FM 047-02: a collisional pair of galaxies with a ring

Abstract

Aims. We investigate the nature of the galaxy pair FM 047-02, which has been proposed as an archetype of the Solitaire types of peculiar (collisional) ring galaxies. Methods. The study is based on long-slit spectrophotometric data in the range of 3500-9500 Å obtained with the Gemini Multi-Object Spectrograph at Gemini South (GMOS-S). The absorption spectra were used to determine the radial velocity. The stellar population synthesis code STARLIGHT was used to investigate the star formation history of the galaxy pair FM 047-02. Results. During the whole long-slit signal, the spectra of both galaxies resemble those of an early-type galaxy. Both objects are dominated by an old stellar population of 2 × 10 9 < t ≤ 13 × 10 9 yr and a small, but a non-negligible fraction (about 13%) of young stars of t ≤ 5 × 10 7 yr are estimated to contribute to the optical flux for NED02. Both observed small radial-velocity differences, and the structures around NED01 suggest an ongoing tidal interaction of both galaxies. Conclusions. The spectroscopic results and the morphological peculiarities of NED01 can be adequately interpreted as continuing off-center stage of interaction with the companion galaxy NED02. The core of NED01 and NED02 are in counter-rotating motion. The visual appearance of NED01, its kinematical properties, the smooth distribution of material in the ring, and its off-centered nucleus, characterize it as a true archetype of a Solitaire-type ring galaxy in an advanced stage of ring formation.

Visiting two objects in the field of the ring galaxy HRG 2302

“…Even though both H and I bulges are round, one sees that (i) the galaxy halo of I is elliptical-like; (ii) its major axis lies almost perpendicular to the minor axis of the H galaxy; (iii) the external R-band isophotes of H are boxy; (iv) the luminous nuclei do not lie on the geometrical centers of their respective bulge isophotes, but are slightly displaced one toward the other. This behavior can also be seen in peculiar ring galaxies of Solitaire type in early stages of interaction (see Wenderoth et al 2011) and ongoing tidal interaction (see Faúndez-Abans et al 2013).…”

“…This code is extensively discussed in Cid Fernandes et al (2004Fernandes et al ( , 2005, and it is built upon computational techniques that originally were developed for empirical population synthesis with additional ingredients from evolutionary synthesis models. This method was used by Krabbe et al (2011) and Faúndez-Abans et al (2012, 2013 and has been successful in describing the stellar population in interacting galaxies. Briefly, the code fits an observed spectrum with a combination of N single stellar populations (SSPs) from the models of Bruzual & Charlot (2003).…”

Estudo da Atividade Nuclear e População Estelar na Galáxia Peculiar AM 0004-413 (ESO 293-IG 037)

“…A curva de rotação obtida revela um formato U, interpretada na literatura como um indicador de interação gravitacional [22][23][24][25][26], visto em galáxias elípticas perturbadas binárias em interação [23,27,28], e em alguns pares Sb de galáxias peculiares como RR 24 [29].…”

Estudo Espectroscópico do Par de Galáxias Interagentes ESO 505-IG 030 e ESO 505-IG 031

“…Atualmente, o valoré consideravelmente menor, 68±2 km/s/Mpc [34]. Nesse estudo, usamos o valor de 73 km/s/Mpc, já empregado em outros estudos do nosso grupo de pesquisa [35][36][37][38][39][40][41].…”