Complex organic molecules in an early stage of protostellar evolution

Conference paper

Abstract

We have detected the rotational lines of HCOOCH3 toward a Class 0 low-mass protostar, NGC1333 IRAS4B, which is reported to be extremely young according to the dynamical age of the molecular outflow (a few 100 yr). This suggests that the complex organic molecules appear from the very early stage of protostellar evolution. On the other hand, the complex organic molecules are not detected in a more evolved protostar, L1527. We have also found a similar trend in a massive star forming region, NGC2264. The HCOOCH3 emission is almost absent toward IRS1, whereas it is concentrated near MMS3, which is younger than IRS1. In addition, the HCOOCH3 intensity peak is slightly shifted from the dust emission peak, as is seen in the Orion KL Compact Ridge, giving an important clue to solve its origin.

Keywords

ISM: individual (NGC1333 IRAS4B) ISM: individual (L1527) ISM: individual (NGC2264) ISM: molecules Stars: formation 

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References

  1. Allen, D.A.: Infrared objects in H II Regions. Astrophys. J. 172, L55 (1972) CrossRefADSGoogle Scholar
  2. Bachiller, R., et al.: Molecules in protostellar outflows. In: Complex Molecules in Space, Denmark (2006) Google Scholar
  3. Beuther, H., et al.: Line imaging of Orion KL at 865 mum with the submillimeter array. Astrophys. J. 632, 355 (2005) CrossRefADSGoogle Scholar
  4. Blake, G.A., et al.: Molecular abundances in OMC-1. Astrophys. J. 315, 621 (1987) CrossRefADSGoogle Scholar
  5. Bottinelli, S., et al.: Complex molecules in the hot core of the low-mass protostar NGC 1333 IRAS 4A. Astrophys. J. 615, 354 (2004a) CrossRefADSGoogle Scholar
  6. Bottinelli, S., et al.: Near-arcsecond resolution observations of the hot corino of the solar-type protostar IRAS 16293-2422. Astrophys. J. 617, L69 (2004b) CrossRefADSGoogle Scholar
  7. Bottinelli, S., et al.: Hot corinos in NGC1333-IRAS4B and IRAS2A. Astron. Astrophys. 463, 601 (2007) CrossRefADSGoogle Scholar
  8. Cazaux, S., et al.: The hot core around the low-mass protostar IRAS 16293-2422. Astrophys. J. 593, L51 (2003) CrossRefADSGoogle Scholar
  9. Choi, M.: High-resolution observations of the molecular clouds in the NGC 1333 IRAS 4 region. Astrophys. J. 553, 219 (2001) CrossRefADSGoogle Scholar
  10. Garrod, R.T., et al.: Formation of methyl formate and other organic species in the warm-up phase of hot molecular cores. Astron. Astrophys. 457, 927 (2006) CrossRefADSGoogle Scholar
  11. Jørgensen, J.K., et al.: Physical structure and CO abundance of low-mass protostellar envelopes. Astron. Astrophys. 389, 908 (2002) CrossRefADSGoogle Scholar
  12. Jørgensen, J.K., et al.: Probing the inner 200 AU of low-mass protostars with the submillimeter array. Astrophys. J. 632, 973 (2005) CrossRefADSGoogle Scholar
  13. Kuan, Y.-J., et al.: Organic molecules in low-mass protostellar hot cores. Astrophys. J. 616, L27 (2004) CrossRefADSGoogle Scholar
  14. Liu, S.-Y., et al.: Formic acid in Orion KL from 1 millimeter observations with the Berkeley-Illinois-Maryland Association Array. Astrophys. J. 576, 255 (2002) CrossRefADSGoogle Scholar
  15. Maret, S., et al.: The H2CO abundance in the inner warm regions of low mass protostellar envelopes. Astron. Astrophys. 416, 577 (2004) CrossRefADSGoogle Scholar
  16. Millar, T.J., et al.: Gas phase reactions and rate coefficients for use in astrochemistry. Astron. Astrophys. Suppl. Ser. 87, 585 (1991) ADSGoogle Scholar
  17. Nomura, H., et al.: The physical and chemical structure of hot molecular cores. Astron. Astrophys. 414, 409 (2004) CrossRefADSGoogle Scholar
  18. Remijan, A., et al.: A survey of acetic acid toward hot molecular cores. Astrophys. J. 590, 314 (2003) CrossRefADSGoogle Scholar
  19. Sakai, N., et al.: Detection of HCOOCH3 toward a low-mass protostar, NGC 1333 IRAS 4B. Publ. Astron. Soc. Jpn. 58, L15 (2006) ADSGoogle Scholar
  20. Sakai, N., et al.: Methyl formate in the NGC2264 IRS1 Region. Astrophys. J. 660, 363 (2007) CrossRefADSGoogle Scholar
  21. Schreyer, K., et al.: A molecular line and infrared study of NGC 2264 IRS 1. Astron. Astrophys. 326, 347 (1997) ADSGoogle Scholar
  22. Ward-Thompson, D., et al.: Dust emission from star-forming regions. VI. The submillimetre YSO cluster in NGC 2264. Astron. Astrophys. 355, 1122 (2000) ADSGoogle Scholar
  23. Wyrowski, F., et al.: Hot gas and dust in a protostellar cluster near W3(OH). Astrophys. J. 514, L43 (1999) CrossRefADSGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Department of PhysicsThe University of TokyoTokyoJapan
  2. 2.Nobeyama Radio ObservatoryNaganoJapan

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