Corradi, R. L. M.; Sabin, L.; Miszalski, B.; Rodríguez-Gil, P.; Santander-García, M.; Jones, D.; Drew, J. E.; Mampaso, A.; Barlow, M. J.; Rubio-Díez, M. M.; Casares, J.; Viironen, K.; Frew, D. J.; Giammanco, C.; Greimel, R.; Sale, S. E.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 410, Issue 2, pp. 1349-1359.
Description
IPHASX J194359.5+170901 is a new high-excitation planetary nebula with
remarkable characteristics. It consists of a knotty ring expanding at a
speed of 28 km s-1, and a fast collimated outflow in the form
of faint lobes and caps along the direction perpendicular to the ring.
The expansion speed of the polar caps is ˜100 km s-1,
and their kinematical age is twice as large as the age of the ring.
Time-resolved photometry of the central star of IPHASX J194359.5+170901
reveals a sinusoidal modulation with a period of 1.16 d. This is
interpreted as evidence for binarity of the central star, the brightness
variations being related to the orbital motion of an irradiated
companion. This is supported by the spectrum of the central star in the
visible range, which appears to be dominated by emission from the
irradiated zone, consisting of a warm (6000-7000 K) continuum, narrow C
III, C IV and N III emission lines, and broader lines from a flat H I
Balmer sequence in emission.
IPHASX J194359.5+170901 helps to clarify the role of (close) binaries in
the formation and shaping of planetary nebulae (PNe). The output of the
common-envelope (CE) evolution of the system is a strongly flattened
circumstellar mass deposition, a feature that seems to be distinctive of
this kind of binary system. Also, IPHASX J194359.5+170901 is among the
first post-CE PNe for which the existence of a high-velocity polar
outflow has been demonstrated. Its kinematical age might indicate that
the polar outflow is formed before the CE phase. This points to mass
transfer on to the secondary as the origin, but alternative explanations
are also considered.
Related projects
This project has three major objectives: 1) To determine the physico-chemical characteristics of bipolar planetary nebulae and symbiotic nebulae, to help understanding the origin of bipolarity and to test theoretical models, mainly models with binary central stars, aimed at explaining the observed morphology and kinematics. 2) To study the low
The study of binary stars is essential to stellar astrophysics. A large number of stars form and evolve within binary systems. Therefore, their study is fundamental to understand stellar and galactic evolution. Particularly relevant is that binary systems are still the best source of precise stellar mass and radius measurements. Research lines
