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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

A new study of the spectroscopic binary 7 Vul with a Be star primary

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Author(s):
Harmanec, P. [1] ; Liptak, J. [1] ; Koubsky, P. [2] ; Bozic, H. [3] ; Labadie-Bartz, J. [4] ; Slechta, M. [2] ; Yang, S. [5] ; Harmanec, A. [6]
Total Authors: 8
Affiliation:
[1] Charles Univ Prague, Astron Inst, Fac Math & Phys, Holesovickach 2, Prague 18000 8 - Czech Republic
[2] Acad Sci, Astron Inst, Fricova 298, Ondrejov 25165 - Czech Republic
[3] Zagreb Univ, Fac Geodesy, Hvar Observ, Kaciceva 26, Zagreb 10000 - Croatia
[4] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Rua Matao 1226, Cidade Univ, BR-05508900 Sao Paulo, SP - Brazil
[5] Univ Victoria, Phys & Astron Dept, POB 3055 STN CSC, Victoria, BC V8W 3P6 - Canada
[6] Charles Univ Prague, Fac Math & Phys, Holesovickach 2, Prague 18000 8 - Czech Republic
Total Affiliations: 6
Document type: Journal article
Source: Astronomy & Astrophysics; v. 639, JUL 3 2020.
Web of Science Citations: 0
Abstract

We confirmed the binary nature of the Be star 7 Vul, derived a more accurate spectroscopic orbit with an orbital period of 69(.)(d)4212 +/- 0(.)(d)0034 69 . d 4212 +/- 0 . d 0034 , and improved the knowledge of the basic physical elements of the system. Analyzing available photometry and the strength of the H alpha emission, we also document the long-term spectral variations of the Be primary. In addition, we confirmed rapid light changes with a period of 0(.)(d)5592 0 . d 5592 , which is comparable to the expected rotational period of the Be primary, but note that its amplitude and possibly its period vary with time. We were able to disentangle only the HeI 6678 angstrom line of the secondary, which could support our tentative conclusion that the secondary appears to be a hot subdwarf. A search for this object in high-dispersion far-UV spectra could provide confirmation. Probable masses of the binary components are (6 +/- 1) ?(N)(circle dot) M circle dot N and (0.6 +/- 0.1) ?(N)(circle dot) M circle dot N . If the presence of a hot subdwarf is firmly confirmed, 7 Vul might be identified as a rare object with a B4-B5 primary; all Be + hot subdwarf systems found so far contain B0-B3 primaries. (AU)

FAPESP's process: 17/23731-1 - Analysis and Modeling of a Large Sample of Galactic Be Stars
Grantee:Jonathan Michael Labadie-Bartz
Support type: Scholarships in Brazil - Post-Doctorate