Reexamining Black-Body Shifts for Hydrogenlike Ions

Understand

We investigate black-body induced energy shifts for low-lying levels of atomic systems, with a special emphasis on transitions used in current and planned high-precision experiments on atomic hydrogen and ionized helium.

• Fine-structure and Lamb-shift induced black-body shifts are found to increase with the square of the nuclear charge number, whereas black-body shifts due to virtual transitions decrease with increasing nuclear charge as the fourth power of the nuclear charge.
• We also investigate the decay width acquired by the ground state of atomic hydrogen, due to interaction with black-body photons.
• The corresponding width is due to an instability against excitation to higher excited atomic levels, and due to black-body induced ionization.