Near Infrared Emission of Neutral Carbon from Photon-Dominated Regions

Detailed calculations are reported of the intensities of the near infrared forbidden lines of neutral carbon atoms at λ 985.0 nm, 982.3 nm and 872.7 nm emitted from dense clouds subjected to intense radiation fields. The metastable levels that produce the lines are excited by radiative recombination of the C+ ions produced by photoionization. Impacts of electrons with C atoms in the heated edge zones of the clouds contribute an insignificant part to the excitation. The lines observed in M42 and NGC 2024 can be interpreted as arising in gas with densities in excess of 105 cm−3 and radiation fields with intensities between 103 and 106 times the average interstellar field intensity. Radiative recombination of C+ ions may also be an important source of the emission lines detected in the planetary nebulae NGC 6270 and NGC 7027.

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Infrared Emission-Lines and the Stellar Temperature

Symposium - International Astronomical Union ◽

10.1017/s0074180900170196 ◽

1993 ◽

Vol 155 ◽

pp. 89-89 ◽

Cited By ~ 1

Author(s):

Sueli M. Viegas ◽

Ruth Gruenwald

Keyword(s):

Near Infrared ◽

Planetary Nebulae ◽

Infrared Emission ◽

Emission Lines ◽

Heavy Elements ◽

Atomic Transitions ◽

Stellar Temperature ◽

Near Infrared Emission

Observations of near infrared emission-lines are becoming available and can be a powerful tool to improve our knowledge on planetary nebulae properties. For wavelengths in the range 1 to 5 μm, the emission-lines correspond to atomic transitions of high ionized species of heavy elements. In particular, the [Si VI] 1.96μm and [Si VII] 2.48μm lines have already been detected (Ashley and Hyland, 1988).

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Neutron-Capture Elements in Planetary Nebulae: Identification of Two Near-Infrared Emission Lines as [K[CLC]r[/CLC] [CSC]iii[/CSC]] and [S[CLC]e[/CLC] [CSC]iv[/CSC]]

The Astrophysical Journal ◽

10.1086/319645 ◽

2001 ◽

Vol 550 (2) ◽

pp. L223-L226 ◽

Cited By ~ 44

Author(s):

Harriet L. Dinerstein

Keyword(s):

Neutron Capture ◽

Near Infrared ◽

Planetary Nebulae ◽

Infrared Emission ◽

Emission Lines ◽

Near Infrared Emission

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Novel calibrations of virial black hole mass estimators in active galaxies based on X-ray luminosity and optical/near-infrared emission lines

Astronomy and Astrophysics ◽

10.1051/0004-6361/201629380 ◽

2017 ◽

Vol 598 ◽

pp. A51 ◽

Cited By ~ 8

Author(s):

F. Ricci ◽

F. La Franca ◽

F. Onori ◽

S. Bianchi

Keyword(s):

Black Hole ◽

Near Infrared ◽

Infrared Emission ◽

Active Galaxies ◽

Emission Lines ◽

Black Hole Mass ◽

X Ray ◽

Near Infrared Emission

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Near-Infrared Spectroscopy of NGC 253: Starburst and Surroundings

Symposium - International Astronomical Union ◽

10.1017/s0074180900233263 ◽

1996 ◽

Vol 171 ◽

pp. 407-407 ◽

Cited By ~ 1

Author(s):

D. Lutz ◽

F. Prada

Keyword(s):

Stellar Population ◽

Near Infrared ◽

Velocity Dispersion ◽

Mass Function ◽

Infrared Emission ◽

Initial Mass Function ◽

Emission Lines ◽

Lower Mass ◽

Dynamical Mass ◽

Near Infrared Emission

Near-infrared longslit spectra of NGC 253 obtained with IRSPEC at the ESO NTT are presented. By analysis of the 12CO 2.29μm bandhead we find that the stellar population in the central starburst region (r ∼ 150 pc) rotates more slowly than the gas, but has a velocity dispersion of 128 km/s, about twice the value found for emission lines from the gas in this region. This implies an about five times higher dynamical mass than previously derived (Rieke et al. 1980), removing the need to invoke a lower mass cutoff in the starburst initial mass function. The peak of near-infrared emission is displaced from the dynamical center.

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