The origin of the near-IR line emission from molecular, low and high ionization gas in the inner kiloparsec of NGC6240
arXiv:1604.06636 · doi:10.1007/s10509-016-2760-x
Abstract
The understating of the origin of the H2 line emission from the central regions of galaxies represent an important key to improve our knowledge about the excitation and ionization conditions of the gas in these locations. Usually these lines can be produced by Starburts, shocks and/or radiation from an active galactic nucleus (AGN). Luminous Infrared Galaxies (LIRG) represent ideal and challenging objects to investigate the origin of the H2 emission, as all processes above can be observed in a single object. In this work, we use K-band integral field spectroscopy to map the emission line flux distributions and kinematics and investigate the origin of the molecular and ionized gas line emission from inner 1.4x2.4 kpc2 of the LIRG NGC6240, known to be the galaxy with strongest H2 line emission. The emission lines show complex profiles at locations between both nuclei and surrounding the northern nucleus, while at locations near the southern nucleus and at 1" west of the northern nucleus, they can be reproduced by a single gaussian component. We found that the H2 emission is originated mainly by thermal processes, possible being dominated by heating of the gas by X-rays from the AGN at locations near both nuclei. For the region between the northern and southern nuclei shocks due to the interacting process may be the main excitation mechanism, as indicated by the high values of the H2l2.12um/Brg line ratio. A contribution of fluorescent excitation may also be important at locations near 1" west of the northern nucleus, which show the lowest line ratios. The [FeII]l2.072um/Brg ratio show a similar trend as observed for H2l2.12um/Brg, suggesting that [FeII] and H2 line emission have similar origins. Finally, the [CaVIII]l2.32um coronal line emission is observed mainly in regions next to the nuclei, suggesting it is originated gas ionized by the radiation from the AGN.
arXiv commentAccepted for publication in ApSS
References in corpus (24)
- Parametric Recovery of Line-of-Sight Velocity Distributions from Absorption-Line Spectra of Galaxies via Penalized Likelihood
- Discovery of a binary AGN in the ultraluminous infrared galaxy NGC 6240 using Chandra
- Kinemetry: a generalisation of photometry to the higher moments of the line-of-sight velocity distribution
- Mapping of the molecular gas inflow towards the Seyfert nucleus of NGC4051 using Gemini NIFS
- Evidence for CO shock excitation in NGC 6240 from Herschel SPIRE spectroscopy
- Molecular Hydrogen and [FeII] in Active Galactic Nuclei
- Feeding Versus Feedback in AGNs from Near-Infrared IFU Observations: The Case of Mrk79
- Near-infrared spectroscopy of nearby Seyfert galaxies. I. First results
- Stellar Dynamics and the implications on the merger evolution in NGC6240
- The Gemini spectral library of near-IR late type stellar templates and its application for velocity dispersion measurements
- Molecular Hydrogen and [Fe II] in Active Galactic Nuclei III: LINERS and Star Forming Galaxies
- Compact molecular disc and ionized gas outflows within 350 pc of the active nucleus of Mrk 1066
- NGC6240: Merger-Induced Star Formation & Gas Dynamics
- Feeding and feedback in the active nucleus of Mrk 1157 probed with Gemini Near-Infrared Integral-Field Spectrograph
- Understanding the two-dimensional ionization structure in luminous infrared galaxies. A near-IR integral field spectroscopy perspective
- Feeding Versus Feedback in AGN from Near-Infrared IFU Observations XI: NGC 2110
- High resolution mapping of CO(1-0) in NGC6240
- Feeding Versus Feedback in NGC1068 probed with Gemini NIFS. I. Excitation
- PROFIT: a new alternative for emission-line PROfile FITting
- X-rays as dominant excitation mechanism of [Fe ii] and H2 emission lines in active galaxies
- Mass of the Southern Black Hole in NGC 6240 from Laser Guide Star Adaptive Optics
- Modelling the Molecular Gas in NGC 6240
- Near- to Mid- Infrared Imaging and Spectroscopy of Two Buried AGNs of the Nearby Merging Galaxy NGC 6240 with Subaru/IRCS+AO and GTC/CanariCam
- High-Resolution Imaging of Water Maser Emission in the active galaxies NGC 6240 and M51
Cited by in corpus (7)
- The AGNIFS survey: spatially resolved observations of hot molecular and ionised outflows in nearby active galaxies
- The AGNIFS survey: distribution and excitation of the hot molecular and ionised gas in the inner kpc of nearby AGN hosts
- Imaging the Molecular Outflows of the Prototypical ULIRG NGC 6240 with ALMA
- Gemini NIFS survey of feeding and feedback in nearbyActive Galaxies - III. Ionized versus warm molecular gasmasses and distributions
- The JWST/NIRSpec view of the nuclear region in the prototypical merging galaxy NGC 6240
- Ionized regions in the central arcsecond of NGC 1068. YJHK spatially resolved spectroscopy
- Outflowing shocked gas dominates the NIR H emission from the dual AGN NGC6240