Appendix D
International Astronomical Union Spectral Lines of Most Importance Above 300 GHz
At each triennial meeting of the General Assembly, the International Astronomical Union (IAU) carefully reviews the list of astrophysically most important spectral lines that it maintains. The IAU expresses the need to protect these frequency bands from in-band, band-edge, and harmonic emissions, especially from spaceborne transmitters.
In preparation for World Radiocommunication Conference 2000, which revised the allocations above 71 GHz, a millimeter-wavelength working group of the Scientific Committee on Frequency Allocations for Radio Astronomy and Space Science examined all then-known transitions in the millimeter and submillimeter wavebands. The working group selected a limited number of the astrophysically most important spectral lines to supplement the earlier lists, such as those produced by the IAU, to be used in allocating frequency bands to the Radio Astronomy Service. Spectral lines above 300 GHz are listed in Table D.1. (These data and further information can be found on the Web site of the European Science Foundation’s Committee on Radio Astronomy Frequencies at http://www.astron.nl/craf/iaulist.htm.)
TABLE D.1 The Most Important Spectral Lines Between 275 and 1000 GHz
Substance |
Formula |
Frequency (GHz) |
Suggested Minimum Band (GHz) |
Diazenylium |
N2H+ |
279.511 |
279.23-279.79 |
Carbon monosulphide |
CS |
293.912 |
292.93-294.21 |
Hydronium |
H3O+ |
307.192 |
306.88-307.50 |
Deuterated water |
HDO |
313.750 |
313.44-314.06 |
Carbon monoxide |
C18O |
329.330 |
329.00-329.66 |
Carbon monoxide |
13CO |
330.587 |
329.49-330.92 |
Carbon monosulphide |
CS |
342.883 |
341.74-343.23 |
Carbon Monoxide |
CO |
345.796 |
345.45-346.14 |
Hydrogen cyanide |
HCN |
354.484 |
353.30-354.84 |
Formylium |
HCO+ |
356.734 |
355.54-357.09 |
Oxygen |
O2 |
368.498 |
368.13-368.87 |
Diazenylium |
N2H+ |
372.672 |
372.30-373.04 |
Water vapor |
H2O |
380.197 |
379.82-380.58 |
Hydronium |
H3O+ |
388.459 |
388.07-388.85 |
Carbon monosulphide |
CS |
391.847 |
390.54-392.24 |
Oxygen |
O2 |
424.763 |
424.34-425.19 |
Carbon monoxide |
C18O |
439.088 |
438.65-439.53 |
Carbon monoxide |
13CO |
440.765 |
439.30-441.21 |
Carbon monoxide |
CO |
461.041 |
459.50-461.50 |
Heavy water |
HDO |
464.925 |
464.46-465.39 |
Carbon |
CI |
492.162 |
490.52-492.65 |
Hydrogen cyanide |
HCN |
531.716 |
529.94-532.25 |
Carbon monosulphide |
CS |
538.689 |
536.89-539.23 |
Water vapor |
H218O |
547.676 |
547.13-548.22 |
Carbon monoxide |
13CO |
550.926 |
549.09-551.48 |
Water vapor |
H2O |
556.936 |
556.38-557.49 |
Ammonia |
15NH3 |
572.113 |
571.54-572.69 |
Ammonia |
NH3 |
572.498 |
571.93-573.07 |
Carbon monoxide |
CO |
576.268 |
574.35-576.84 |
Carbon monosulphide |
CS |
587.616 |
587.03-588.20 |
Deuterated water |
HDO |
599.927 |
599.33-600.53 |
Water vapor |
H2O |
620.700 |
620.08-621.32 |
Hydrogen chloride |
HCl |
625.040 |
624.41-625.67 |
Hydrogen chloride |
HCl |
625.980 |
625.35-626.61 |
Carbon monosulphide |
CS |
636.532 |
634.41-637.17 |
Carbon monoxide |
13CO |
661.067 |
658.86-661.73 |
Carbon monoxide |
CO |
691.473 |
689.17-692.16 |
Oxygen |
O2 |
715.393 |
714.68-716.11 |
Carbon monosulphide |
CS |
734.324 |
733.59-735.06 |
Water vapor |
H2O |
752.033 |
751.28-752.79 |
Oxygen |
O2 |
773.840 |
773.07-774.61 |
Hydrogen cyanide |
HCN |
797.433 |
794.77-798.23 |
Formylium |
HCO+ |
802.653 |
799.98-803.46 |
Carbon monoxide |
CO |
806.652 |
803.96-807.46 |
Carbon |
C I |
809.350 |
806.65-810.16 |
Carbon monosulphide |
CS |
832.057 |
829.28-832.89 |
Oxygen |
O2 |
834.146 |
833.31-834.98 |
Carbon monosulphide |
CS |
880.899 |
877.96-881.78 |
Water vapor |
H2O |
916.172 |
915.26-917.09 |
Carbon monoxide |
CO |
921.800 |
918.72-922.72 |
Carbon monosulphide |
CS |
929.723 |
926.62-930.65 |
Water vapor |
H2O |
970.315 |
969.34-971.29 |
Carbon monosulphide |
CS |
978.529 |
977.55-979.51 |
Water vapor |
H2O |
987.927 |
986.94-988.92 |
SOURCE: Data and further information can be found at the Web site of the European Science Foundation’s Committee on Radio Astronomy Frequencies at http://www.astron.nl/craf/iaulist.htm, accessed October 26, 2005. |