This proposal combines state-of-the-art laboratory atomic spectroscopy and laser physics to provide a new and better understanding of infrared astrophysical objects. The aim of the research is to use radiative lifetimes in combination with branching fractions (BF) to obtain oscillator strengths for atomic transition lines. Specific 'tracer' lines will be used to determine, often for the first time, accurate effective temperature, metallicity, and surface gravity, for IR stellar objects including Sub Solar Objects (SSO). The spectral opacity of SSOs peak in the IR where their spectra is dominated by neutral atoms and molecules. It is proposed that atomic data should be used to determine the atmospheric parameters. However, the current atomic database for the IR lacks oscillator strengths for the majority of elements required for the analysis of SSOs. The project will focus on the measurement of: 1. Wavelengths, line broadening and BFs, using the new high resolution IR Fourier transform spectrometer (FTS) at the Atomic Astrophysics group, Lund Observatory. 2. Radiative lifetimes, determined by time resolved laser induced fluorescence (TR LIF) at the Lund Laser Centre (LLC). The analysis of the SSO spectra will be carried out in collaboration with H.R.A. Jones (Centre for Astrophysics Research, University of Hertfordshire). Training: High resolution IR FTS: The researcher’s previous experience in UV FTS will be enhanced by instruction in IR FTS and general laboratory techniques for IR spectroscopy, an experimentally demanding region for observations. TR LIF: The LLC is a world leader in radiative lifetime measurement using TR LIF. The candidate will be instructed in the operation of the TR LIF system, including laser/optical alignment, source preparation and data reduction. The training will significantly enhance the candidate’s experimental skills and provide him with a firm base from which he can build an independent career.