ausblenden:
Schlagwörter:
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Zusammenfassung:
Type Ia supernovae (SN Ia) are amongst
the most energetic events in the Universe.
They are used as standard
candles
to measure cosmological distances
and they produce a rich nucleosynthesis;
they are fundamental objects
to understand the chemical evolution
of galaxies. It is thought that SN Ia are
produced by processes occurring
in tight binaries including at least one
carbon–
oxygen white dwarf (WD). Such
binaries could emerge from the dynamical
evolution of high-multiplicity
stellar
systems such as the young spectroscopic
quadruple HD 74438, recently
detected in the Gaia–ESO Survey.
Follow-
up spectroscopic observations
in South Africa and New Zealand, as
well as the use of archival ESO spectra,
allow us to characterise its orbital and
astrophysical parameters. Modelling
the dynamical evolution of stellar quadruples shows that such systems can
produce WD mergers, possible progenitors
of SN Ia.
