Bibcode
Vazdekis, A.; Koleva, M.; Ricciardelli, E.; Röck, B.; Falcón-Barroso, J.
Referencia bibliográfica
Monthly Notices of the Royal Astronomical Society, Volume 463, Issue 4, p.3409-3436
Fecha de publicación:
12
2016
Número de citas
336
Número de citas referidas
305
Descripción
We present UV-extended E-MILES stellar population synthesis models
covering the spectral range λλ 1680-50 000 Å at
moderately high resolution. We employ the NGSL space-based stellar
library to compute spectra of single-age, single-metallicity stellar
populations in the wavelength range from 1680 to 3540 Å. These
models represent a significant improvement in resolution and
age/metallicity coverage over previous studies based on earlier
space-based libraries. These model spectra were joined with those we
computed in the visible using MILES, and other empirical libraries for
redder wavelengths. The models span the metallicity range -1.79≤
{[M/{H}]}≤ +0.26 and ages above 30 Myr, for a suite of initial mass
function types with varying slopes. We focus on the behaviour of
colours, spectra and line-strength indices in the UV range as a function
of relevant stellar population parameters. Whereas some indices
strengthen with increasing age and metallicity, as most metallicity
indicators in the visible, other indices peak around 3 Gyr for
metal-rich stellar populations, such as Mg at 2800 Å. Our models
provide reasonably good fits to the integrated colours and most line
strengths of the stellar clusters of the Milky Way and Large Magellanic
Cloud. Our full spectrum fits in the UV range for a representative set
of early-type galaxies (ETGs) of varying mass yield age and metallicity
estimates in very good agreement with those obtained in the optical
range. The comparison of UV colours and line strengths of massive ETGs
with our models reveals the presence of young stellar components, with
ages in the range 0.1-0.5 Gyr and mass fractions 0.1-0.5 per cent, on
the top of an old stellar population.