Near-infrared line imaging of NGC 6240 - Collision shock and nuclear starburst

Werf, P. P. van der; Genzel, R.; Krabbe, Â. C.; Blietz, M.; Lutz, D.; Drapatz, S.; Ward, M. J.; Forbes, Duncan A.

doi:10.1086/172384

Cited by 116 publications

(115 citation statements)

References 0 publications

Supporting

Mentioning

100

Contrasting

Order By: Relevance

“…One method for estimating the [C ii] contribution from ionized gas is to rely on H ii region modeling, as presented by Carral et al (1994) and Satyapal et al (2003) 63 lm to [C ii] 158 lm ratios greater than 3. Such ratios are roughly consistent with those seen in AGNs and starbursts with a strong shock-excited component (e.g., Spinoglio & Malkan 1992;van der Werf et al 1993). Based on the generally low ratio ($1) of [O i] to [C ii] emission in the ULIRGs, however, we believe that the contribution to the [O i] emission from shock-excited gas is small.…”

Section: Sourcesupporting

confidence: 85%

The [Cii] 158 Micron Line Deficit in Ultraluminous Infrared Galaxies Revisited

Luhman

Satyapal

Fischer

et al. 2003

ApJ

Self Cite

214

350

View full text Add to dashboard Cite

We present a study of the [C ii] 157.74 lm fine-structure line in a sample of 15 ultraluminous infrared (IR) galaxies (IR luminosity L IR k10 12 L ; ULIRGs) using the Long Wavelength Spectrometer (LWS) on the Infrared Space Observatory (ISO). We confirm the observed order of magnitude deficit (compared to normal and starburst galaxies) in the strength of the [C ii] line relative to the far-infrared (FIR) dust continuum emission found in our initial report, but here with a sample that is twice as large. This result suggests that the deficit is a general phenomenon affecting 4 out of 5 ULIRGs. We present an analysis using observations of generally acknowledged photodissociation region (PDR) tracers ([C ii], [O i] 63 and 145 lm, and FIR continuum emission), which suggests that a high ultraviolet flux G 0 incident on a moderate density n PDR could explain the deficit. However, comparisons with other ULIRG observations, including CO (1-0), [C i] (1-0), and 6.2 lm polycyclic aromatic hydrocarbon (PAH) emission, suggest that high G 0 =n PDRs alone cannot produce a self-consistent solution that is compatible with all of the observations. We propose that non-PDR contributions to the FIR continuum can explain the apparent [C ii] deficiency. Here, unusually high G 0 and/ or n physical conditions in ULIRGs as compared to those in normal and starburst galaxies are not required to explain the [C ii] deficit. Dust-bounded photoionization regions, which generate much of the FIR emission but do not contribute significant [C ii] emission, offer one possible physical origin for this additional non-PDR component. Such environments may also contribute to the observed suppression of FIR fine-structure emission from ionized gas and PAHs, as well as the warmer FIR colors found in ULIRGs. The implications for observations at higher redshifts are also revisited.

show abstract

Section: Sourcesupporting

confidence: 85%

The [Cii] 158 Micron Line Deficit in Ultraluminous Infrared Galaxies Revisited

Luhman

Satyapal

Fischer

et al. 2003

ApJ

Self Cite

214

350

View full text Add to dashboard Cite

show abstract

“…This line contains 0.012% of the bolometric luminosity of NGC 6240, which is considerably higher than any other galaxy ( Van der Werf et al 1993). Together the vibrational lines may account for 0.1% of the total bolometric luminosity.…”

Section: Extended H 2 Rotational Line Emission In the Disk Of Ngc 891mentioning

confidence: 74%

H₂ Emission as a Diagnostic of Physical Processes in Starforming Galaxies

Werf

2000

Molecular Hydrogen in Space

View full text Add to dashboard Cite

Observations and interpretation of extragalactic rotational and rovibrational H2 emission are reviewed. Direct observations of H2 lines do not trace bulk H2 mass, but excitation rate. As such, the H2 lines are unique diagnostics, if the excitation mechanism can be determined, which generally requires high-quality spectroscopy and suitable additional data. The diagnostic power of the H2 lines is illustrated by two cases studies: H2 purely rotational line emission from the disk of the nearby spiral galaxy NGC 891 and high resolution imaging and spectroscopy of H2 vibrational line emision from the luminous merger NGC 6240.

show abstract

“…H 2 emission line is expected to be excited in the shocks. Van der Werf et al (1993) and Sugai et al (1997) have observed bright H 2 emission line in the galactic central region of NGC 6240 and they conclude that the H 2 emission is excited by shock.…”

Section: Summary and Discussionmentioning

confidence: 99%

Effects of a Supermassive Black Hole Binary on a Nuclear Gas Disk

Matsui

Habe

Saitoh

2008

Mapping the Galaxy and Nearby Galaxies

View full text Add to dashboard Cite

We study influence of a galactic central supermassive black hole (SMBH) binary on gas dynamics and star formation activity in a nuclear gas disk by making three-dimensional Tree+SPH simulations. Due to orbital motions of SMBHs, there are various resonances between gas motion and the SMBH binary motion. We have shown that these resonances create some characteristic structures of gas in the nuclear gas disk, for examples, gas elongated or filament structures, formation of gaseous spiral arms, and small gas disks around SMBHs. In these gaseous dense regions, active star formations are induced. As the result, many star burst regions are formed in the nuclear region.

show abstract

Near-infrared line imaging of NGC 6240 - Collision shock and nuclear starburst

Cited by 116 publications

References 0 publications

The [Cii] 158 Micron Line Deficit in Ultraluminous Infrared Galaxies Revisited

The [Cii] 158 Micron Line Deficit in Ultraluminous Infrared Galaxies Revisited

H₂ Emission as a Diagnostic of Physical Processes in Starforming Galaxies

Effects of a Supermassive Black Hole Binary on a Nuclear Gas Disk

Contact Info

Product

Resources

About

Near-infrared line imaging of NGC 6240 - Collision shock and nuclear starburst

Cited by 116 publications

References 0 publications

The [Cii] 158 Micron Line Deficit in Ultraluminous Infrared Galaxies Revisited

The [Cii] 158 Micron Line Deficit in Ultraluminous Infrared Galaxies Revisited

H2 Emission as a Diagnostic of Physical Processes in Starforming Galaxies

Effects of a Supermassive Black Hole Binary on a Nuclear Gas Disk

Contact Info

Product

Resources

About

H₂ Emission as a Diagnostic of Physical Processes in Starforming Galaxies