The gas kinematics of galaxies in a Lambda-CDM Universe

DE ROSSI, MARÍA EMILIA; TISSERA, PATRICIA BEATRIZ; PEDROSA, SUSANA ELIZABETH

Ciudad Autónoma de Buenos Aires

Workshop; New Frontiers in Relativistic and Numerical Astrophysics Workshop; 2012

Grupo de Astrofísica Numérica del IAFE y Grupo de Astrofísica Relativista y Radio Astronomía del IAR

We studied the evolution of the gas kinematics of galaxies by performing hydrodynamical simulations in a cosmological scenario. We payed particular attention to the origin of the scatter of the Tully-Fisher Relation and the features which could be associated to mergers and interactions. We extended the study by De Rossi et al. (2010) and analysed their whole simulated sample which includes both, gas disc-dominated and spheroid-dominated systems. We found that mergers and interactions can affect the rotation curves directly or indirectly inducing a scatter in the Tully-Fisher Relation larger than the simulated evolution since z=3. In agreement with previous works, kinematic indicators which combine the rotation velocity and dispersion velocity in their definitions lead to a tighter relation. In addition, when we estimate the rotation velocity at the maximum of the rotation curve, we obtain the best proxy for the potential well regardless of morphology.