RESONANT STRUCTURE IN THE DISKS OF SPIRAL GALAXIES, USING PHASE REVERSALS IN STREAMING MOTIONS FROM TWO-DIMENSIONAL H alpha FABRY-PEROT SPECTROSCOPY
2011 (English)In: The Astrophysical Journal Letters, ISSN 2041-8205, Vol. 741, no 1, L14- p.Article in journal (Refereed) Published
In this Letter, we introduce a technique for finding resonance radii in a disk galaxy. We use a two-dimensional velocity field in H alpha 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.
Place, publisher, year, edition, pages
2011. Vol. 741, no 1, L14- p.
galaxies: fundamental parameters, galaxies: kinematics and dynamics, galaxies: spiral, techniques: interferometric
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:su:diva-70890DOI: 10.1088/2041-8205/741/1/L14ISI: 000296753000014OAI: oai:DiVA.org:su-70890DiVA: diva2:483382
authorCount :62012-01-252012-01-242012-01-25Bibliographically approved