National Academies Press: OpenBook

Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition (2015)

Chapter: Appendix D: International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 GHz

« Previous: Appendix C: International Astronomical Union Spectral Lines of Most Importance Below 300 GHz
Suggested Citation:"Appendix D: International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 GHz." National Academies of Sciences, Engineering, and Medicine. 2015. Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition. Washington, DC: The National Academies Press. doi: 10.17226/21774.
×

D

International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 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 (IUCAF) 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 between 300-1000 GHz are listed in Table D.1. Unless otherwise noted, the band limits are Doppler-shifted frequencies corresponding to radial velocities of ±300 km/s, consistent with line radiation occurring in our Milky Way galaxy. Although no formal frequency allocations are established above 275 GHz, the International Telecommunication Union (ITU) Radio Regulation 5.565 urges administrations to take all practicable steps to protect passive services from harmful interference in the frequency range of 275-1000 GHz. Of particular note are the following frequency bands, which are identified for passive use by the Radio Astronomy Service: 275-323 GHz, 327-371 GHz, 388-424 GHz, 426-442 GHz, 453510 GHz, 623-711 GHz, 795-909 GHz, and 926-945 GHz. These frequency bands correspond to atmospheric “windows” (see Figure 2.6) that permit ground-based observations of cosmic sources from high, dry sites.

Suggested Citation:"Appendix D: International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 GHz." National Academies of Sciences, Engineering, and Medicine. 2015. Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition. Washington, DC: The National Academies Press. doi: 10.17226/21774.
×

TABLE D.1 The Most Important Spectral Lines Between 300 and 1000 GHz

Species Formula Frequency (GHz) Suggested Minimum Band (GHz) Notes1
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 2
Water vapor H2O 380.197 379.82-380.58 2
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  
Deuterated water HDO 464.925 464.46-465.39  
Carbon CI 492.162 490.52-492.65  
Deuterated water HDO 509.292 508.78-509.80  
Hydrogen cyanide HCN 531.716 529.94-532.25 2
Carbon monosulphide CS 538.689 536.89-539.23 2
Water vapor H218O 547.676 547.13-548.22 2
Carbon monoxide 13CO 550.926 549.09-551.48 2
Water vapor H2O 556.936 556.38-557.49 2
Ammonia 15NH3 572.113 571.54-572.69 2
Ammonia NH3 572.498 571.93-573.07 2
Carbon monoxide CO 576.268 574.35-576.84 2
Carbon monosulphide CS 587.616 587.03-588.20 2
Deuterated water HDO 599.927 599.33-600.53 2
Water vapor H2O 620.700 620.08-621.32 2
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  
Suggested Citation:"Appendix D: International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 GHz." National Academies of Sciences, Engineering, and Medicine. 2015. Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition. Washington, DC: The National Academies Press. doi: 10.17226/21774.
×
Species Formula Frequency (GHz) Suggested Minimum Band (GHz) Notes1
Oxygen O2 715.393 714.68-716.11 2
Carbon monosulphide CS 734.324 733.59-735.06 2
Water vapor H2O 752.033 751.28-752.79 2
Oxygen O2 773.840 773.07-774.61 2
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 2
Carbon monoxide CO 921.800 918.72-922.72 2
Carbon monosulphide CS 929.723 926.62-930.65  
Water vapor H2O 970.315 969.34-971.29 2
Carbon monosulphide CS 978.529 977.55-979.51 2
Water vapor H2O 987.927 986.94-988.92 2

NOTES:

1. The band limits are the Doppler-shifted frequencies corresponding to radial velocities of ±300 km/s (consistent with line radiation occurring in our Milky Way galaxy).

2. These lines are observable only outside the atmosphere.

SOURCE: Data and further information can be found in International Telecommunication Union, RA 314 Series: Preferred Frequency Bands for Radio Astronomical Measurements, June 2003, http://www.itu.int/dms_pubrec/itu-r/rec/ra/R-REC-RA.314-10-200306-I!!PDF-E.pdf.

Suggested Citation:"Appendix D: International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 GHz." National Academies of Sciences, Engineering, and Medicine. 2015. Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition. Washington, DC: The National Academies Press. doi: 10.17226/21774.
×
Page 241
Suggested Citation:"Appendix D: International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 GHz." National Academies of Sciences, Engineering, and Medicine. 2015. Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition. Washington, DC: The National Academies Press. doi: 10.17226/21774.
×
Page 242
Suggested Citation:"Appendix D: International Astronomical Union Spectral Lines of Most Importance Between 300 and 1000 GHz." National Academies of Sciences, Engineering, and Medicine. 2015. Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition. Washington, DC: The National Academies Press. doi: 10.17226/21774.
×
Page 243
Next: Appendix E: International Astronomical Union Spectral Lines of Most Importance Above 1 THz »
Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition Get This Book
×
Buy Paperback | $72.00 Buy Ebook | $59.99
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF

The electromagnetic spectrum is a vital part of our environment. Measures of radio frequency emissions from natural phenomena enable both practical applications, such as weather predictions and studies of the changing of Earth's climate here at home, and reveal the physical properties of cosmic sources. The spectrum is therefore a resource to be used wisely now and to be protected for future generations.

Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses: Second Edition sets forth the principles for the allocation and protection of spectral bands for services using the radio spectrum for scientific research. This report describes the radio frequency bands used by scientific services and includes relevant regulatory information and discussion of scientific use of frequency bands. This reference will guide spectrum managers and spectrum regulatory bodies on science issues and serve as a resource to scientists and other spectrum users.

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    Switch between the Original Pages, where you can read the report as it appeared in print, and Text Pages for the web version, where you can highlight and search the text.

    « Back Next »
  6. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  7. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  8. ×

    View our suggested citation for this chapter.

    « Back Next »
  9. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!