Interaction-induced star formation in a complete sample of 105 nearby star-forming galaxies

By Cheng Li, G. Kauffmann, T. Heckman, Yipeng Jing, Simon D. M. White. 2007

138 citations recorded by the source corpus.

We investigate the clustering properties of a complete sample of 10 5 star-forming galaxies drawn from the data release 4 (DR4) of the Sloan Digital Sky Survey. On scales less than 100 kpc, the amplitude of the correlation function exhibits a strong dependence on the specific star formation rate (SSFR) of the galaxy. We interpret this as the signature of enhanced star formation induced by tidal interactions. We then explore how the average star formation rate (SFR) in a galaxy is enhanced as the projected separation rp between the galaxy and its companions decreases. We find that the enhancement strongly depends on rp, but very weakly on the relative luminosity of the companions. The enhancement is also stronger in low-mass galaxies than in high-mass galaxies. In order to explore whether a tidal interaction is not only sufficient, but also necessary to trigger enhanced star formation in a galaxy, we compute background subtracted neighbour counts for the galaxies in our sample. The average number of close neighbours around galaxies with low to average values of SFR/M∗ is close to zero. At the highest SSFRs, however, more than 40 per cent of the galaxies in our sample have a companion within a projected radius of 100 kpc. Visual inspection of the highest SFR/M∗ galaxies without companions reveals that more than 50 per cent of these are clear interacting or merging systems. We conclude that tidal interactions are the dominant trigger of enhanced star formation in the most strongly star-forming systems. Finally, we find clear evidence that tidal interactions not only lead to enhanced star formation in galaxies, but also cause structural changes such as an increase in concentration.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/c9d3ac65935ffc01d2ee18d39dbafa0cb5ad6b7c

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Citations in the corpus

FEEDBACK FROM CENTRAL BLACK HOLES IN ELLIPTICAL GALAXIES. III. MODELS WITH BOTH RADIATIVE AND MECHANICAL FEEDBACK (2010, result): “We note that the possibility of QSO activity even in absence of merging, has also been recently proposed also by others (e.g., Li et al. 2008, Kauffmann & Heckman 2009, Tal et al. 2009).”
Galaxy pairs in the Sloan Digital Sky Survey – VIII. The observational properties of post-merger galaxies (2013, background): “…Alonso et al. 2012; Lambas et al. 2012), star formation rates (Nikolic, Cullen & Alexander 2004; Alonso et al. 2006; Ellison et al. 2008, 2013; Li et al 2008a; Scudder et al. 2012b; Patton et al. 2013), metallicity (Michel-Dansac et al. 2008; Ellison et al. 2008; Reichard et al. 2009; Peeples…”
A calibration of the relation between the abundance of close galaxy pairs and the rate of galaxy mergers (2008, background): “Many authors, beginning with Toomre & Toomre (1972) and Larson & Tinsley (1978) have shown that close encounters between massive galaxies can produce both enhanced star formation and disturbed morphologies (e.g. Patton et al. 2005; Lin et al. 2007; Li et al. 2008, and references therein).”
The Sydney-AAO Multi-object Integral field spectrograph (2011, background): “Traditionally, in large galaxy surveys, the association of activity and dynamical disturbances is made from the proximity of galaxies in position and redshift space (e.g. Nikolic, Cullen & Alexander 2004; Li et al. 2008a).”
Galaxy pairs in the Sloan Digital Sky Survey – II. The effect of environment on interactions (2010, background): “A number of works have previously found that galaxies with a close companion have higher central concentrations (e.g. Nikolic et al. 2004; Li et al. 2008).”
Galaxy pairs in the Sloan Digital Sky Survey – V. Tracing changes in star formation rate and metallicity out to separations of 80 kpc (2012, background): “Galaxies in pairs show enhanced SFRs out to separations of ∼ 30 h−170 kpc, with the strongest enhancement at the smallest separations, and a smooth decline to a fiducial value (Lambas et al. 2003; Alonso et al. 2006; Nikolic et al. 2004; Ellison et al. 2008b; Li et al. 2008).”
THE GREATER IMPACT OF MERGERS ON THE GROWTH OF MASSIVE GALAXIES: IMPLICATIONS FOR MASS ASSEMBLY AND EVOLUTION SINCE z ≃ 1 (2009, result): “A similar conclusion was reached by Li et al. (2008) using SDSS.”
Galaxy merger morphologies and time-scales from simulations of equal-mass gas-rich disc mergers (2008, background): “…separation and line-of-sight radial velocity (e.g. Patton et al. 2000; Barton, Geller, & Kenyon 2000; Lin et al. 2004; de Propris et al. 2005; Lin et al. 2008) or by measuring the deprojected correlation function on small scales (Bell et al. 2006a; Masjedi et al. 2006, 2008; Li et al. 2008).”