Abstract
Class 0 protostars, the youngest type of young stellar objects, show many signs of rapid development from their initial, spheroidal configurations, and therefore are studied intensively for details of the formation of protoplanetary disks within protostellar envelopes. At millimetre wavelengths, kinematic signatures of collapse have been observed in several such protostars, through observations of molecular lines that probe their outer envelopes. It has been suggested that one or more components of the proto-multiple system NGC 1333–IRAS 4 (refs 1, 2) may display signs of an embedded region that is warmer and denser than the bulk of the envelope3,4. Here we report observations that reveal details of the core on Solar System dimensions. We detect in NGC 1333–IRAS 4B a rich emission spectrum of H2O, at wavelengths 20–37 μm, which indicates an origin in extremely dense, warm gas. We can model the emission as infall from a protostellar envelope onto the surface of a deeply embedded, dense disk, and therefore see the development of a protoplanetary disk. This is the only example of mid-infrared water emission from a sample of 30 class 0 objects, perhaps arising from a favourable orientation; alternatively, this may be an early and short-lived stage in the evolution of a protoplanetary disk.
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References
Choi, M., Panis, J.-F. & Evans, N. J. II Berkeley-Illinois-Maryland Association Survey of protostellar collapse candidates in HCO+ and HCN lines. Astrophys. J. Suppl. 122, 519–556 (1999)
Di Francesco, J., Myers, P. C., Wilner, D. J., Ohashi, N. & Mardones, D. Infall, outflow, rotation, and turbulent motions of dense gas within NGC 1333 IRAS 4. Astrophys. J. 562, 770–789 (2001)
Maret, S., Ceccarelli, C., Caux, E., Tielens, A. G. G. M. & Castets, A. Water emission in NGC 1333 – IRAS 4. Astron. Astrophys. 395, 573–585 (2002)
Ceccarelli, C. et al. Water line emission in low-mass protostars. Astron. Astrophys. 342, L21–L24 (1999)
de Zeeuw, P. T., Hoogerwerf, R., de Bruijne, J. H. J., Brown, A. G. A. & Blaauw, A. A. HIPPARCOS census of the nearby OB associations. Astron. J. 117, 354–399 (1999)
Looney, L. W., Mundy, L. G. & Welch, W. J. Unveiling the circumstellar envelope and disk: a subarcsecond survey of circumstellar structures. Astrophys. J. 529, 477–498 (2000)
Knee, L. B. G. & Sandell, G. The molecular outflows in NGC 1333. Astron. Astrophys. 361, 671–684 (2000)
Blake, G. A. et al. A molecular line study of NGC 1333/IRAS 4. Astrophys. J. 441, 689–701 (1995)
Neufeld, D. A., Feuchtgruber, H., Harwit, M. & Melnick, G. J. Infrared Space Observatory observations of far-infrared rotational emission lines of water vapour toward the supergiant star VY Canis Majoris. Astrophys. J. 517, L147–L150 (1999)
Neufeld, D. A. et al. Detection of far-infrared rotational lines of water vapour toward W Hydrae. Astron. Astrophys. 315, L237–L240 (1996)
Scoville, N. Z. & Solomon, P. M. Radiative transfer, excitation, and cooling of molecular emission lines. Astrophys. J. 187, L67–L71 (1974)
Ceccarelli, C., Hollenbach, D. J. & Tielens, A. G. G. M. Far-infrared line emission from collapsing protostellar envelopes. Astrophys. J. 471, 400–426 (1996)
Doty, S. D. & Neufeld, D. A. Models for dense molecular cloud cores. Astrophys. J. 489, 122–142 (1997)
Cassen, P. & Moosman, A. On the formation of protostellar disks. Icarus 48, 353–376 (1981)
Neufeld, D. A. & Hollenbach, D. J. Dense molecular shocks and accretion onto protostellar disks. Astrophys. J. 428, 170–185 (1994)
Ulrich, R. K. An infall model for the T Tauri phenomenon. Astrophys. J. 210, 377–391 (1976)
Kenyon, S. J., Calvet, N. & Hartmann, L. The embedded young stars in the Taurus-Auriga molecular cloud. I — Models for spectral energy distributions. Astrophys. J. 414, 676–694 (1993)
Neufeld, D. A. & Kaufman, M. J. Radiative cooling of warm molecular gas. Astrophys. J. 418, 263–272 (1993)
Sandell, G., Aspin, C., Duncan, W. D., Russell, A. P. G. & Robson, E. I. NGC 1333 IRAS 4: a very young, low-luminosity binary system. Astrophys. J. 376, L17–L20 (1991)
Weingartner, J. C. & Draine, B. T. Dust grain-size distributions and extinction in the Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud. Astrophys. J. 548, 296–309 (2001)
Rothman, L. S. et al. The HITRAN 2004 molecular spectroscopic database. J. Quant. Spectrosc. Radiat. Transf. 96, 139–204 (2004)
Green, S., Maluendes, S. & McLean, A. D. Improved collisional excitation rates for interstellar water. Astrophys. J. Suppl. 85, 181–185 (1993)
Phillips, T. R., Maluendes, S. & Green, S. Collisional excitation of H2O by H2 molecules. Astrophys. J. 107, 467–474 (1996)
Acknowledgements
This work was supported in part by NASA through the Spitzer-IRS Instrument Team, Origins and Astrobiology programmes, and by CONACyT (México). We are grateful to R. Gutermuth for use of the Spitzer-IRAC data on NGC 1333, and to M. Jura, L. Keller, G. Sloan and D. Hollenbach for discussions.
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This file contains Supplementary Discussion to which the main-body text refers, Supplementary Tables 1-2 and Supplementary Figures 1-2 with Legends. Supplementary Figure S1 shows the rotational energy level diagram of water and Supplementary Figure 2 is a large rendition of the high-resolution spectra of NGC 1333 IRAS4B and the model of this object, with all spectral features identified. (PDF 221 kb)
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Watson, D., Bohac, C., Hull, C. et al. The development of a protoplanetary disk from its natal envelope. Nature 448, 1026–1028 (2007). https://doi.org/10.1038/nature06087
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DOI: https://doi.org/10.1038/nature06087
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