The SN Ia runaway LP 398-9: detection of circumstellar material and surface rotation

Chandra, Vedant; Hwang, Hsiang-Chih; Zakamska, Nadia L.; Blouin, Simon; Swan, Andrew; Marsh, Thomas R.; Shen, Ken J.; Gänsicke, Boris T.; Hermes, J. J.; Putterman, Odelia; Bauer, Evan B.; Petrosky, Evan; Dhillon, Vikram S.; Littlefair, Stuart P.; Ashley, Richard P.
Referencia bibliográfica

Monthly Notices of the Royal Astronomical Society

Fecha de publicación:
6
2022
Número de autores
15
Número de autores del IAC
1
Número de citas
8
Número de citas referidas
7
Descripción
A promising progenitor scenario for Type Ia supernovae (SNeIa) is the thermonuclear detonation of a white dwarf in a close binary system with another white dwarf. After the primary star explodes, the surviving donor can be spontaneously released as a hypervelocity runaway. One such runaway donor candidate is LP 398-9, whose orbital trajectory traces back ≍105 yr to a known supernova remnant. Here, we report the discovery of carbon-rich circumstellar material around LP 398-9, revealed by a strong infrared excess and analysed with follow-up spectroscopy. The circumstellar material is most plausibly composed of inflated layers from the star itself, mechanically and radioactively heated by the past companion's supernova. We also detect a 15.4 h periodic signal in the UV and optical light curves of LP 398-9, which we interpret as surface rotation. The rotation rate is consistent with theoretical predictions from this supernova mechanism, and the brightness variations could originate from surface inhomogeneity deposited by the supernova itself. Our observations strengthen the case for this double-degenerate SNIa progenitor channel, and motivate the search for more runaway SNIa donors.
Proyectos relacionados
Agujero negro en erupción
Agujeros negros, estrellas de neutrones, enanas blancas y su entorno local

Los agujeros negros y estrellas de neutrones en binarias de rayos-X son laboratorios únicos para explorar la física de estos objetos compactos. No solo permiten confirmar la existencia de agujeros negros de origen estelar a través de mediciones dinámicas de sus masas, sino que también permiten investigar el comportamiento de la materia y la

Montserrat
Armas Padilla