We measure the strength, frequency, and timescale of tidally triggered star formation at redshift z = 0.08-0.38 in a spectroscopically complete sample of galaxy pairs drawn from the magnitude-limited redshift survey of 9825 Smithsonian Hectospec Lensing Survey galaxies with R 20.3. To examine the evidence for tidal triggering, we identify a volume-limited sample of major (|螖MR | 1.75, corresponding to mass ratio 1/5) pair galaxies with MR 鈥?0.8 in the redshift range z = 0.08-0.31. The size and completeness of the spectroscopic survey allow us to focus on regions of low local density. The spectrophotometric calibration enables the use of the 4000 脜 break (Dn 4000), the H伪 specific star formation rate (SSFRH伪), and population models to characterize the galaxies. We show that Dn 4000 is a useful population classification tool; it closely tracks the identification of emission line galaxies. The sample of major pair galaxies in regions of low local density with low Dn 4000 demonstrates the expected anti-correlation between pairwise projected separation and a set of star formation indicators explored in previous studies. We measure the frequency of triggered star formation by comparing the SSFRH伪 in the volume-limited sample in regions of low local density: 32% 卤 7% of the major pair galaxies have SSFRH伪 at least double the median rate of the unpaired field galaxies. Comparison of stellar population models for pair and for unpaired field galaxies implies a timescale for triggered star formation of ~300-400聽Myr.
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