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Session 41 - Visible & UV Telescopes.
Display session, Thursday, January 08
Exhibit Hall,

[41.11] Molecular Spectroscopy with the Biggest Night-Sky Spectrograph in the World

D. E. Osterbrock, J. P. Fulbright (LO/UCSC), T. A. Barlow (CASS/UCSD), T. G. Slanger, D. L. Huestis, P. C. Cosby (MPL/SRI)

The emission lines of the night sky, recorded on every astronomical spectrogram, are in many ways a nuisance to observers, but they also provide a highly accurate standard wavelength reference system. There are OH Meinel main-band lines with wavelengths known to 0.00001 Åin every echelle order from \lambda5800 to \lambda10600. the present practical CCD limit.

In addition, using coadded spectra from many observers taken with HIRES on the Keck I telescope, we have constructed a night-sky spectrum averaging 100 hours exposure from \lambda5770 to \lambda7075, decreasing gradually to 30 hours at \lambda8000. On it and similar, earlier, shorter-exposure summed spectra many satellite lines of OH have been identified, also many isotopic main-band lines of ^18OH, and also four main-band lines from the previously unobserved (in the night sky) level v' = 10. Also, many previously unobserved O_2 atmospheric bands have been detected and identified, to higher vibrational energy levels than measured in the laboratory, and the complicated interplay of absorption and emission in the ^16O^16O (with alternate rotational levels nonexistent), ^16O^17O and ^16O^18O bands have been studied.

Program listing for Thursday