Magnetic dipole line from U lxxi ground-term levels predicted at 3200 Å

Magnetic dipole (M1) lines above 2500 Å are convenient diagnostic tools for high-energy, low-density plasmas such as those of tokamaks. We found a sequence of such lines arising from transitions between two levels of the 3d4 5D ground term of titaniumlike ions. From Nd xxxix to U lxxi the calculated wavelengths range from 3557 to 3200 Å with ionization energies of 2.7 to 8.2 keV. These lines have transition rates of 480 to 262 sec−1. The calculations were made with the multiconfiguration Dirac–Fock code of Desclaux [ J. Phys. B20, 651 ( 1987)].