# Knowledge Bank

## University Libraries and the Office of the Chief Information Officer

The Knowledge Bank is scheduled for regular maintenance on Sunday, April 20th, 8:00 am to 12:00 pm EDT. During this time users will not be able to register, login, or submit content.

# UPPER LIMITS ON THE $C_{60}$ AND $C^{+}_{60}$ ABUNDANCES IN THE INTERSTELLAR MEDIUM

Please use this identifier to cite or link to this item: http://hdl.handle.net/1811/19313

Files Size Format View
1999-RA-05.jpg 95.22Kb JPEG image

 Title: UPPER LIMITS ON THE $C_{60}$ AND $C^{+}_{60}$ ABUNDANCES IN THE INTERSTELLAR MEDIUM Creators: Sellgren, K.; Moutou, C.; Verstraete, L.; Leger, A. Issue Date: 1999 Abstract: We present here the $1145 - 1475 cm^{-1}$ spectrum of the bright reflection nebula NGC 7023, a region where an interstellar molecular cloud is illuminated by ultraviolet radiation from a nearby star. Our astronomical observations are made with the Short Wavelength Spectrometer on the European satellite Infrared Space Observatory. Previous laboratory data show that two vibrational bands of the ionized fullerne $C^{+}_{60}$ fall at 1331 and $1406 cm^{-1}$, while two vibrational bands of the neutral fullerene $C_{60}$ lie at 1190 and $1435 cm^{-1}$. None of these bands are detected in our interstellar spectrum. We estimate an upper limit for the $C^{+}_{60}$ abundance in this interstellar cloud of $< 0.3\%$ of the cosmic abundance of carbon, while $C_{60}$ must be $< 0.2\%$ of the cosmic abundance of carbon. URI: http://hdl.handle.net/1811/19313 Other Identifiers: 1999-RA-05