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Nonbarred ringed galaxies are relatively normal galaxies showing bright ringsof star formation in spite of lacking a strong bar. This morphology isinteresting because it is generally accepted that a typical ring forms whenmaterial collects near a resonance, set up by the pattern speed of a bar orbar-like perturbation. Our goal in this paper is to examine whether the ringstar formation properties are related to the non-axisymmetric gravity potentialin general. For this purpose, we obtained H{\alpha} emission line images andcalculated the line fluxes and star formation rates (SFRs) for 16 nonbarred SAgalaxies and four weakly barred SAB galaxies with rings. For comparison, wecombine our observations with a re-analysis of previously published data onfive SA, seven SAB, and 15 SB galaxies with rings, three of which areduplicates from our sample. With these data, we examine what role a bar mayplay in the star formation process in rings. Compared to barred ringedgalaxies, we find that the inner ring SFRs and H{\alpha}+[N ii] equivalentwidths in nonbarred ringed galaxies show a similar range and trend withabsolute blue magnitude, revised Hubble type, and other parameters. On thewhole, the star formation properties of inner rings, excluding the distributionof H ii regions, are independent of the ring shapes and the bar strength in oursmall samples. We confirm that the deprojected axis ratios of inner ringscorrelate with maximum relative gravitational force Q_g; however, if weconsider all rings, a better correlation is found when local bar forcing at theradius of the ring, Q_r, is used. Individual cases are described and othercorrelations are discussed. By studying the physical properties of thesegalaxies, we hope to gain a better understanding of their placement in thescheme of the Hubble sequence and how they formed rings without the drivingforce of a bar.

Ring Star Formation Rates in Barred and Nonbarred Galaxies