7 research outputs found
A grid of Synthetic Spectra for Hot DA White Dwarfs and Its Application in Stellar Population Synthesis
In this work we present a grid of LTE and non-LTE synthetic spectra of hot DA
white dwarfs (WDs). In addition to its usefulness for the determination of
fundamental stellar parameters of isolated WDs and in binaries, this grid will
be of interest for the construction of theoretical libraries for stellar
studies from integrated light. The spectral grid covers both a wide temperature
and gravity range, with 17,000 K <= T_eff <= 100,000 K and 7.0 <= log(g) <=
9.5. The stellar models are built for pure hydrogen and the spectra cover a
wavelength range from 900 A to 2.5 microns. Additionally, we derive synthetic
HST/ACS, HST/WFC3, Bessel UBVRI and SDSS magnitudes. The grid was also used to
model integrated spectral energy distributions of simple stellar populations
and our modeling suggests that DAs might be detectable in ultraviolet bands for
populations older than ~8 Gyr.Comment: to be published in The Astrophysical Journal Supplement Serie
GALExtin: an alternative online tool to determine the interstellar extinction in the Milky Way
International audienceEstimates of interstellar extinction are essential in a broad range of astronomical research. In the last decades, several maps and models of the large-scale interstellar extinction in the Galaxy have been published. However, these maps and models have been developed in different programming languages, with different user interfaces and input/output formats, which makes using and comparing results from these maps and models difficult. To address this issue, we have developed a tool called GALExtin (http://www.galextin.org), which estimates interstellar extinction based on both available 3D models/maps and 2D maps. The user only needs to provide a list with coordinates (and distance) and to choose a model/map. GALExtin will then provide an output list with extinction estimates. It can be implemented in any other portal or model that requires interstellar extinction estimates. Here, a general overview of GALExtin is presented, along with its capabilities, validation, performance and some results