Unveiling the Dual Nature of V1180 Cas: UXor-like Dips and EXor-like Bursts across a Decade

Authors:
Open Access
Publisher website
Google Scholar
Abstract
We present a detailed analysis of the long-term photometric and spectroscopic evolution of V1180 Cas over a decade, aiming to identify the dominant mechanisms behind its variability. We combine multiband light curves from 1999 to 2025 with over 30 epochs of optical to near-infrared (NIR) spectroscopy (0.5–2.5 μ m), analyzing variability patterns, color behavior, and emission line diagnostics. We investigate the temporal evolution of accretion and outflow indicators and their correlation with photometric states. The light curve reveals a transition from sporadic early dimming events to a quasi-periodic pattern since 2018, with 11 major dips showing asymmetry and stochastic substructure. Color–magnitude diagrams show classic UXor-like blueing during deep minima, while NIR and mid-infrared color changes indicate thermal evolution of the disk. Spectroscopic analysis reveals persistent hydrogen, Ca II , He I , and forbidden line emission. Accretion diagnostics track photometric variability, and forbidden lines often intensify during dips, implying a physical link between extinction and outflows. Estimated accretion rates range from ∼10 −8 to 10 −7 M ⊙ yr −1 ; the outflow rate and density diagnostics are consistent with disk winds and shock-excited jets. V1180 Cas demonstrates dual-mode variability driven by both variable circumstellar extinction and episodic accretion events. The hybrid UXor/EXor behavior, combined with evolving disk signatures and persistent outflows, suggests a young stellar object undergoing coupled accretion–extinction–outflow evolution. Continued monitoring will be essential to fully resolve the physical processes shaping its variability.
Funding Information
  • Department of Atomic Energy, Government of India (RTI 4002)
  • Thailand Science Research and Innovation (FFB680072/0269)
  • Department of Science and Technology, Ministry of Science and Technology, India (DST/INSPIRE 1375 Fellowship/2019/IF190550)
  • Department of Science and Technology, Ministry of Science and Technology, India (DST/INSPIRE 1411 Fellowship/2022/IF220587)
  • UNAM ∣ Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México (IN105225)

This publication has 83 references indexed in Scilit: