Aims. We report first results of an investigation of the tidally disturbed galaxy system AM 546-324, whose two principal galaxies 2MFGC 04711 and AM 0546-324 (NED02) were previously classified as interacting doubles. This system was selected to study the interaction of ellipticals in a moderately dense environment. We provide spectral characteristics of the system and present an observational study of the interaction effects on the morphology, kinematics, and stellar population of these galaxies. Methods. The study is based on long-slit spectrophotometric data in the range of ∼4500−8000 Å obtained with the Gemini MultiObject Spetrograph at Gemini South (GMOS-S). We have used the stellar population synthesis code STARLIGHT to investigate the star formation history of these galaxies. The Gemini/GMOS-S direct r-G0303 broad band pointing image was used to enhance and study fine morphological structures. The main absorption lines in the spectra were used to determine the radial velocity. Results. Along the whole long-slit signal, the spectra of the Shadowy galaxy (discovered by us), 2MFGC 04711, and AM 0546-324 (NED02) resemble that of an early-type galaxy. We estimated redshifts of z = 0.0696, z = 0.0693 and z = 0.0718, corresponding to heliocentric velocities of 20 141 km s −1 , 20 057 km s −1 , and 20 754 km s −1 for the Shadowy galaxy, 2MFGC 04711 and AM 0546-324 (NED02), respectively. The central regions of 2MFGC 04711 and AM 0546-324 (NED02) are completely dominated by an old stellar population of 2 × 10 9 < t ≤ 13 × 10 9 yr and do not show any spatial variation in the contribution of the stellar-population components. Conclusions. The observed rotation profile distribution of 2MFGC 04711 and AM 0546-324 (NED02) can be adequately interpreted as an ongoing stage of interaction with the Shadowy galaxy as the center of the local gravitational potential-well of the system. The three galaxies are all early-type. The extended and smooth distribution of the material in the Shadowy galaxy is a good laboratory to study direct observational signatures of tidal friction in action.

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.

Aims. We investigate the nature of two galaxies that are located in the field of the ring galaxy HRG 2302. Methods. This study is based on direct BVRI imaging and long-slit spectrophotometric data in the range of 4000−9500 Å obtained with the 1.6 m telescope of the Observatório do Pico dos Dias, Brazil. The spectra were used to determine the radial velocity. Results. The primary objective of the retrieval of the photometric data was to identify the fine structures of objects H and I. In addition, we performed image processing and made a photometric analysis to obtain the integrated standard BVRI magnitudes. The contour maps show evidence of material connecting both galaxies, suggesting that they might be interacting close companions. We estimated redshifts of z = 0.0689 and z = 0.0692. The spectra of the two galaxies resemble those of an early-type galaxy. The fact that the objects have a small radial-velocity difference and the structures around object I suggest an ongoing tidal interaction between the two galaxies. Conclusions. The H-I system seems to be composed of two early-type spiral galaxies (S0/Sa). Galaxy I shows evidence of tidal perturbation: an off-centered bulge, some material extending along the NE direction, and structures that have been enhanced by image filtering procedures. There are some dwarf objects around it. Neither object shows evidence of nuclear activity.

ABSTRACT This contribution aims to study the nature (kinematic, nuclear activity, and stellar population) of a sample of 10 galaxies in the poor cluster Abell S0805. As no detailed optical spectroscopy for some members has been published yet, the selected sample makes this study ideal for investigating the properties of the following objects: ESO 104- G(002, 006, 007, 008, 009, 010, 013), Fairall 0187, and PGC (062384, 062391). Our main results were obtained after subtraction of the underlying stellar population with the spectral synthesis code starlight. The residual spectra reveal seven galaxies with only absorption lines [ESO 104- G(002, 007, 008, 009), Fairall 0187 and PGC (062384, 062391)], and three galaxies with emission lines [ESO 104- G(006, 010, 013)]. According to the boundaries in the diagnostic diagrams, the intensities of H α and the low-ionization lines ([N ii] λ6584 Å and [S ii] λλ6716,6731 Å) suggest the following results: (i) the brightest cluster galaxy (ESO 104- G006, an elliptical cD galaxy) shows low-ionization nuclear emission-line region (LINER)-like excitation, quite common in ‘cool core clusters’; (ii) the ESO 104- G010 (‘X-Galaxy’ or ‘Crystal Frog’) shows an excess of the nitrogen emission-line [N ii] λ6584 Å not yet reported. We also suggest this object as a LINER; (iii) the spiral ESO 104- G013 is a star-forming galaxy with typical emission lines. No obvious signs of interaction were observed in this study. The heliocentric velocities agree within 1σ with the most recent values. The stellar population, rotation curves, and velocity dispersions are also discussed for the first time for some objects.

We present the first spectroscopic observations for the galaxies ESO 089−G018 (hereafter G18, an Sb(?)‐type galaxy seen nearly edge‐on) and ESO 089−G019 (hereafter G19, an SA(s): a peculiar galaxy), extracted from the sample of ring‐shaped galaxies compiled in Faúndez‐Abans & de Oliveira‐Abans. The main goal of this work is to investigate the spectral classification using the three line‐ratio diagrams, called diagnostic diagrams, of Veilleux & Osterbrock. However, in order to separate the different types of galaxies [H ii galaxies, Seyfert 2 galaxies and low‐ionization nuclear emission‐line region galaxies (LINERs)] we have to used empirical boundaries between them. Based on the observed spectra, we suggest G18 is a ‘weak‐[O i] LINER’ or even a ‘transition object’ or LINER/H ii. In the case of G19, we see Hβ in absorption and no [O iii] lines, impeding the [O iii]/Hβ ratio to be estimated. However, other lines ratios have been evaluated for the discussion. We classify the nature of G19 as ambiguous, because of the difficulty in determining its ionizing source (narrow‐line active galactic nuclei or H ii galaxies) in different diagnostic diagrams. The errors in the fluxes were mostly caused by uncertainties in the placement of the continuum level. We have estimated nuclear redshift of z= 0.034 (G18) and z= 0.039 (G19), corresponding to a heliocentric velocity of 10 246 and 11 734 km s−1, respectively. Some other physical parameters have been derived whenever possible. All spectra were reduced and analysed in a homogeneous way with the standard iraf procedures.