Flares, Warps, Truncations, and Satellite: The Ultra-thin Galaxy UGC 11859

Ossa-Fuentes, Luis; Borlaff, Alejandro S.; Beckman, John E.; Marcum, Pamela M.; Fanelli, Michael N.
Referencia bibliográfica

The Astrophysical Journal

Fecha de publicación:
7
2023
Número de autores
5
Número de autores del IAC
1
Número de citas
3
Número de citas referidas
1
Descripción
The structure of the outskirts of galaxies provides valuable information about their past and evolution. Due to their projected orientation, edge-on isolated galaxies effectively serve as test labs in which to study the three-dimensional structures of galaxies, including warps and flares, and to explore the possible sources of such distortions. We analyzed the structure of the apparently isolated edge-on ultra-thin galaxy UGC 11859 to look for the presence of distortions. The deep optical imaging observations ( ${\mu }_{\mathrm{lim}}=30.6$ and 30.0 $\mathrm{mag}\ {\mathrm{arcsec}}^{-2}$ in the g- and r-bands, respectively) we acquired with the 10.4 m Gran Telescopio Canarias are used to derive the radial and vertical surface brightness profiles and g - r color radial profile. We find that UGC 11859's disk displays a significant gravitational distortion. A warp is clearly detected on one side of the disk, and the galactic plane on both sides of the center shows increasing scale height with an increasing galactocentric radius, indicating the presence of a flare in the stellar distribution. The surface brightness profile of the disk shows a sharp break at 24 kpc galactocentric radius, and a steep decline to larger radii, an "edge-on truncation," which we associate with the presence of the flare. The present study is the first observational support for a connection between truncations and flares. Just beyond the warped side of the disk, a faint galaxy is observed within a small angular distance, identified as a potential interacting companion. Based on ultradeep g and r photometry we estimate that if the potential companion is at the same distance as UGC 11859, the stellar mass of the satellite galaxy is log10(M ⊙) = ${6.33}_{-0.02}^{+0.02}$ .
Proyectos relacionados
Project Image
Las Galaxias Espirales: Evolución y Consecuencias
Nuestro grupo pequeño esta bien conocido y respetado internacionalmente por nuestro trabajo inovativo e importante en varios aspectos de la estructura y la evolución de las galaxias espirales cercanas. Usamos principalmente observaciones en varias longitudes de onda, explotando las sinergías que nos permiten responder a las cuestiones más
Johan Hendrik
Knapen Koelstra