OPTICAL SPECTROSCOPY

Responsible: PhD. Jorge Reyna Almandos

Participants:
- PhD. Fausto Bredice
- PhD. Mónica Ranieri

Research topics

  • Atomic and Molecular Physics. Optical spectroscopy of ionized elements.
  • Spectral analysis of ionized noble gases: determination of characteristic atomic parameters, using various spectral sources, semi-empirical methods and theoretical calculations of the atomic structure Hartree Fock Relativistic (HFR) and Multiconfigurational Dirac Fock (MCDF).
  • Spatial and temporal analysis of plasmas produced by laser.
  • Technological applications of Optical Spectroscopy. Pollution studies using optical techniques.

Since the creation of the CIOp in 1977, the group's first research in laser and spontaneous spectroscopy, led by Dr. Mario Gallardo, currently retired but who continues to collaborate, focused on the study of molecular nitrogen and noble gases. In the first case, the most relevant task was carried out using a pulsed N2 laser, cooled to liquid air temperature. This allowed the temporal and frequency study of its bands in the UV and NIR. On the other hand, xenon gas as an active medium was used as a stimulated emission generator in the blue-green zone, and the same light source but without the cavity mirrors, in order to obtain very rich spontaneous spectra of Xe ions. in spectral lines. Since 1984, there has been a spectrograph to work in the vacuum ultraviolet zone of the electromagnetic spectrum, which was donated by the University of Lund, Sweden, with which a strong scientific relationship has been maintained in atomic spectroscopy. This instrument allowed us to begin the study of ionized noble gases in the VUV region. In addition to this instrument, there are spectrographs that cover the UV-VIS-IR region of the electromagnetic spectrum.

Currently, the spectral analysis of noble gas ions of interest in astrophysical studies, in high-temperature plasmas and in the excitation mechanisms of gaseous lasers is continuing. These works are carried out using experimental data obtained in our laboratory, in spectra of Ne, Ar, Kr and Xe from one to eight times ionized. This task is complemented by obtaining characteristic atomic parameters through the use of relativistic Hartree-Fock type calculations and diagonalization of energy matrices, which include interaction of configurations. The data on the studies of noble gases produced in our Group are reported by NIST, USA, (http://physics.nist.gov/PhysRefData/ASD/index.html).

Recently another type of technique called LIBS (Laser Induced Breakdown Spectroscopy) was incorporated into our group. This method involves high-power lasers that are focused on a solid or gaseous target, producing an ionized plasma. These spectra are recorded by a monochromator with an ICCD camera which allows the temporal evolution of the spectral lines to be recorded.

All the tasks briefly described gave rise to a dozen doctoral theses and a significant number of graduation theses. Likewise, close institutional and labor relations are maintained with other groups that work on similar issues in our country and abroad, especially with the Universities of Tandil, Rosario and Mar del Plata, Argentina, and the Universities of Lund, Sweden, the University of Campinas (UNICAMP), the Federal Fluminense University (UFF), the Federal University of Roraima (UFRR), Brazil, the Universidad del Atlántico, Colombia, the National Autonomous University of Mexico, and the Istituto per i Processi Chimico-Fisici (IPCF) CNR, Pisa, Italy.

 

Lines of research:

Projects in progress: