Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The orientation of disk galaxies around large cosmic voids   Using a large sample of galaxies from the SDSS-DR7, we have analysed the
alignment of disk galaxies around cosmic voids. We have constructed a complete
sample of cosmic voids (devoid of galaxies brighter than M_r-5 log(h) =-20.17)
with radii larger than 10 Mpc/h up to redshift 0.12. Disk galaxies in shells
around these voids have been used to look for particular alignments between the
angular momentum of the galaxies and the radial direction of the voids. We find
that disk galaxies around voids larger than >~ 15 Mpc/h within distances not
much larger than 5 Mpc/h from the surface of the voids present a significant
tendency to have their angular momenta aligned with the void's radial direction
with a significance >~ 98.8% against the null hypothesis. The strength of this
alignment is dependent on the void's radius and for voids with ~<15 Mpc/h the
distribution of the orientation of the galaxies is compatible with a random
distribution. Finally, we find that this trend observed in the alignment of
galaxies is similar to the one observed for the minor axis of dark matter halos
around cosmic voids found in cosmological simulations, suggesting a possible
link in the evolution of both components.

20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph