Book contents
- Frontmatter
- Contents
- Preface
- Part One Content description
- A Aluminum Al to Arsenic As
- B Barium Ba to Boron B
- C Cadmium Cd to Curium Cm
- D Dysprosium Dy
- E Erbium Er to Europium Eu
- F Fluorine F
- G Gadolinium Gd to Gold Au
- H Hafnium Hf to Hydrogen H
- I Indium In to Iron Fe
- K Krypton Kr
- L Lanthanum La to Lutetium Lu
- M Magnesium Mg to Molybdenum Mo
- N Neodymium Nd to Nitrogen N
- O Osmium Os to Oxygen O
- P Palladium Pd to Promethium Pm
- R Rhenium Re to Ruthenium Ru
- S Samarium Sm to Sulfur S
- T Tantalum Ta to Tungsten W
- U Uranium U
- V Vanadium V
- X Xenon Xe
- Y Ytterbium Yb to Yttrium Y
- Z Zinc Zn to Zirconium Zr
- Summary
- Part Two Content description
- Part Three Content description
- Part Four Content description
- References
- Index of elements in stars
- Index of molecules in stars
E - Erbium Er to Europium Eu
Published online by Cambridge University Press: 06 July 2010
- Frontmatter
- Contents
- Preface
- Part One Content description
- A Aluminum Al to Arsenic As
- B Barium Ba to Boron B
- C Cadmium Cd to Curium Cm
- D Dysprosium Dy
- E Erbium Er to Europium Eu
- F Fluorine F
- G Gadolinium Gd to Gold Au
- H Hafnium Hf to Hydrogen H
- I Indium In to Iron Fe
- K Krypton Kr
- L Lanthanum La to Lutetium Lu
- M Magnesium Mg to Molybdenum Mo
- N Neodymium Nd to Nitrogen N
- O Osmium Os to Oxygen O
- P Palladium Pd to Promethium Pm
- R Rhenium Re to Ruthenium Ru
- S Samarium Sm to Sulfur S
- T Tantalum Ta to Tungsten W
- U Uranium U
- V Vanadium V
- X Xenon Xe
- Y Ytterbium Yb to Yttrium Y
- Z Zinc Zn to Zirconium Zr
- Summary
- Part Two Content description
- Part Three Content description
- Part Four Content description
- References
- Index of elements in stars
- Index of molecules in stars
Summary
This element was discovered by C. Mossander in Stockholm in 1842. The name comes from the city of Ytterby in Sweden. This city is also referred to in the names of the elements yttrium and terbium.
lonization energies
ErI 6.1 eV, ErII 11.9 eV, ErIII 22.7 eV, ErIV 42.6 eV.
Absorption lines of ErII and ErIII
ErII 3616 is seen in one FOIb star (W=0.015) according to Reynolds et al (1988).
Behavior in non-normal stars
ErII lines are strengthened in the spectra of some Ap stars of the Cr-Eu-Sr subgroup. Aikman et al. (1979) also observed ErIII in the spectra of stars with strong ErII lines, and this was confirmed by Cowley and Greenberg (1987). The ErIII line at 4000 has W= 0.040. ErII and ErIII lines were also detected in the spectrum of one Bp star of the Si subgroup (Cowley and Crosswhite 1978).
ErII lines are also seen in at least one Am star (van t'Veer-Menneret etal 1988) with W[4009)=0052.
ErII lines are enhanced in at least one Ba star (Lambert 1985) and in at least one S-type star (Bidelman 1953).
Isotopes
Er has six stable isotopes and ten unstable isotopes and isomers. The stable ones are Er 162, 164, 166, 167, 168 and 170. In the solar system Er166 represents 33% and Er 167, 168 and 170 respectively 23%, 27% and 14%.
Origin
Er is made by several processes, Er162 by the p process, Er167 and Er170 by the r process and the others can be made by two processes, namely Er164 by the p or the s and Er166 and Er168 by either the r or the s process.
- Type
- Chapter
- Information
- The Behavior of Chemical Elements in Stars , pp. 57 - 59Publisher: Cambridge University PressPrint publication year: 1995