The merger history of massive spheroids since z ˜ 1 is size-independent

Díaz-García, L. A.; Mármol-Queraltó, E.; Trujillo, I.; Cenarro, A. J.; López-Sanjuan, C.; Pérez-González, P. G.; Barro, G.
Bibliographical reference

Monthly Notices of the Royal Astronomical Society, Volume 433, Issue 1, p.60-68

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7
2013
Number of authors
7
IAC number of authors
2
Citations
6
Refereed citations
6
Description
Using a compilation of 379 massive (stellar mass M ≳ 1011 M⊙) spheroid-like galaxies from the near-infrared Palomar/DEEP-2 survey, we investigated, up to z ˜ 1, whether the presence of companions depends on the size of the host galaxy. We explored the presence of companions for mass ratios with respect to the central massive galaxy down to 1 : 10 and 1 : 100, and within projected distances of 30, 50 and 100 kpc of these objects. We found evidence that these companions are equally distributed around both compact and extended massive spheroid-like galaxies. This suggests that, at least since z ˜ 1, the merger activity in these objects is nearly homogeneous across the whole population and that the merger history is not affected by the size of the host galaxy. Our results could indicate that compact and extended massive spheroid-like galaxies are increasing in size at the same rate.
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Traces of Galaxy Formation: Stellar populations, Dynamics and Morphology
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