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arXiv · 2209.14629

DeGaPe 35: Amateur discovery of a new southern symbiotic star

Thomas Petit·Jaroslav Merc·Rudolf Gális·Stéphane Charbonnel·Thierry Demange·Richard Galli·Olivier Garde·Pascal Le Dû·Lionel Mulato
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Abstract

In this work, we present the discovery and characterization of a new southern S-type symbiotic star, DeGaPe 35. We have obtained the low-resolution spectroscopic observations and supplemented them with photometry from Gaia DR3 and other surveys. The optical spectra of this target show prominent emission lines, including highly ionized [Fe VII] and O VI lines. The cool component of this symbiotic binary is an M4-5 giant with effective temperature ~ 3 380 - 3 470 K and luminosity ~ 3 000 L$_\odot$ (for the adopted distance of 3 kpc). The hot component is a shell-burning white dwarf. The photometric observations of the Gaia satellite, published recently in the Gaia DR3 suggested the variability with the period of about 700 - 800 days that we tentatively attributed to the orbital motion of the binary.

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Thomas Petit, Jaroslav Merc, Rudolf Gális, Stéphane Charbonnel, Thierry Demange, Richard Galli, Olivier Garde, Pascal Le Dû, Lionel Mulato. 2022-09-29. DeGaPe 35: Amateur discovery of a new southern symbiotic star. https://doi.org/10.1016/j.newast.2022.101943

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