The star formation history of the Sextans dwarf spheroidal galaxy: a true fossil of the pre-reionization era

Bettinelli, M.; Hidalgo, S. L.; Cassisi, S.; Aparicio, A.; Piotto, G.
Referencia bibliográfica

Monthly Notices of the Royal Astronomical Society, Volume 476, Issue 1, p.71-79

Fecha de publicación:
We present the star formation history (SFH) of the Sextans dwarf spheroidal galaxy based on deep archive B, I photometry taken with Suprime-Cam at Subaru telescope focusing our analysis on the inner region of the galaxy, fully located within the core radius. Within the errors of our SFH, we have not detected any metallicity gradient along the considered radial distance interval. As a main result of this work, we can state that the Sextans dwarf spheroidal stopped forming stars less than ˜1.3 Gyr after big bang in correspondence to the end of the reionization epoch. We have been able to constrain the duration of the main burst of star formation to ˜0.6 Gyr. From the calculation of the mechanical luminosity released from supernovae (SNe) during the brief episode of star formation, there are strong indications that SNe could have played an important role in the fate of Sextans, by removing almost completely the gas component, so preventing a prolonged star formation.
Proyectos relacionados
Cúmulo Globular NGC 2808
Vía Láctea y galaxias cercanas

El objetivo general del Proyecto es el estudio de la estructura, historia evolutiva y proceso de formación de galaxias a través de sus poblaciones estelares resueltas, tanto a partir de fotometría como espectroscopia. El proyecto puede dividirse en cuatro líneas principales: I. Historia de formación estelar en el Grupo Local. El objetivo de esta

López Corredoira