|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'504'928
Articles rated: 2609
25 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
The orientation parameters and rotation curves of 15 spiral galaxies | | A.M. Fridman
; V.L.Afanasiev
; S.N. Dodonov
; O.V. Khoruzhii
; A.V.Moiseev
; O.K. Sil’chenko
; A.V.Zasov
; | | Date: |
27 Sep 2004 | | Subject: | astro-ph | | Affiliation: | 1,2), V.L.Afanasiev , S.N. Dodonov , O.V. Khoruzhii (1,4), A.V.Moiseev (3,5), O.K. Sil’chenko (2,6), A.V.Zasov ( Institute of Astronomy of the Russian Academy of Science, Sternberg Astronomical Institute, Special Astrophysical Observatory, Tr | | Abstract: | We analyzed ionized gas motion and disk orientation parameters for 15 spiral galaxies. Their velocity fields were measured with the H-alpha emission line by using the Fabry-Perot interferometer at the 6m telescope of SAO RAS. Special attention is paid to the problem of estimating the position angle of the major axis (PA_0) and the inclination (i) of a disk, which strongly affect the derived circular rotation velocity. We discuss and compare different methods of obtaining these parameters from kinematic and photometric observations, taking into account the presence of regular velocity (brightness) perturbations caused by spiral density waves. It is shown that the commonly used method of tilted rings may lead to systematic errors in the estimation of orientation parameters (and hence of circular velocity) being applied to galaxies with an ordered spiral structure. Instead we recommend using an assumption of constancy of i and PA_0 along a radius, to estimate these parameters. For each galaxy of our sample we present monochromatic H-alpha- and continuum maps, velocity fields of ionized gas, and the mean rotation curves in the frame of a model of pure circular gas motion. Significant deviations from circular motion with amplitudes of several tens of km/s (or higher) are found in almost all galaxies. The character and possible nature of the non-circular motion are briefly discussed. | | Source: | arXiv, astro-ph/0409622 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER