Galaxy interactions increase star formation rates

Knapen, J. H.; Cisternas, M.; Querejeta, M.
Referencia bibliográfica

Highlights of Spanish Astrophysics VIII, Proceedings of the XI Scientific Meeting of the Spanish Astronomical Society held on September 8-12, 2014, in Teruel, Spain, ISBN 978-84-606-8760-3. A. J. Cenarro, F. Figueras, C. Hernández-Monteagudo, J. Trujillo Bueno, and L. Valdivielso (eds.), p. 240-244

Fecha de publicación:
5
2015
Número de autores
3
Número de autores del IAC
2
Número de citas
0
Número de citas referidas
0
Descripción
We investigate the influence of galaxy-galaxy interactions on the star formation by studying a sample of almost 1500 of the nearest galaxies, all within a distance of 40 Mpc. We calculate the relative enhancement of the massive star formation rate (SFR), as measured from far-IR emission, and the specific star formation rate (SSFR), which is the former quantity normalised by the stellar mass of the galaxy. We do this for each galaxy by normalising by the median SFR and SSFR values of individual control populations of similar non-interacting galaxies. We find that both the SFR and the SSFR are enhanced in interacting galaxies, and more so as the degree of interaction is higher. The increase is, however, moderate, reaching a maximum of a factor of 2.2 for the highest degree of interaction (mergers). We argue that this study based on a representative sample of nearby galaxies should be used to place strong constraints on studies based on samples of galaxies at larger distances, beyond the local Universe.