Circumnuclear rings and Lindblad resonances in spiral galaxies
  In order to study the location of circumnuclear rings (CNR) and their
possible relation with the inner Lindblad resonances (ILR), we investigate a
sample of spiral galaxies. For this purpose, we have obtained and analyzed
medium resolution spectra of 5 spiral galaxies in the range 6200 \AA \ to 6900
\AA.\, Through the H$\alpha$ emission line, we constructed the radial velocity
curves, and then the rotation curves. By fitting them, considering two or three
components of an axisymetric Miyamoto$-$Nagai gravitational potential, we
constructed the angular velocity and Lindblad curves. In addition, we
determined the CNR radius by using the 2D spectra and generating the H$\alpha$
spatial emission radial profiles. We determined the position of the resonances
and we calculated the angular velocity pattern, which are in the range of 26
$-$ 47 km s$^{-1}$ kpc$^{-1}$ for the galaxies of the sample. According to our
results, the CNRs are located between the inner ILR (iILR) and the outer ILR
(oILR), or between the center of the galaxy and the ILR, when the object has
only one of such resonance; in agreement with previous results. In addition, we
calculated the dimensionless parameter defined as $\mathcal{R}=$ R$_{CR}$ /
R$_{bar}$, being in the range 1.1 $-$ 1.6, in agreement with previous results
found in the literature.
