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Title: Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA

Abstract

We compute the molecular line emission of massive protostellar disks by solving the equation of radiative transfer through the cores and disks produced by the recent radiation-hydrodynamic simulations of Krumholz, Klein, & McKee. We find that in several representative lines the disks show brightness temperatures of hundreds of Kelvin over velocity channels {approx} 10 km s{sup -1} wide, extending over regions hundreds of AU in size. We process the computed intensities to model the performance of next-generation radio and submillimeter telescopes. Our calculations show that observations using facilities such as the EVLA and ALMA should be able to detect massive protostellar disks and measure their rotation curves, at least in the nearest massive star-forming regions. They should also detect significant sub-structure and non-axisymmetry in the disks, and in some cases may be able to detect star-disk velocity offsets of a few km s{sup -1}, both of which are the result of strong gravitational instability in massive disks. We use our simulations to explore the strengths and weaknesses of different observational techniques, and we also discuss how observations of massive protostellar disks may be used to distinguish between alternative models of massive star formation.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
943820
Report Number(s):
UCRL-JRNL-230765
Journal ID: ISSN 0004-637X; ASJOAB; TRN: US200902%%426
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, vol. 665, no. 1, August 1, 2007, pp. 478-491; Journal Volume: 665; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
99 GENERAL AND MISCELLANEOUS; BRIGHTNESS; GRAVITATIONAL INSTABILITY; PERFORMANCE; RADIANT HEAT TRANSFER; ROTATION; STARS; TELESCOPES; VELOCITY

Citation Formats

Krumholz, M R, Klein, R I, and McKee, C F. Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA. United States: N. p., 2007. Web. doi:10.1086/519305.
Krumholz, M R, Klein, R I, & McKee, C F. Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA. United States. doi:10.1086/519305.
Krumholz, M R, Klein, R I, and McKee, C F. Mon . "Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA". United States. doi:10.1086/519305. https://www.osti.gov/servlets/purl/943820.
@article{osti_943820,
title = {Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA},
author = {Krumholz, M R and Klein, R I and McKee, C F},
abstractNote = {We compute the molecular line emission of massive protostellar disks by solving the equation of radiative transfer through the cores and disks produced by the recent radiation-hydrodynamic simulations of Krumholz, Klein, & McKee. We find that in several representative lines the disks show brightness temperatures of hundreds of Kelvin over velocity channels {approx} 10 km s{sup -1} wide, extending over regions hundreds of AU in size. We process the computed intensities to model the performance of next-generation radio and submillimeter telescopes. Our calculations show that observations using facilities such as the EVLA and ALMA should be able to detect massive protostellar disks and measure their rotation curves, at least in the nearest massive star-forming regions. They should also detect significant sub-structure and non-axisymmetry in the disks, and in some cases may be able to detect star-disk velocity offsets of a few km s{sup -1}, both of which are the result of strong gravitational instability in massive disks. We use our simulations to explore the strengths and weaknesses of different observational techniques, and we also discuss how observations of massive protostellar disks may be used to distinguish between alternative models of massive star formation.},
doi = {10.1086/519305},
journal = {Astrophysical Journal, vol. 665, no. 1, August 1, 2007, pp. 478-491},
number = 1,
volume = 665,
place = {United States},
year = {Mon May 07 00:00:00 EDT 2007},
month = {Mon May 07 00:00:00 EDT 2007}
}
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