Detection of C5 in the Circumstellar Shell of IRC+10216

  title={Detection of C5 in the Circumstellar Shell of IRC+10216},
  author={Peter F. Bernath and Kenneth H. Hinkle and John Joseph Keady},
  pages={562 - 564}
The C5 molecule has been identified in the infrared spectrum of the prototypical obscured carbon star, IRC+10216. In addition to their astrophysical importance, pure carbon chain molecules such as C5 are of interest in the chemistry of flames and propellants. 

On the detection of the linear C5 molecule in the interstellar medium

An upper limit of the column density of the C5 linear molecule in translucent interstellar clouds is estimated from high-resolution (R=80 000) and very high signal-to-noise ratio (∼1000) echelle

Interstellar C3 toward HD 210121

We report the detection of the 405 nm band of interstellar C3 in absorption toward HD 210121. The abundance of triatomic carbon is approximately 1/17 of that of diatomic carbon in the same diuse

Large molecules in the envelope surrounding IRC+10216

ABSTRA C T A new chemical model of the circumstellar envelope surrounding the carbon-rich star IRC110216 is developed that includes carbon-containing molecules with up to 23 carbon atoms. The model

Observation of an infrared frequency of the C4 molecule

A Fourier transform infrared isotopic study of the products from the vacuum ultraviolet photolysis of diacetylene and 1,3‐butadiene trapped in solid argon has enabled the identification of the 1543.4

A New Infrared Band in Interstellar and Circumstellar Clouds: C4 or C4H?

We report on the detection with the Infrared Space Observatory of a molecular band at 57.5 μm (174 cm-1) in carbon-rich evolved stars and in Sgr B2. Taking into account the chemistry of these

Carbon Chemistry in IRC+10216: Infrared Detection of Diacetylene

We present the detection of C4H2 for first time in the envelope of the C-rich AGB star IRC+10216, based on high spectral resolution mid-infrared observations carried out with the Texas

Far-infrared Detection of C3 in Sagittarius B2 and IRC +10216

Nine lines of the nu2 bending mode of triatomic carbon, C3, are detected in the direction of Sagittarius B2 and it is suggested that these molecules could be the dominant carriers of emission/absorption in the spectrum of bright far-infrared sources.

The Abundance of C2H4 in the Circumstellar Envelope of IRC+10216.

High spectral resolution mid-IR observations of ethylene (C2H4) towards the AGB star IRC+10216 were obtained using the Texas Echelon Cross Echelle Spectrograph (TEXES) at the NASA Infrared Telescope Facility (IRTF), and it is found to be rotationally under local thermodynamical equilibrium (LTE) and vibrationally out of LTE.

Infrared laser spectroscopy of the linear C13 carbon cluster.

This definitive structural characterization of a carbon cluster in the intermediate size range between C10 and C20 is in apparent conflict with theoretical calculations, which predict that clusters of this size should exist as planar monocyclic rings.


Observations were made for a number of carbon-rich circumstellar envelopes using the Phoenix spectrograph on the Gemini South telescope to determine the abundance of small carbon chain molecules.



The circumstellar shell of IRC + 10216 - Photo-chemistry of C2H and CN

Cartographie de l'enveloppe circumstellaire de cette etoile carbonee pour toutes les transitions hyperfines dans l'etat de base de C 2 H et CN

Evidence for ion-molecular chemistry in the envelope of IRC +10216

Results of aperture synthesis mapping of line emission from the molecules HNC, C/sub 2/H, and HC/sub 3/N in the envelope of the carbon star IRC +10216 are presented. The observations of the molecules

Molecular ions in the circumstellar envelope of IRC+10216

Assuming a steady and spherically symmetric mass loss, the spatial distribution of the ionization in a C-rich circumstellar envelope (CSE) is calculated, and it is shown that molecular ions dominate


The λ4050 bands, excited with the pure C13 isotope, have been photographed under high resolution. The lines of the strongest band show a 3: 1 intensity alternation. The B values of the C13 band are

The IRC + 10216 circumstellar envelope. I - Models for the dust and gas

Very high resoluton infrared spectra for the gas flow from the IRC + 10216 photosphere is interpreted using a detailed empirical model of the density, temperature, and velocity profiles of the gas.

CRL 2688: a post-carbon-star object and probable planetary nebula progenitor.

Millimeter-wavelength emission is observed toward CRL 2688 from H/sup 12/CN, H/sup 13/CN, CS, and HC/sub 3/N. The similarity of this emission and that from the molecular envelope of the carbon star

Photofragmentation of mass‐resolved carbon cluster ions: Observation of a ‘‘magic’’ neutral fragment

Mass‐resolved carbon cluster ions from C+3 to C+20 have been fragmented with 248 nm light. For any initial cluster C+n, the dominant fragment is C+n−3. The fragmentation is primarily linear in laser

C2H in the 2 micron infrared spectrum of IRC +10216

Nearly 30 lines of C/sub 2/H in two bands at 4011 and 4108/cm have been identified in the 2 micron spectrum of IRC +10216. A rotational temperature of about 12.5 + or - 1.5 K and a column density of