CARS spectroscopy of the ($v=0\to1$) band in $\rm{T_2}$

TL;DR

This study uses high-resolution CARS spectroscopy to precisely measure the vibrational transition energies of radioactive hydrogen isotope T₂, achieving significant accuracy improvements and confirming theoretical predictions.

Contribution

First high-resolution measurement of T₂ vibrational transitions with fivefold improved accuracy, validating quantum calculations for radioactive hydrogen isotopologues.

Findings

Measured T₂ Q(J=0-5) transition energies with 0.02 cm⁻¹ uncertainty.

Achieved fivefold improvement over previous experimental data.

Confirmed agreement between experimental results and theoretical calculations.

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 $\rm{T_2}$, $\rm{HT}$ and $\rm{DT}$ have been limited. Here we present an accurate determination of $\rm{T_2}$ $Q(J = 0 - 5)$ 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 $0.02\,\rm{cm^{-1}}$, which is a fivefold improvement over previous measurements, agreement with the latest theoretical calculations is demonstrated.