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Triggering star formation by galaxy-galaxy interactions

Patricia B. Tissera·Diego G. Lambas·M. Sol Alonso·Georgina Coldwell
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Abstract

We analyzed the effects of having a close companion on the star formation activity of galaxies in 8K galaxy pair catalog selected from the 2dFGRS. We found that, statistically, galaxies with $r_{\rm p} < 25 {\rm h^{-1}}$ kpc and $ΔV < 100 {\rm km/s}$ have enhanced star formation with respect to isolated galaxies with the same luminosity and redshift distribution. Our results suggest that the physical processes at work during tidal interactions can overcome the effects of environment, expect in dense regions.

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Patricia B. Tissera, Diego G. Lambas, M. Sol Alonso, Georgina Coldwell. 2003-10-20. Triggering star formation by galaxy-galaxy interactions. https://arxiv.org/abs/astro-ph/0310560

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