Year: 2012
Type: article
Abstract: The ultraviolet and far-ultraviolet spectra of HD 147888 allows the H2 vibrational level ν = 0 to be accessed along with higher vibrational levels of the ground H2 electronic level. The large number of H2 absorption lines in the HST spectra allows column densities to be determined even from a noisy spectra. We have determined column densities of the H2 molecule on vibrational levels ν = 0–5 and rotational levels J = 0–6 using the profile fitting method. No variations in the column densities of H2 on vibrationally excited levels were observed from 2000 through 2009. The ortho to para H2 ratio (O/P)* for the excited vibrational states ν = 1–4 equals to 1.13. For the lowest vibrational state ν = 0 and rotational level J = 1 the ortho to para H2 ratio is only 0.15. The temperature of ortho-para thermodynamical equilibrium is TOP = 42 ± 3 K.
Source: Astronomy and Astrophysics
Author: P. Gnaciński
Institution: University of Gdańsk
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2593083174