1. Comb-Assisted Cavity Ring Down Spectroscopy
of 17O enriched water between 7443 and 7921 cm–1
D. Mondelain, S.N. Mikhailenko, E.V. Karlovets, S. Béguier, S. Kassi, and A. Campargue
Univ. Grenoble Alpes, CNRS France, Institute of Atmospheric Optics Tomsk Russia

2. 17O has S= 5/2 Isotopologue Abundance H216O 0.9973 H218O 2.0×10-3
3.7×10-4
HD16O
3.1×10-4
HD18O
6.23×10-7
HD17O
1.16×10-7
17O has S= 5/2

3. FTS literature
Toth RA. Transition frequencies and strengths of H217O and H218O: 6600 to 7640 cm−1. Appl Opt 1994;33: (L=2.39 m, 55% enrichment)

4. A compact CW-CRDS spectrometer
nm ( cm-1)
Photodiode
Optical isolator
Laser diode
Coupler AO
Modulator
laser ON
Laser OFF
-50 50
100
threshold
n=f(T,I)
6nm/diode
Wavemeter 4

5. Routine CRDS: ~ 100 laser diodes (6nm/diode)
nm ( cm-1)
t~ µs
Cell length : 1.4 m
volume : 150 cm3
Y scale
Sensitivity : 3x10-11 cm-1
Dynamic range ~
X scale
Scan speed : 30 cm-1 / hour
Spectral accuracy: ~ 1x10-3 cm-1

6. CRDS natural water
FTS literature

7. 17O enriched water (about 60%enrichment)

8. FTS literature

9. FTS literature

10. SRFC Wavemeter Coupler Photodiode Optical isolator Laser diode Coupler
+ ± 400 kHz-
Photodiode
Optical isolator
Laser diode
Coupler AO
Modulator
laser ON
Laser OFF
-50 50
100
threshold
n=f(T,I)
6nm/diode
Wavemeter
10 %
10 %
80 % 10

11. About 4150 lines (4670 transitions )
H216O, H217O, H218O, HD16O, HD17O, HD18O
Intensities from to cm/molecule

13. H217O
HD17O
Total: 398 transitions
(literature: 4)
207 new levels
Total: 1596 transitions
(literature:300)
329 new levels

14. Line position accuracy
Comparison to FS-CRDS referenced to a Cs clock by Sironneau and Hodges - JQSRT 152 (2015)1
71 H216O positions measured with an uncertainty of 3MHz (1x10-4 cm-1)
average difference= -0.2x10-4 cm-1
rms= 1.1x10-4 cm-1

15. Sub-kHz accuracy is achieved by Lamb dip spectroscopy
Optical feedback frequency stabilized cavity ring-down spectroscopy JCP 142 (2015)

18. I17O =5/2 -> electric quadrupole, 17O spin-rotation and…
I17O =5/2 -> electric quadrupole, 17O spin-rotation and….. I H+H= 1 terms (ortho transition )

19. FTS literature

20. Merci! 20