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NIST Observed Interstellar Molecular Microwave Transitions Database - SRD 116

Published by National Institute of Standards and Technology | National Institute of Standards and Technology | Metadata Last Checked: August 02, 2025 | Last Modified: 2009-09-01 00:00:00
This database contains critically evaluated transition frequencies for the molecular transitions detected in interstellar and circumstellar clouds reported in the literature through mid-2008. The tabulated transition frequencies are recommended for reference in future astronomical observations in the centimeter and millimeter wavelength regions. The transition frequencies have been selected through a critical examination and analysis of the laboratory spectral data obtained from the literature. The information tabulated includes the species identity, transition frequency, uncertainty, and quantum state labels. For convenience, representative line antenna temperatures are listed for a typical astronomical source for each transition, and the references are cited for the laboratory and astronomical literature that have been employed. 2009 Revision

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