Austrian Early Career Conference 2024

Contribution:
Talk

Authors:
Jan-Niklas Pippert

Affiliations:
Max Planck Institute for Extraterrestrial Physics

Title:
Extragalactic Stream Models based on 1D Gaussian Slices

Abstract:
From the ΛCDM paradigm it is expected that galaxies merge and grow in extreme and violent environments. These processes form tidal features of various shapes and properties depending on the merger mass ratio, orbital parameters, and gas richness. We use 170 archival g' band observations of local (z ≤ 0.08) galaxy clusters, captured with the Wendelstein Wide Field Imager (WWFI) to identify tidal features around galaxies in these fields. Of the features that were discovered, 15 have been selected for more detailed photometric studies. A fast and innovative technique was developed for determining the photometric characteristics of tidal streams and tails. It utilizes a Gaussian distribution with higher-order moments to describe the light profile of such features perpendicular to their elongation direction. Apertures are generated directly from a FWHM criterion. It can be utilized for large samples, which are produced by upcoming surveys, e.g., EUCLID (not only for low but perhaps for higher redshifts). The deep Wendelstein images allow measuring the surface brightnesses inside one FHWM down to ~27 g' mag arcsec⁻² . The streams have on average ~26.1 g' mag arcsec⁻² and are dimmer than the tails in our sample (~25.2 g' mag arcsec⁻²). Structural parameters, such as the effective radius Re and the effective surface brightness µe are compared to various galaxy types. From that, we suggest, from our small sample size, that streams originate most likely from ellipticals and spirals, whereas dwarfs are excluded due to their faintness.