Infrared photometric study of symbiotic stars

No paper of this nature should begin without a definition of symbiotic stars. It was Paul Merrill who, borrowing on his botanical background, coined the termsymbioticto describe apparently single stellar systems which combine the TiO absorption of M giants (temperature regime ≲ 3500 K) with He II emission (temperature regime ≳ 100,000 K). He and Milton Humason had in 1932 first drawn attention to three such stars: AX Per, CI Cyg and RW Hya. At the conclusion of the Mount Wilson Ha emission survey nearly a dozen had been identified, and Z And had become their type star. The numbers slowly grew, as much because the definition widened to include lower-excitation specimens as because new examples of the original type were found. In 1970 Wackerling listed 30; this was the last compendium of symbiotic stars published.

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SPECTRAL AND PHOTOMETRIC STUDY OF TWO OBJECTS IRAS 22023+5249 AND IRAS 06053+1837

NEWS OF THE NATIONAL ACADEMY OF SCIENCES OF THE REPUBLIC OF KAZAKHSTAN ◽

10.32014/2020.2518-1726.36 ◽

2020 ◽

Vol 3 (331) ◽

pp. 52-58

Author(s):

L.N. Kondratyeva ◽

◽

E.K. Denissyuk ◽

I.V. Reva ◽

M.A. Krugov ◽

...

Keyword(s):

Photometric Study

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Pre–Main-Sequence Stars in the Young Galactic Cluster IC 4996: A CCD Photometric Study

The Astronomical Journal ◽

10.1086/300547 ◽

1998 ◽

Vol 116 (4) ◽

pp. 1801-1809 ◽

Cited By ~ 11

Author(s):

Antonio J. Delgado ◽

Emilio J. Alfaro ◽

André Moitinho ◽

José Franco

Keyword(s):

Main Sequence ◽

Photometric Study ◽

Main Sequence Stars ◽

Galactic Cluster

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Discovery of five new Galactic symbiotic stars in the VPHAS+ survey

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab195 ◽

2021 ◽

Vol 502 (2) ◽

pp. 2513-2517

Author(s):

Stavros Akras ◽

Denise R Gonçalves ◽

Alvaro Alvarez-Candal ◽

Claudio B Pereira

Keyword(s):

Spectroscopic Data ◽

Selection Criterion ◽

Optical Spectra ◽

Emission Lines ◽

High Rate ◽

Symbiotic Stars ◽

Selection Of

ABSTRACT We report the validation of a recently proposed infrared (IR) selection criterion for symbiotic stars (SySts). Spectroscopic data were obtained for seven candidates, selected from the SySt candidates of Akras et al. by employing the new supplementary IR selection criterion for SySts in the VST/OmegaCAM Photometric H-Alpha Survey. Five of them turned out to be genuine SySts after the detection of H α, He ii, and [O iii] emission lines as well as TiO molecular bands. The characteristic O vi Raman-scattered line is also detected in one of these SySts. According to their IR colours and optical spectra, all five newly discovered SySts are classified as S-type. The high rate of true SySts detections of this work demonstrates that the combination of the H α emission and the new IR criterion improves the selection of target lists for follow-up observations by minimizing the number of contaminants and optimizing the observing time.

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