Unresolved binary systems with white dwarfs in open star clusters

Cover Page

Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

We invesigate unresolved binary systems with components of main sequence star (MS) and white dwarf (WD) in nine open clusters. These systems are located below and to the left of the main sequence at the colour-magnitude diagram. We compare the number of cluster stars, which have likely evolved into white dwarfs, with the number of candidates for unresolved binary systems with WD. The number of probable cluster members, lying below the main sequence, is generally less than the expected number of white dwarfs. The observations in the ultraviolet could detect WDs and unresolved binary WD+MS systems more confidently than the observations in the visible range.

Full Text

Restricted Access

About the authors

V. O. Mikhnevich

Ural Federal University

Author for correspondence.
Email: varvara.mikhnevich@urfu.ru
Russian Federation, Еkaterinburg

A. F. Seleznev

Ural Federal University

Email: varvara.mikhnevich@urfu.ru
Russian Federation, Еkaterinburg

References

  1. M. Limongi, L. Roberti, A. Chieffi, and K. Nomoto, Astrophys. J. Suppl. 270, 29 (2024).
  2. I. Iben and M. Livio, Publ. Astron. Soc. Pacific 105, 1373 (1993).
  3. K. A. Postnov and L. R. Yungelson, Liv. Rev. Relativity 17, 3 (2014).
  4. M. Livio and N. Soker, Astrophys. J. 329, 764 (1988).
  5. T. M. Tauris, D. Sanyal, S.-C. Yoon, and N. Langer, Astron. and Astrophys. 558, id. A39 (2013).
  6. F. K. Röpke and O. de Marco, Liv. Rev. Computational Astrophys. 9(1), id. 2 (2023).
  7. J. D. Cummings, J. S. Kalirai, P.-E. Tremblay, E. Ramirez-Ruiz, and J. Choi, Astrophys. J. 866(1), id. 21 (2018).
  8. L. Ferrario, D. Wickramasinghe, J. Liebert, K. A. Williams, Monthly Not. Roy. Astron. Soc. 361(4), 1131 (2005).
  9. V.V. Nikiforova, M.V. Kulesh, A.F. Seleznev, and G. Carraro, Astron. J. 160(3), id. 142 (2020).
  10. J. Liebert, Ann. Rev. Astron. Astrophys. 18, 363 (1980).
  11. D. Koester and G. Chanmugam, Reports Progress Phys. 53, 837 (1990).
  12. L. G. Althaus, A. H. Córsico, J. Isern, and E. Garcia-Berro, Astron. and Astrophys. Rev. 18(4), 471 (2010).
  13. T. Prusti, J. H. J.de Bruijne, A. G. A. Brown, A. Vallenari, et al., Astron. and Astrophys. 595, id. A1 (2016).
  14. [ R. Ahumada, C. Allende Prieto, A. Almeida, F. Anders, et al., Astrophys. J. Suppl. 249(1), id. 3 (2020).
  15. N. P. Gentile Fusillo, P.-E. Tremblay, E. Cukanovaite, A. Vorontseva, et al., Monthly Not. Roy. Astron. Soc. 508(3), 3877 (2021).
  16. H. B. Richer, I. Caiazzo, H. Du, S. Grondin, et al., Astrophys. J. 912(2), id. 165 (2021).
  17. M. Prišegen, M. Piecka, N. Faltová, N., M. Kajan, and E. Paunzen, Astron. and Astrophys. 645, id. A13 (2021).
  18. M. Prišegen and N. Faltová, Astron. and Astrophys. 678, id. A20 (2023).
  19. H.A. Flewelling, E.A. Magnier, K.C. Chambers, J.N. Heasley, et al., Astrophys. J. Suppl. 251(1), id. 7 (2020).
  20. L. Bianchi, B. Shiao, and D. Thilker, Astrophys. J. Suppl. 230(2), id. 24 (2017).
  21. G. Duchéne and A. Kraus, Ann. Rev. Astron. Astrophys. 51(1), 269 (2013).
  22. A. E. Piskunov and O. Yu. Malkov, Astron. and Astrophys. 247, 87 (1991).
  23. R. de Grijs, S. P. Goodwin, M. B. N. Kouwenhoven, and P. Kroupa, Astron. and Astrophys. 492(3), 685 (2008).
  24. P. Kroupa, C. A. Tout, and G. Gilmore, Monthly Not. Roy. Astron. Soc. 251, 293 (1991).
  25. O.I. Borodina, A.F. Seleznev, G. Carraro, and V.M. Danilov, Astrophys. J. 874, id. 127 (2019).
  26. O.I. Borodina, G. Carraro, A.F. Seleznev, and V.M. Danilov, Astrophys. J. 908(1), id. 60 (2021).
  27. A. A. Malofeeva, A. F. Seleznev, and G. Carraro, Astron. J. 163(3), id. 113 (2022).
  28. A. A. Malofeeva, V. O. Mikhnevich, G. Carraro, G., and A. F. Seleznev, Astron. J. 165(2), id. 45 (2023).
  29. A. Bressan, P. Marigo, L. Girardi, B. Salasnich, C. Dal Cero, S. Rubele, and A. Nanni, Monthly Not. Roy. Astron. Soc. 427, 127 (2012).
  30. T. Cantat-Gaudin, F. Anders, A. Castro-Ginard, C. Jordi, et al., Astron. and Astrophys. 640, id. A1 (2020).
  31. W. S. Dias, H. Monteiro, A. Moitinho, J. R. D. Lepine, G. Carraro, E. Paunzen, B. Alessi, and L. Villela, Monthly Not. Roy. Astron. Soc. 504, 356 (2021).
  32. E. L. Hunt and S. Reffert, Astron. and Astrophys. 673, id. A114 (2023).
  33. P. Marigo, J. D. Cummings, J. L. Curtis, J. Kalirai, et al., Nature Astron. 4, 1102 (2020).
  34. P.D. Dobbie, R. Napiwotzki, M.R. Burleigh, K.A. Williams, R. Sharp, M. A. Barstow, S. L. Casewell, and I. Hubeny, Monthly Not. Roy. Astron. Soc. 395, 2248 (2009).
  35. J. Parada, H. Richer, J. Heyl, J. Kalirai, and R. Goldsbury, Astrophys. J. 826(1), id. 88 (2016).
  36. J. Parada, H. Richer, J. Heyl, J. Kalirai, and R. Goldsbury, Astrophys. J. 830(2), id. 139 (2016).
  37. P. A. Bergbusch and P. B. Stetson, Astron. J. 138, 1455 (2009).
  38. S. Chen, H. Richer, I. Caiazzo, and J. Heyl, Astrophys. J. 867(2), id. 132 (2018).
  39. Б. М. Шустов, М. Е. Сачков, А. А. Боярчук, Вестник ФГУП НПО им. С. А. Лавочкина 5, 4 (2014).
  40. А. Ф. Селезнев и В. О. Михневич, Научные труды Института астрономии РАН 8(5), 241 (2023).

