Spatially resolved near-infrared spectroscopy of NGC 6240

Journal Article · Sun Jul 01 04:00:00 EDT 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/168893· OSTI ID:6863382

Elston, R; Maloney, P ^[1]

---

1. Kitt Peak National Observatory, Tucson, AZ (USA) Leiden Rijksuniversiteit, Sterrewacht (Netherlands)

The infrared-luminous galaxy NGC 6240 has been observed using a long-slit near-IR spectrometer. The very strong 1-0 S(1) line of molecular hydrogen (H2) is extended over about 9 arcsec and shows a distinct component of emission extending to the south-east of the nucleus, with a velocity of about 300 km/s lower than the diffuse nuclear emission. Only very weak emission is found in the 5-3 O(3) and 6-4 Q(1) lines of H2, suggesting little contribution from fluorescently excited H2. Fe II emission, which requires stronger shocks to excite than the 1-0 S(1) line, is slightly more concentrated and displaced to the north of the nucleus and shows a different velocity structure than the S(1) line. No strong Br-gamma emission from the nucleus but some weak patches of extranuclear emission are probably detected. It is suggested that the strong H2 emission is due to slow shocks being driven into molecular clouds by the collision of the clouds with the diffuse interstellar medium (ISM) of the other galaxy in this merging system. 22 refs.

• OSTI ID: 6863382
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 357; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BASIC INTERACTIONS
COSMIC GASES
ELECTROMAGNETIC RADIATION
ELEMENTS
EMISSION SPECTRA
FLUIDS
GALAXIES
GASES
GRAVITATIONAL INTERACTIONS
HYDROGEN
INFRARED RADIATION
INFRARED SPECTRA
INTERACTIONS
INTERSTELLAR SPACE
NEAR INFRARED RADIATION
NONMETALS
RADIATIONS
RESOLUTION
SHOCK WAVES
SPACE
SPATIAL RESOLUTION
SPECTRA
STAR EVOLUTION