CARS spectroscopy of the (v=0 → 1)band in T2

Abstract

Molecular hydrogen is a benchmark system for bound state quantum calculation and tests of quantum electrodynamical effects. While spectroscopic measurements on the stable species have progressively improved over the years, high-resolution studies on the radioactive isotopologues T2, HT and DT have been limited. Here we present an accurate determination of T2 Q(J = 0-5) transition energies in the fundamental vibrational band of the ground electronic state, by means of high-resolution coherent anti-Stokes Raman spectroscopy. With the present experimental uncertainty of 0.02 cm-1, which is a fivefold improvement over previous measurements, agreement with the latest theoretical calculations is demonstrated.