Correlating galaxy shapes and initial conditions: observational study [CEA]

http://arxiv.org/abs/2111.12578


We find that galaxy angular momenta determined from shapes of spiral galaxies correlate with the initial tidal field in the galaxy’s neighborhood. Explicitly, we find that the galaxies tend to be preferentially face on (edge on) oriented when the major (minor) axis of the initial tidal field is aligned with the line of sight. Because tidal-torque theory predicts vanishing of this kind of signal, the observed correlation suggests non-linear origin. This correlation is statistically significant even after considering the number of observables investigated. Our result provides motivation for considering galaxy shape information in the efforts aiming to reconstruct initial conditions in the Universe.

Read this paper on arXiv…

P. Motloch, U. Pen and H. Yu
Thu, 25 Nov 21
57/60

Comments: 8 pages, 3 figures