**Publication date:** Nov 2017

**Abstract:**

In our previous work (Paper I) we applied several models of high-

frequency quasi-periodic oscillations (HF QPOs) to estimate the spin of

the central compact object in three Galactic microquasars assuming the

possibility that the central compact body is a super-spinning object (or

a naked singularity) with external spacetime described by Kerr geometry

with a dimensionless spin parameter a ≡ cJ/GM^{2} > 1. Here

we extend our consideration, and in a consistent way investigate

implications of a set of ten resonance models so far discussed only in

the context of a < 1. The same physical arguments as in Paper I are

applied to these models, I.e. only a small deviation of the spin

estimate from a = 1, a ≳ 1, is assumed for a favoured model. For five of

these models that involve Keplerian and radial epicyclic oscillations we

find the existence of a unique specific QPO excitation radius.

Consequently, there is a simple behaviour of dimensionless frequency M ×

ν_{U}(a) represented by a single continuous function having

solely one maximum close to a ≳ 1. Only one of these models is

compatible with the expectation of a ≳ 1. The other five models that

involve the radial and vertical epicyclic oscillations imply the

existence of multiple resonant radii. This signifies a more complicated

behaviour of M × ν_{U}(a) that cannot be represented by single

functions. Each of these five models is compatible with the expectation

of a ≳ 1.

**Authors:**

Kotrlová, A.; Šrámková, E.; Török, G.; Stuchlík, Z.; Goluchová, K.;