TY - JOUR
T1 - SU Lyn - A transient symbiotic star
AU - Iłkiewicz, Krystian
AU - Mikołajewska, Joanna
AU - Scaringi, Simone
AU - Teyssier, François
AU - Stoyanov, Kiril A.
AU - Fratta, Matteo
N1 - Funding Information:
This work was supported by STFC [ST/T000244/1]. This research has been funded by the National Science Centre, Poland, through grant OPUS No. 2017/27/B/ST9/01940 and through grant K -06- H28/2 08.12.2018 ‘Binary stars with compact object’ (Bulgarian National Science Fund).
Publisher Copyright:
© 2022 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.
PY - 2022/2
Y1 - 2022/2
N2 - SU Lyn is a binary system composed of a white dwarf and a red giant star. Although it is known to be bright and variable at X-ray wavelengths, the optical counterpart of the source appeared as a single red giant without prominent emission lines. Because of the lack of optical features typical for interacting systems, the system was classified as a hidden symbiotic star. We present the results of optical monitoring of the system. While SU Lyn did not show substantial photometric variability, the spectroscopic observations revealed a complex behaviour. The system showed strong emission line variability, including P Cygni profiles, changing line emission environments, and variable reddening. Both X-ray and optical observations indicate that the components of SU Lyn were interacting only for a short time during the last twelve years of monitoring. For the first time, we showed that SU Lyn resembled a classical symbiotic star when it was X-ray bright, and remained hidden afterwards. We also discuss the current evolutionary status of the red giant, as well as possible future evolution of the system. We suggest that SU Lyn could be a progenitor of a classical, persistent symbiotic system.
AB - SU Lyn is a binary system composed of a white dwarf and a red giant star. Although it is known to be bright and variable at X-ray wavelengths, the optical counterpart of the source appeared as a single red giant without prominent emission lines. Because of the lack of optical features typical for interacting systems, the system was classified as a hidden symbiotic star. We present the results of optical monitoring of the system. While SU Lyn did not show substantial photometric variability, the spectroscopic observations revealed a complex behaviour. The system showed strong emission line variability, including P Cygni profiles, changing line emission environments, and variable reddening. Both X-ray and optical observations indicate that the components of SU Lyn were interacting only for a short time during the last twelve years of monitoring. For the first time, we showed that SU Lyn resembled a classical symbiotic star when it was X-ray bright, and remained hidden afterwards. We also discuss the current evolutionary status of the red giant, as well as possible future evolution of the system. We suggest that SU Lyn could be a progenitor of a classical, persistent symbiotic system.
KW - accretion, accretion discs
KW - binaries: symbiotic
KW - novae, cataclysmic variables
KW - stars: individual: SU Lyn
UR - http://www.scopus.com/inward/record.url?scp=85126448964&partnerID=8YFLogxK
U2 - 10.1093/mnras/stab3637
DO - 10.1093/mnras/stab3637
M3 - Article
AN - SCOPUS:85126448964
VL - 510
SP - 2707
EP - 2717
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 2
ER -