Open AccessInfrared spectra of cooling flow galaxies
Author(s) -
Jaffe W.,
Bremer M. N.,
Van Der Werf P. P.
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2001.04329.x
Subject(s) - physics , cooling flow , luminous infrared galaxy , astrophysics , infrared , galaxy , spectral line , cosmic infrared background , astronomy , flow (mathematics) , optics , mechanics , cosmic microwave background , anisotropy
We have taken K ‐band spectra covering seven cooling flow clusters. The spectra show many of the 1‐0S transitions of molecular hydrogen, as well as some of the higher vibrational transitions, and some lines of ionized hydrogen. The line ratios allow us to conclude that the rotational states of the first excited vibrational state are in approximate local thermodynamic equilibrium (LTE), so that densities above 10 5 cm −3 are likely, but there is evidence that the higher vibrational states are not in LTE. The lack of pressure balance between the molecular gas and the ionized components emphasizes the need for dynamic models of the gas. The ratios of the ionized to molecular lines are relatively constant but lower than from starburst regions, indicating that alternative heating mechanisms are necessary.