3.0 million years, Dy with a half-life of 144.4 days, and Dy with a half-life of 81.6 h. All other radioactive isotopes have half-lives that are less than 10 h (Table 3.9). 

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