Detalles de publicación
PP 011063
Resonant structure in the disks of spiral galaxies, using phase-reversals in streaming motions from 2D Hα Fabry-Perot spectroscopy
1. Instituto de Astrofísica de Canarias 2. Departamento de Astrofísica, ULL.
3. CSIC 4. Laboratoire d’Astrophysique de Toulouse-Tarbes. Université de Toulouse, CNRS 5. CNRS, IRAP 7. Oscar Klein Centre for Cosmoparticle Physics, Stockholm University 8. Instituto de Astronomía, UNAM, Ensenda. 9. Département de Physique et Astronomie, Université de Montreal,
In this article we introduce a technique for finding resonance radii in a disk galaxy. We
use a two-dimensional velocity field in Hα emission obtained with Fabry-Perot
interferometry, derive the classical rotation curve, and subtract it off, leaving a residual
velocity map. As the streaming motions should reverse sign at corotation, we detect
these reversals, and plot them in a histogram against galactocentric radius, excluding
points where the amplitude of the reversal is smaller than the measurement uncertainty.
The histograms show well-defined peaks which we assume to occur at resonance radii,
identifying corotations as the most prominent peaks corresponding to the relevant
morphological features of the galaxy (notably bars and spiral arm systems). We
compare our results with published measurements on the same galaxies using other
methods and different types of data.
use a two-dimensional velocity field in Hα emission obtained with Fabry-Perot
interferometry, derive the classical rotation curve, and subtract it off, leaving a residual
velocity map. As the streaming motions should reverse sign at corotation, we detect
these reversals, and plot them in a histogram against galactocentric radius, excluding
points where the amplitude of the reversal is smaller than the measurement uncertainty.
The histograms show well-defined peaks which we assume to occur at resonance radii,
identifying corotations as the most prominent peaks corresponding to the relevant
morphological features of the galaxy (notably bars and spiral arm systems). We
compare our results with published measurements on the same galaxies using other
methods and different types of data.