When nature tries to trick us. An eclipsing eccentric close binary superposed on the central star of the planetary nebula M 3-2

Boffin, H. M. J.; Jones, D.; Wesson, Roger; Beletsky, Yuri; Miszalski, Brent; Saviane, Ivo; Monaco, Lorenzo; Corradi, R.; Santander García, Miguel; Rodríguez-Gil, P.
Bibliographical reference

Astronomy and Astrophysics, Volume 619, id.A84, 8 pp.

Advertised on:
11
2018
Number of authors
10
IAC number of authors
3
Citations
12
Refereed citations
11
Description
Bipolar planetary nebulae (PNe) are thought to result from binary star interactions and, indeed, tens of binary central stars of PNe have been found, in particular using photometric time-series that allow for the detection of post-common envelope systems. Using photometry at the NTT in La Silla we have studied the bright object close to the centre of PN M 3-2 and found it to be an eclipsing binary with an orbital period of 1.88 days. However, the components of the binary appear to be two A or F stars, of almost equal mass, and are therefore too cold to be the source of ionisation of the nebula. Using deep images of the central star obtained in good seeing conditions, we confirm a previous result that the central star is more likely much fainter, located 2″ away from the bright star. The eclipsing binary is thus a chance alignment on top of the planetary nebula. We also studied the nebular abundance and confirm it to be a Type I PN. Based on ESO observations made under programmes 088.D-0573(A), 090.D-0435(A), 090.D-0693(A), 091.D-0475(A), 092.D-0449(A), 094.D-0031(A), 094.D-0031(A), and 096.D-0237(A).Tables A.1 and A.2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.125.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/619/A84
Related projects
Planetary Nebula "The Necklace"
Bipolar Nebulae
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
Antonio
Mampaso Recio
Representación de la variable cataclísmica SS Cygni (Chris Moran)
Binary Stars
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
Pablo
Rodríguez Gil