Time-Evolution Images of the Hypergiant RW Cephei During the Re-brightening Phase Following the Great Dimming

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Anugu, Narsireddy, Gies, Douglas R., Roettenbacher, Rachael M., Monnier, John D., Montargés, Miguel, Mérand, Antoine, Baron, Fabien, Schaefer, Gail H., Shepard, Katherine A., Kraus, Stefan, Anderson, Matthew D., Codron, Isabelle, Gardner, Tyler, Gutierrez, Mayra, Köhler, Rainer, Kubiak, Karolina, Lanthermann, Cyprien, Majoinen, Olli, Scott, Nicholas J., Vollmann, Wolfgang
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866917755069923328
author Anugu, Narsireddy
Gies, Douglas R.
Roettenbacher, Rachael M.
Monnier, John D.
Montargés, Miguel
Mérand, Antoine
Baron, Fabien
Schaefer, Gail H.
Shepard, Katherine A.
Kraus, Stefan
Anderson, Matthew D.
Codron, Isabelle
Gardner, Tyler
Gutierrez, Mayra
Köhler, Rainer
Kubiak, Karolina
Lanthermann, Cyprien
Majoinen, Olli
Scott, Nicholas J.
Vollmann, Wolfgang
author_facet Anugu, Narsireddy
Gies, Douglas R.
Roettenbacher, Rachael M.
Monnier, John D.
Montargés, Miguel
Mérand, Antoine
Baron, Fabien
Schaefer, Gail H.
Shepard, Katherine A.
Kraus, Stefan
Anderson, Matthew D.
Codron, Isabelle
Gardner, Tyler
Gutierrez, Mayra
Köhler, Rainer
Kubiak, Karolina
Lanthermann, Cyprien
Majoinen, Olli
Scott, Nicholas J.
Vollmann, Wolfgang
contents Stars with initial masses larger than 8 solar masses undergo substantial mass loss through mechanisms that remain elusive. Unraveling the origins of this mass loss is important for comprehending the evolutionary path of these stars, the type of supernova explosion and whether they become neutron stars or black hole remnants. In 2022 December, RW Cep experienced the Great Dimming in its visible brightness, presenting a unique opportunity to understand mass loss mechanisms. Our previous observations of RW Cep from the CHARA Array, taken during the dimming phase, show a compelling asymmetry in the star images, with a darker zone on the west side of the star indicating presence of dust in front of the star in our line of sight. Here, we present multi-epoch observations from CHARA while the star re-brightened in 2023. We created images using three image reconstruction methods and an analytical model fit. Comparisons of images acquired during the dimming and re-brightening phases reveal remarkable differences. Specifically, the west side of RW Cep, initially obscured during the dimming phase, reappeared during the subsequent re-brightening phase and the measured angular diameter became larger by 8%. We also observed image changes from epoch to epoch while the star is brightening indicating the time evolution of dust in front of the star. We suggest that the dimming of RW Cep was a result from a recent surface mass ejection event, generating a dust cloud that partially obstructed the stellar photosphere.
format Preprint
id arxiv_https___arxiv_org_abs_2408_11906
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Time-Evolution Images of the Hypergiant RW Cephei During the Re-brightening Phase Following the Great Dimming
Anugu, Narsireddy
Gies, Douglas R.
Roettenbacher, Rachael M.
Monnier, John D.
Montargés, Miguel
Mérand, Antoine
Baron, Fabien
Schaefer, Gail H.
Shepard, Katherine A.
Kraus, Stefan
Anderson, Matthew D.
Codron, Isabelle
Gardner, Tyler
Gutierrez, Mayra
Köhler, Rainer
Kubiak, Karolina
Lanthermann, Cyprien
Majoinen, Olli
Scott, Nicholas J.
Vollmann, Wolfgang
Solar and Stellar Astrophysics
Stars with initial masses larger than 8 solar masses undergo substantial mass loss through mechanisms that remain elusive. Unraveling the origins of this mass loss is important for comprehending the evolutionary path of these stars, the type of supernova explosion and whether they become neutron stars or black hole remnants. In 2022 December, RW Cep experienced the Great Dimming in its visible brightness, presenting a unique opportunity to understand mass loss mechanisms. Our previous observations of RW Cep from the CHARA Array, taken during the dimming phase, show a compelling asymmetry in the star images, with a darker zone on the west side of the star indicating presence of dust in front of the star in our line of sight. Here, we present multi-epoch observations from CHARA while the star re-brightened in 2023. We created images using three image reconstruction methods and an analytical model fit. Comparisons of images acquired during the dimming and re-brightening phases reveal remarkable differences. Specifically, the west side of RW Cep, initially obscured during the dimming phase, reappeared during the subsequent re-brightening phase and the measured angular diameter became larger by 8%. We also observed image changes from epoch to epoch while the star is brightening indicating the time evolution of dust in front of the star. We suggest that the dimming of RW Cep was a result from a recent surface mass ejection event, generating a dust cloud that partially obstructed the stellar photosphere.
title Time-Evolution Images of the Hypergiant RW Cephei During the Re-brightening Phase Following the Great Dimming
topic Solar and Stellar Astrophysics
url https://arxiv.org/abs/2408.11906