Supplementary files

Supplementary Files
Action
1. JATS XML
Download
2. Fig. 1. PARSEC isochrones with solar metal abundances and age logarithms in years from 7.3 to 9.5. The position of the turning point is indicated by a black dot on each isochrone. The mass of the star in solar mass units corresponding to the turning point is indicated by an arrow. The age is indicated by a halftone gradient.

Download (81KB)
Indexing metadata
3. Fig. 2. CMD clusters of NGC 3532 in the Gaia photometric system. The solid black line shows the PARSEC isochrone [29], which best fits the cluster sequence. The dots show the cluster stars according to the data of [32]. The black stars indicate the selected MS stars. The open circles indicate the BCs associated with the cluster [18], and the squares indicate the simulated unresolved binary systems consisting of a BC and a MS star.

Download (61KB)
Indexing metadata
4. Fig. 3. CMD clusters of NGC 3532 in the Gaia photometric system. The solid black line shows the PARSEC isochrone, the dashed line shows the boundary of the region occupied by white dwarfs, according to [15]. The dots show the cluster stars according to [32]. The squares indicate the supposedly unresolved BC + GP systems — the cluster members lying below the main sequence. The open circles indicate the BC stellar magnitude estimates obtained for all possible mGP values ​​in the BC + GP system. The triangles are the cluster members falling within the BC region.

Download (79KB)
Indexing metadata
5. Fig. 4. On the left is the “stellar magnitude-color index” diagram of the NGC 3532 cluster sample in the Gaia photometric system [32]. On the right is the ratio of the abundance of objects evolved in the BD Nevol/Ntotal and the abundance of binary systems with a white dwarf NBD+GP/Ntotal; the gradient shows the age of the clusters under consideration.

Download (62KB)
Indexing metadata
6. Fig. 5. CMD clusters of NGC 3532 in the UV bands of the Hubble Space Telescope photometric system. The PARSEC isochrone is shown by the solid black line. The black stars indicate selected MS stars. The open circles indicate selected BCs from [35]. The squares indicate simulated unresolved binary systems consisting of a BC and a MS star.

Download (57KB)
Indexing metadata

Copyright (c) 2024 The Russian Academy of Sciences