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Understanding the chemical complexity in Circumstellar Envelopes of C-Rich AGB stars: the case of IRC +10216

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Abstract

The circumstellar envelopes of carbon-rich AGB stars show a chemical complexity that is exemplified by the prototypical object IRC +10216, in which about 60 different molecules have been detected to date. Most of these species are carbon chains of the type C n H, C n H2, C n N, HC n N. We present the detection of new species (CH2CHCN, CH2CN, H2CS, CH3CCH and C3O) achieved thanks to the systematic observation of the full 3 mm window with the IRAM 30m telescope plus some ARO 12m observations. All these species, known to exist in the interstellar medium, are detected for the first time in a circumstellar envelope around an AGB star. These five molecules are most likely formed in the outer expanding envelope rather than in the stellar photosphere. A pure gas phase chemical model of the circumstellar envelope is reasonably successful in explaining the derived abundances, and additionally allows to elucidate the chemical formation routes and to predict the spatial distribution of the detected species.

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References

  • Agúndez, M., Cernicharo, J.: Oxygen chemistry in the circumstellar envelope of the carbon-rich star IRC +10216. Astrophys. J. 650, 374 (2006)

    Article  ADS  Google Scholar 

  • Becklin, E.E., Frogel, J.A., Hyland, A.R., Kristian, J., Neugebauer, G.: The unusual infrared object IRC +10216. Astrophys. J. Lett. 158, L133 (1969)

    Article  ADS  Google Scholar 

  • Brown, R.D., et al.: Tricarbon monoxide in TMC-1. Astrophys. J. 297, 302 (1985)

    Article  ADS  Google Scholar 

  • Cernicharo, J., Guélin, M., Kahane, C.: A λ 2 mm molecular line survey of the C-star envelope IRC+10216. Astron. Astrophys. Suppl. Ser. 142, 181 (2000)

    Article  ADS  Google Scholar 

  • Choi, N., Blitz, M.A., McKee, K., Pilling, M.J., Seakins, P.W.: H atom branching ratios from the reactions of CN radicals with C2H2 and C2H4. Chem. Phys. Lett. 384, 68 (2004)

    Article  Google Scholar 

  • Ford, K.E.S., Neufeld, D.A., Schilke, P., Melnick, G.J.: Detection of formaldehyde toward the extreme carbon star IRC +10216. Astrophys. J. 614, 990 (2004)

    Article  ADS  Google Scholar 

  • Glassgold, A.E.: Circumstellar photochemistry. Annu. Rev. Astron. Astrophys. 34, 241 (1996)

    Article  ADS  Google Scholar 

  • Herbst, E., Leung, C.M.: The gas phase production of CH2CN and other organo-nitrogen species in dense interstellar clouds. Astron. Astrophys. 233, 177 (1990)

    ADS  Google Scholar 

  • Irvine, W.M., et al.: The increasing chemical complexity of the Taurus dark clouds—detection of CH3CCH and C4H. Astrophys. J. Lett. 248, 113 (1981)

    Article  ADS  Google Scholar 

  • Irvine, W.M., et al.: Identification of the interstellar cyanomethyl radical (CH2CN) in the molecular clouds TMC-1 and Sagittarius B2. Astrophys. J. Lett. 334, 107 (1988)

    Article  ADS  Google Scholar 

  • Irvine, W.M., et al.: Observations of some oxygen-containing and sulfur-containing organic molecules in cold dark clouds. Astrophys. J. 342, 871 (1989)

    Article  ADS  Google Scholar 

  • Kaifu, N., et al.: A 8.8-50 GHz complete spectral line survey toward TMC-1 I. Survey data. Publ. Astron. Soc. Jpn. 56, 69 (2004)

    ADS  Google Scholar 

  • Lafont, S., Lucas, R., Omont, A.: Molecular abundances in IRC +10216. Astron. Astrophys. 106, 201 (1982)

    ADS  Google Scholar 

  • Le Teuff, Y.H., Millar, T.J., Marckwick, A.J.: The UMIST database for astrochemistry 1999. Astron. Astrophys. Suppl. Ser. 146, 157 (2000)

    Article  ADS  Google Scholar 

  • Matthews, H.E., Sears, T.J.: The detection of vinyl cyanide in TMC-1. Astrophys. J. 272, 149 (1983)

    Article  ADS  Google Scholar 

  • Millar, T.J., Herbst, E., Bettens, R.P.A.: Large molecules in the envelope surrounding IRC +10216. Mon. Not. Roy. Astron. Soc. 316, 195 (2000)

    Article  ADS  Google Scholar 

  • Sims, I.R., Queffelec, J.-L., Travers, D., Rowe, B.R., Herbert, L.B., Karthauser, J., Smith, I.W.M.: Rate constants for the reactions of CN with hydrocarbons at low and ultra-low temperatures. Chem. Phys. Lett. 211, 461 (1993)

    Article  ADS  Google Scholar 

  • Smith, I.W.M., Herbst, E., Chang, Q.: Rapid neutral-neutral reactions at low temperatures: a new network and first results for TMC-1. Mon. Not. Roy. Astron. Soc. 350, 323 (2004)

    Article  ADS  Google Scholar 

  • Tenenbaum, E.D., Apponi, A.J., Ziurys, L.M., Agúndez, M., Cernicharo, J., Pardo, J.R., Guélin, M.: Detection of C3O in IRC +10216: oxygen-carbon chemistry in the outer envelope. Astrophys. J. Lett. 649, 17 (2006)

    Article  ADS  Google Scholar 

  • Trigilio, C., Palumbo, M.E., Siringo, C., Leto, P.: Science with ALMA: a new era for astrophysics. Springer Astrophysics and Space Science, Madrid (2007)

    Google Scholar 

  • Turner, B.E., Friberg, P., Irvine, W.M., Saito, S., Yamamoto, S.: Interstellar cyanomethane. Astrophys. J. 355, 546 (1990)

    Article  ADS  Google Scholar 

Download references

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Authors and Affiliations

  1. Departamento de Astrofísica Molecular e Infrarroja, Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006, Madrid, Spain

    M. Agúndez, J. Cernicharo, J. R. Pardo & J. P. Fonfría Expósito

  2. Institut de Radioastronomie Millimétrique, 300 rue de la Piscine, 38406, St. Martin d’Heres, France

    M. Guélin

  3. Departments of Chemistry and Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ, 85721, USA

    E. D. Tenenbaum, L. M. Ziurys & A. J. Apponi

Authors
  1. M. Agúndez
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  2. J. Cernicharo
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  3. J. R. Pardo
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  4. J. P. Fonfría Expósito
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  5. M. Guélin
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  6. E. D. Tenenbaum
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  7. L. M. Ziurys
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  8. A. J. Apponi
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Correspondence to M. Agúndez.

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Agúndez, M., Cernicharo, J., Pardo, J.R. et al. Understanding the chemical complexity in Circumstellar Envelopes of C-Rich AGB stars: the case of IRC +10216. Astrophys Space Sci 313, 229–233 (2008). https://doi.org/10.1007/s10509-007-9495-7

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  • DOI: https://doi.org/10.1007/s10509-007-9495-7

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