Topology of non-linear structure in the 2dF Galaxy Redshift Survey
| dc.creator | James, J. Berian | |
| dc.creator | Colless, Matthew | |
| dc.creator | Lewis, Geraint F. | |
| dc.creator | Peacock, John A. | |
| dc.date | 2008-10-12 | |
| dc.date | 2009-03-13 | |
| dc.date.accessioned | 2026-07-07T12:51:46Z | |
| dc.date.available | 2026-07-07T12:51:46Z | |
| dc.description | We study the evolution of non-linear structure as a function of scale in samples from the 2dF Galaxy Redshift Survey, constituting over 221 000 galaxies at a median redshift of z=0.11. The two flux-limited galaxy samples, located near the southern galactic pole and the galactic equator, are smoothed with Gaussian filters of width ranging from 5 to 8 Mpc/h to produce a continuous galaxy density field. The topological genus statistic is used to measure the relative abundance of overdense clusters to void regions at each scale; these results are compared to the predictions of analytic theory, in the form of the genus statistic for i) the linear regime case of a Gaussian random field; and ii) a first-order perturbative expansion of the weakly non-linear evolved field. The measurements demonstrate a statistically significant detection of an asymmetry in the genus statistic between regions corresponding to low- and high-density volumes of the universe. We attribute the asymmetry to the non-linear effects of gravitational evolution and biased galaxy formation, and demonstrate that these effects evolve as a function of scale. We find that neither analytic prescription satisfactorily reproduces the measurements, though the weakly non-linear theory yields substantially better results in some cases, and we discuss the potential explanations for this result. | |
| dc.description | 13 pages, matching proof to be published in MNRAS; new version adds reference and corrects figure 6 | |
| dc.identifier | https://arxiv.org/abs/0810.2115 | |
| dc.identifier | http://arxiv.org/abs/0810.2115 | |
| dc.identifier | Mon. Not. R. Astron. Soc. (2009) 394, 454-466 | |
| dc.identifier | doi:10.1111/j.1365-2966.2008.14358.x | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/223097 | |
| dc.subject | Astrophysics | |
| dc.title | Topology of non-linear structure in the 2dF Galaxy Redshift Survey | |
| dc.type | text |