The origin of star formation since z=1
Abstract
The use of multiple integral field units with FLAMES/GIRAFFE at VLT has revolutionized investigations of distant galaxy kinematics. This facility may recover the velocity fields of almost all emission line galaxies with I(AB)<22.5 at z<0.8. We have gathered a unique sample of 63 velocity fields at z=0.4-0.75, which are representative of Mstellar > 1.5*1010 Msun emission line W0([OII])>15 galaxies, and are unaffected by cosmic variance. Taking into account all galaxies -with or without emission lines- in that redshift range, we find that 42+/-7% of them have anomalous kinematics, including 26+/-7% with complex kinematics, i.e. not supported by either rotation or by dispersion. The large fraction of complex velocity fields suggests a large impact of merging in shaping the galaxies in the intermediate mass range. We discuss how this can be accommodated within the frame of current scenarios of galaxy formation, including for the Milky Way and M31.
Turn this paper into a lesson
ArcXiv compiles a structured reading guide from this paper's metadata: plain-English importance, contributions, prerequisite concepts, which sections to read first, flashcards, and a quiz. Grounded in the abstract, never invented.