Astronomy and Astrophysics Letters dedicated to ISO

The ISO/LWS far infrared spectrum of IRC+10216

J. Cernicharo et al.


We present an ISO Long Wavelength Spectrometer (LWS) grating spectrum of the carbon-rich circumstellar envelope -CSE- of IRC+10216 between 43 and 197 microns . The spectrum consists of strong dust emission plus a forest of emission lines from CO, HCN, H13CN and vibrationally excited HCN (v2=11,20,2 and v1,3=1) . All the CO lines between J=14-13 and J=39-38 have been detected while lines of HCN with Ju as high as 48 have also been observed. The molecular emission arises from the warm and dense gas located in the innermost zone of the CSE. The CO and HCN emission can be easily explained if the vibrational and rotational temperatures are around 700-1500 K.

We also report the tentative detection of the bending mode of the C3 molecule around 62 cm-1 (157.2 microns).

Stars : AGB and post AGB - Stars : individual : IRC+10216 - Stars: circumstellar matter -Infrared: Stars

Full text