Eur. Phys. J. D 53, 147-151 (2009)
https://doi.org/10.1140/epjd/e2009-00125-6

Two-step laser excitation of the highly excited even-parity states of atomic mercury

¹ National Institute of Laser & Optronics (NILOP), P.O. Box Nilore, 45650 Islamabad, Pakistan
² Department of Electrical Engineering, COMSATS Institute of Information Technology, Islamabad Campus, Pakistan
³ Alomic and molecular Physics Laboratory, Department of Physics, Quaid-i-Azam University, 45320 Islamabad, Pakistan

Corresponding author: ^a drali_nadeem@yahoo.com

Received: 1 December 2008
Revised: 17 February 2009
Published online: 17 April 2009

Abstract

We report term energies and quantum defects of highly excited even-parity states of mercury in the 83 876–84 140 cm^-1 energy range, employing a two-step laser excitation scheme via the S₀↦6s6p³P₁ inter-combination transition. Two dye lasers, pumped by a common Nd:YAG laser, were frequency doubled by BBO crystals and used to record the spectra in conjunction with a thermionic diode ion detector. Our new observations include the much extended D₂ (22 ≤n ≤52) series and a few members of the S₁ (24 ≤n ≤30) Rydberg series. Members of the D₂ Rydberg series with such a high n value are reported for the first time. The relative intensities of the D₂ and S₁ transitions (m = 4, 5 and 6) of group II-B elements excited from the P₁ inter-combination states are also discussed.