J. Phys. Colloques
Volume 49, Numéro C1, Mars 1988IAU Colloquium N° 102 on UV and X-ray Spectroscopy of Astrophysical and Laboratory Plasmas
|Page(s)||C1-127 - C1-127|
J. Phys. Colloques 49 (1988) C1-127-C1-127
THE CALCULATIONS FOR DETERMINATION OF THE AGE OF SUPERNOVA REMNANTS AND GALAXY CLUSTERS BY MEASUREMENTS OF HYPERFINE SPLITTING IN HIGHLY IONIZED ATOMS WITH UNSTABLE NUCLEII.M. BAND, M.A. LISTENGARTEN et M.B. TRZHASKOVSKAYA
Institute for Physics, St Peterhof, Leningrad State University, Leningrad 198904, USSR
The possibility of using the transitions between HFS components of atoms with nonstable nuclei in the spectra of hot gas in the supernova remnants and galaxy clusters for obtaining the information on the age of the objects was mentioned in / 1/ without calculations. Here we present the numerical results for some ionized atoms obtained by relastivistic Hartree-Fock-Dirac method. Fermi distribution of nuclear charge density, vacuum polarisation, electron anomalous magnetic moment and reduced mass were taken into account. The HFS energy levels can be written as ε = ( 1 /2)A(F(F+ 1)-J(J+ 1)-1(1+ 1)), where A=A'(µ/J). HFS constants A' in millielectronvolts for H- Li- and Na-like ions of unstable isotops with well known magnetic moments with Z < 53 are given in the table (abundance rapidly decreases with increasing of Z). For the s-electrons , wavelength λ = (hcJ)/(A'µ(J+( 1 /2))) ; J is the nuclear spin, hc = 1,23985.10-4eV.cmT1/2 is the halflife. Standard deviation is given in parentheses The influence of choice of parameters of nuclear charge and magnetisation distribution over the nuclear volume was also investigated.