The physical properties and evolution of the interacting system AM1204-292

Author(s)

Rosa, D. A. ^[1] ; Rodrigues, I ^[1] ; Krabbe, A. C. ^[1] ; Milone, A. C. ^[2] ; Carvalho, S. ^[1]

Affiliation

^[1] Univ Vale Paraiba, Inst Pesquisa & Desenvolvimento IP&D, Av Shishima Hifumi 2911, BR-12244000 Sao Jose Dos Campos, SP - Brazil

^[2] Inst Nacl Pesquisas Espaciais INPE, Div Astrofis, Av Astronautas 1758, BR-12227010 Sao Jose Dos Campos, SP - Brazil

• Document type: Journal article
• Source: Monthly Notices of the Royal Astronomical Society; v. 501, n. 3, p. 3750-3766, MAR 2021.
• Web of Science Citations: 0

Abstract

We investigate interaction effects in the stellar and gas kinematics, stellar population, and ionized gas properties of the interacting galaxy pair AM1204-292,composed of NGC4105 and NGC4106. The data consist of long-slit spectra in the range 3000-7050 angstrom. The massive E3 galaxy NGC4105 presents a flat stellar velocity profile, while the ionized gas is in strong rotation, suggesting an external origin. Its companion, NGC4106, shows asymmetries in the radial velocity field, likely due to the interaction. The dynamics of the interacting pair were modelled using the P-Gadget3 treepm/sph code, from which we show that the system has just passed the first perigalacticum, which triggered an outbreak of star formation, currently at full maximum. We characterized the stellar population properties using the stellar population synthesis code starlight and, on average, both galaxies are predominantly composed of old stellar populations. NGC4105 has a slightly negative age gradient, comparable with that of the most massive elliptical galaxies, but a steeper metallicity gradient. The SB0 galaxy NGC4106 presents smaller radial variations in both age and metallicity in comparison with intermediate-mass early-type galaxies. These gradients have not been disturbed by interaction, since the star formation happened very recently and was not extensive in mass. Electron density estimates for the pair are systematically higher than those obtained in isolated galaxies. The central O/H abundances were obtained from photoionization models in combination with emission-line ratios, which resulted in 12 + log(O/H) = 9.03 +/- 0.02 and 12 + log(O/H) = 8.69 +/- 0.05 for NGC4105 and NGC4106, respectively. (AU)

• FAPESP's process: 13/17247-9 - Dynamics of isolated and interacting disk galaxies via N-body and SPH simulations
• Grantee: Irapuan Rodrigues de Oliveira Filho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/10489-0 - Study of the changes in the solar magnetic field based on radio observations
• Grantee: Caius Lucius Selhorst
• Support Opportunities: Regular Research Grants
• FAPESP's process: 16/21532-9 - An observational study of the physical and stellar properties of a sample of Hoag-type galaxies
• Grantee: Angela Cristina Krabbe
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/13250-0 - Minimum model of metallic nanoparticle surface and cluster for DNA nanosensors optimization
• Grantee: Priscila Pereira Fávero
• Support Opportunities: Regular Research Grants