The time/redshift evolution of radial abundance gradients

• Grant number: 12/22236-3
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Start date: July 15, 2013
• End date: January 14, 2014
• Field of knowledge: Physical Sciences and Mathematics - Astronomy
• Principal Investigator: Roberto Dell'Aglio Dias da Costa
• Grantee: Roberto Dell'Aglio Dias da Costa
• Visiting researcher: Mercedes Mollá Lorente
• Visiting researcher institution: Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Spain
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 10/18835-3 - Planetary nebulae, stars and chemical evolution of stellar systems, AP.TEM

Abstract

The time evolution of the radial abundance gradients within spiral galaxies is very controversial. The gradient steepening or flattening with time are both predicted and also observed. There are only two methods to produce a radial gradient: an infall of gas variable with radius and/or a star formation rate dependent on radius. Taking into account the relationship between the production of elements and the star formation, the radial distribution of abundances in a disk could give information about the local differences in the evolutionary histories along the galactocentric radius of a galaxy. The aim of this project is to study the possible evolution of radial abundance gradients along the time or the redshift by computing a new grid of chemical evolution models for a set of theoretical isolated galaxies with different dynamical masses. With this new grid of models we will update the one from Mollá \& Díaz (2005). Modifications will be applied to have a more realistic infall of gas law to form the disk, and to the creation of molecular clouds and stars from them. With these changes we might compare the models results with the observational data. These data will come mostly of the set of planetary nebulae observed by the IAG/USP group, where new techniques to better determine age and distance of these objects are being used. Besides that, the group is compiling a complete catalogue with abundances for these objects in the Milky Way and in other local galaxies. Moreover, we will analyze the current data on high redshift abundances to compare with our grid results in the earlier times. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MOLLA, MERCEDES; DIAZ, NGELES I.; GIBSON, BRAD K.; CAVICHIA, OSCAR; LOPEZ-SANCHEZ, ANGEL-R.. The role of gas infall in the evolution of disc galaxies. Monthly Notices of the Royal Astronomical Society, v. 462, n. 2, p. 1329-1340, OCT 21 2016. (09/54006-4, 12/22236-3)

MOLLA, MERCEDES; CAVICHIA, OSCAR; GAVILAN, MARTA; GIBSON, BRAD K.. Galactic chemical evolution: stellar yields and the initial mass function. Monthly Notices of the Royal Astronomical Society, v. 451, n. 4, p. 3693-3708, AUG 21 2015. (09/54006-4, 12/01017-1, 10/18835-3, 12/22236-3)

MOLLA, MERCEDES; DIAZ, ANGELES I.; ASCASIBAR, YAGO; GIBSON, BRAD K.. Galaxy chemical evolution models: the role of molecular gas formation. Monthly Notices of the Royal Astronomical Society, v. 468, n. 1, p. 305-318, JUN 2017. (12/22236-3, 09/54006-4)