Publications (22)
The rings of (2060) Chiron: Evidence of an evolving system
C. L. Pereira, F. Braga-Ribas, B. Sicardy +54
The centaur (2060) Chiron has long been a candidate for hosting material in orbit, based on occultation and photometric and spectroscopic data. Here, we present a multichord stella…
Photometry and dynamics of the minor mergers AM\,1228-260 and AM\,2058-381
J. A. Hernandez-Jimenez, M. G. Pastoriza, C. Bonatto +3
We investigate interaction effects on the dynamics and morphology of the galaxy pairs AM\,2058-381 and AM\,1228-260. This work is based on images and long-slit spectra obtaine…
Kinematics of Black Hole X-ray Binary GRS 1915+105
V. Dhawan, I. F. Mirabel, M. Ribo +1
The space velocity of a stellar black hole encodes the history of its formation and evolution. Here we measure the 3-dimensional motion of the microquasar GRS 1915+105, using a dec…
Study of the Kelvin-Helmholtz instability through simulation with the code Athena
P. Freitas-Lemes, I. Rodrigues, M. Faúndez-Abans
Kelvin-Helmholtz instabilities are common in astrophysical systems, ranging from jet black holes up to protoplanetary accretion disk. An astrophysical object with strong characteri…
2D kinematic study of the central region of NGC 4501
P. Repetto, M. Faundez-Abans, P. Freitas-Lemes +2
GMOS-IFU observational data were used to study the detailed two dimensional gas kinematics and morphological structures within the ~500x421 pc^2 of the active Seyfert 2 galaxy NGC…
The runaway black hole GRO J1655-40
I. F. Mirabel, R. Mignani, I. Rodrigues +3
We have used the Hubble Space Telescope to measure the motion in the sky and compute the galactocentric orbit of the black hole X-ray binary GRO J1655-40. The system moves with a r…
Imagery and long-slit spectroscopy of the Polar-Ring Galaxy AM2020-504
P. Freitas-Lemes, I. Rodrigues, M. Faúndez-Abans +2
Interactions between galaxies are very common. There are special kinds of interactions that produce systems called Polar Ring Galaxies (PRGs), composed by a lenticular, elliptical,…
On the central abundances of Active Galactic Nuclei and Star-forming Galaxies
O. L. Dors, M. V. Cardaci, G. F. Hagele +5
We examine the relation between oxygen abundances in the narrow-line regions (NLRs) of active galactic nuclei (AGNs) estimated from the optical emission lines through the strong-li…
Kinematics and physical properties of Southern interacting galaxies: the minor merger AM 2306-721
A. C. Krabbe, M. G. Pastoriza, Claudia Winge +2
We present an observational study about the effects of the interactions in the kinematics, stellar population and abundances of the components of the galaxy pair AM2306-721. Rotati…
A microquasar shot out from its birth place
I. F. Mirabel, I. Rodrigues, Q. Z. Liu
We show that the microquasar LSI+61303 is running away from its birth place in a young complex of massive stars. The supernova explosion that formed the compact object shot out the…
The effects of the interaction on the kinematics, stellar population and metallicity of AM2322-821 with Gemini/GMOS
A. C. Krabbe, M. G. Pastoriza, C. Winge +3
We present an observational study about the impacts of the interactions in the kinematics, stellar populations, and oxygen abundances of the components of the galaxy pair AM\,2322-…
The Southern Photometric Local Universe Survey (S-PLUS): improved SEDs, morphologies and redshifts with 12 optical filters
C. Mendes de Oliveira, T. Ribeiro, W. Schoenell +142
The Southern Photometric Local Universe Survey (S-PLUS) is imaging ~9300 deg^2 of the celestial sphere in twelve optical bands using a dedicated 0.8 m robotic telescope, the T80-So…
Are the hosts of Gamma-Ray Bursts sub-luminous and blue galaxies?
E. Le Floc'h, P. -A. Duc, I. F. Mirabel +11
We present K-band imaging observations of ten Gamma-Ray Burst (GRB) host galaxies. We compare their observed and absolute K magnitudes as well as their R-K colours with those of ot…
Photometry and Dynamics of the Minor Merger AM1219-430 with Gemini GMOS-S
J. A. Hernandez-Jimenez, M. G. Pastoriza, I. Rodrigues +3
We present an observational study of the interaction effect on the dynamics and morphology of the minor merger AM1219-430. This work is based on r' and g' images and long-slit spec…
A study of the remarkable galaxy system AM 546-324 (the core of Abell S0546)
M. Faúndez-Abans, A. C. Krabbe, M. Oliveira-Abans +4
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 cl…
Analysis of nuclear activity of ten polar ring galaxies
P. Freitas-Lemes, I. Rodrigues, O. L. Dors +1
The accumulation of mass from the interaction process that forms the polar ring galaxies is a factor that favors the conditions necessary to trigger nonthermal nuclear activities..…
Assessing Disk Galaxy Stability through Time
D. Valencia-EnrÃquez, I. Puerari, I. Rodrigues
N-body simulations have shown that a bar in a galaxy can be triggered by two processes: (1) by its own instabilities in the disk, or (2) by interactions with other galaxies. Both m…
Interaction effects on galaxy pairs with Gemini/GMOS- II: Oxygen abundance gradients
D. A. Rosa, O. L. Dors, A. C. Krabbe +5
In this paper we derived oxygen abundance gradients from HII regions located in eleven galaxies in eight systems of close pairs. Long-slit spectra in the range 4400-7300A were obta…
Eight luminous early-type galaxies in nearby pairs and sparse groups I. Stellar populations spatially analysed
D. A. Rosa, A. C. Milone, A. C. Krabbe +1
We present a detailed spatial analysis of stellar populations based on long-slit optical spectra in a sample of eight luminous early-type galaxies selected from nearby sparse group…
A high-velocity black hole on a Galactic-halo orbit in the solar neighborhood
I. F. Mirabel, V. Dhawan, R. P. Mignani +2
Only a few of the dozen or so stellar-mass black holes have been observed away from the plane of the Galaxy. Those few could have been ejected from the plane as a result of a `…
Interaction effects on galaxy pairs with Gemini/GMOS- I: Electron density
A. C. Krabbe, D. A. Rosa, O. L. Dors +5
We present an observational study about the impacts of the interactions in the electron density of \ion{H}{ii} regions located in 7 systems of interacting galaxies. The data consis…
VLT and HST Observations of the Host Galaxy of GRB990705
E. Le Floc'h, P. -A. Duc, I. F. Mirabel +6
We present VLT spectroscopic observations of Gamma-Ray Burst (GRB) 990705 host galaxy and highlight the benefits provided by the prompt-phase features of GRBs to derive the redshif…