Summary of Research Project Results under JSPS FY2002
"Research for the Future Program"



1.Research Institution Kobe University
2.Research Area Physical and Engineering Science
3.Research Field Photoscience
4.Term of Project FY 1998 - FY 2002
5.Project Number 98P01201
6.Title of Project Development and Application of High Performance Lasers and Spectrometers

7.Project Leader
Name Institution,Department Title of Position
Hajime, Katô Kobe University, Molecular Photoscience Research Center Professor

8.Core Members

Name Institution,Department Title of Position
Masaaki, Baba Kyoto University, Faculty of Integrated Human Studies Associate Professor
Keisuke, Tominaga Kobe University, Molecular Photoscience Research Center Professor
Kiyokazu, Fuke Kobe University, Faculty of Science Professor

9.Summary of Research Results

1. Construction of a single-mode tunable laser system to use high resolution molecular spectroscopy.
  A part of the output beam of a single-mode tunable laser was passed through a temperature stabilized etalon, and jitters of the wave number were reduced by using the error signal. The laser could scan 25 GHz while maintaining the line width of less than 1 MHz/s. The wavelength of a cw Nd:YAG laser was locked to a hyperfine line of iodine molecule I2. The length of reference cavity was locked to the wavelength of the cw Nd:YAG laser. A fraction of the scanning laser beam was introduced into the reference cavity, and transmission peaks with an interval of every 30.0 MHz were marked. Another fraction was used to measure the Doppler-free absorption spectrum of I2. These are used to calibrate the wave number of scanning laser beam.
2. Publication of Doppler-Free High Resolution Spectral Atlas of Iodine Molecule 15000-19000 cm-1.
  The Doppler-free absorption spectrum of I2 has been measured, and the data were published as "Doppler-Free High Resolution Spectral Atlas of Iodine Molecule 15000-19000 cm-1" by JSPS (ISBN 4-89114-000-3). Using attached CDROM, the absolute wave numbers of all the hyperfine components can be obtained. This can be used to calibrate the absolute wave number of molecular transition lines with accuracy of approximately 0.0001 cm-1.
3. Opening of a new field to explore the structure and dynamics of many polyatomic molecules.
  A variety of techniques of Doppler-free high resolution spectroscopies, namely DFLP, DFOOPL, DFTPA, and excitation spectrum measured by crossing laser and molecular beams, have been developed. Rotationally resolved spectra up to naphthalene molecule were measured by these techniques. DFTPA spectrum of glyoxal was measured and assigned with accuracy better than 0.00003 cm-1, which is the world record in resolution and accuracy of an electronic spectra of polyatomic molecules. For the first time DFLP and DFOOPL spectroscopy is successfully applied to a large polyatomic molecule. It was demonstrated that we can measure the Zeeman effects for many polyatomic molecules in a singlet state. It is promising to extend the applicability of high resolution spectroscopy and to open a new field to explore the structure and dynamics of many polyatomic molecules.

10.Key Words
(1)Laser   (2)High resolution   (3)Spectroscopy
(4)Doppler-free   (5)Iodine   (6)Spectrum
(7)Magnetic field   (8)Measurement   (9)Molecule

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