PIRSA:20090009

Stars stripped in binaries: from cosmic reionization to gravitational waves

Götberg, Y. (2020). Stars stripped in binaries: from cosmic reionization to gravitational waves. Perimeter Institute. https://pirsa.org/20090009

Götberg, Ylva. Stars stripped in binaries: from cosmic reionization to gravitational waves. Perimeter Institute, Sep. 10, 2020, https://pirsa.org/20090009 

          @misc{ pirsa_PIRSA:20090009,
            doi = {10.48660/20090009},
            url = {https://pirsa.org/20090009},
            author = {G{\"o}tberg, Ylva},
            keywords = {Strong Gravity},
            language = {en},
            title = {Stars stripped in binaries: from cosmic reionization to gravitational waves},
            publisher = {Perimeter Institute},
            year = {2020},
            month = {sep},
            note = {PIRSA:20090009 see, \url{https://pirsa.org}}
          }

Ylva Götberg

Carnegie Observatories

Talk number
PIRSA:20090009
Collection
Talk Type
Subject
Abstract

Most massive stars spend their lives in so close orbit with a companion star that severe mass exchange or even coalescence is inevitable as the stars evolve and swell. A third of massive stars are thus stripped of their fluffy, hydrogen-rich envelopes, leaving the compact helium core exposed. These stripped stars are so hot that most of their radiation is emitted in the ionizing regime. Using evolutionary and spectral models of stripped stars, I will show how they sometimes dominate the ionizing emission from full stellar populations and even significantly contribute to cosmic reionization. With their hard ionizing spectra, stripped stars possibly leave observable traces, for example in the nebular spectrum of distant galaxies. 

Apart from being ionizing sources, stripped stars are also interesting to consider as gravitational wave emitters. Creating a population model, we predict that several stripped stars orbiting compact objects will be detectable by LISA.