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Star Formation Enhancement in Barred Disk Galaxies in Interacting Galaxy Clusters

A recent study shows that bars can be induced via interaction of galaxy clusters, but it has been unclear if the bar formation by the interaction between clusters is related to the enhancement of star formation. We study galaxies in 105 galaxy clusters at $0.015<z<0.060$ detected from Sloan Digital Sky Survey data, in order to examine whether the fraction of star-forming galaxies ($f_\mathrm{sf}$) in 16 interacting clusters is enhanced compared with that of the other non-interacting clusters and to investigate the possible connection between the $f_\mathrm{sf}$ enhancement and the bar formation in interacting clusters. We find that $f_\mathrm{sf}$ is moderately higher ($\sim20\%$) in interacting clusters than in non-interacting clusters and that the enhancement of star formation in interacting clusters occurs only in moderate-mass disk-dominated galaxies ($10^{10.0} \le M_\mathrm{star}/M_{\odot} < 10^{10.4}$ and the bulge-to-total light ratio is $\le0.5$). We also find that the enhancement of $f_\mathrm{sf}$ in moderate-mass disk-dominated galaxies in interacting clusters is mostly due to the increase of the number of barred galaxies. Our result suggests that the cluster-cluster interaction can simultaneously induce bars and star formation in disk galaxies.