DOI QR코드

DOI QR Code

The Barium Star HD204075: Iron Abundance and the Absence of Evidence for Accretion

  • 투고 : 2019.05.20
  • 심사 : 2019.08.16
  • 발행 : 2019.09.15

초록

Spectroscopic observations of barium star ${\zeta}$ Capricornus (HD204075) obtained at the 8.2 m telescope of the European Southern Observatory, with a spectral resolving power R = 80,000 and signal to noise ratio greater than 300, were used to refine the atmospheric parameters. We found new values for effective temperature ($T_{eff}=5,300{\pm}50K$), surface gravity ($log\;g=1.82{\pm}0.15$), micro-turbulent velocity ($v_{micro}=2.52{\pm}0.10km/s$), and iron abundance ($log\;N(Fe)=7.32{\pm}0.06$). Previously published abundances of chemical elements in the atmosphere of HD204075 were analyzed and no correlations of these abundances with the second ionization potentials of these elements were found. This excludes the possible influence of accretion of hydrogen and helium atoms from the interstellar or circumstellar environment to the atmosphere of this star. The accretion of nuclear processed matter from the evolved binary companion was primary cause of the abundance anomalies. The young age of HD204075 allows an estimation of the time-scale for the creation of the abundance anomalies arising from accretion of interstellar hydrogen and helium as is the case of stars with low magnetic fields; which we estimate should exceed $10^8$ years.

키워드

참고문헌

  1. Antipova LI, Boyarchuk AA, Pakhomov YV, Panchuk VE, analysis of atmospheric abundances in classical barium stars, Astron. rep. 48, 597-610 (2004). https://doi.org/10.1134/1.1777277
  2. Asplund M, Grevesse N, Sauval AJ, Scott P, The chemical composition of the sun, Annu. Rev. Astron. Astrophys. 47, 481-522 (2009). https://doi.org/10.1146/annurev.astro.46.060407.145222
  3. Bagnulo S, Jehin E, Ledoux C, Cabanac R, Melo C, et al., ESO Paranal Science Operations Team, The UVES paranal observatory project: a library of high-resolution spectra of stars across the hertzsprung-russell diagram, The Messenger. 114, 10 (2003). https://www.eso.org/sci/publications/messenger/archive/no.114-dec03/messenger-no114-10-14.pdf
  4. Biemont E, Palmeri P, Quinet P, D.R.E.A.M. database on rare Earths at Mons University (2002) [Internet], viewed 2017 Apr 14, available from: http://hosting.umons.ac.be/html/agif/databases/dream.html
  5. Bohm-Vitense E, The puzzle of the metallic line stars, Publ. Astron. Soc. Pac. 118, 419-435 (2006). http://doi.org/10.1086/499385
  6. Cenarro AJ, Peletier RF, Sánchez-Blázquez P, Salam SO, Toloba E, et al., Medium-resolution isaac newton telescope library of empirical spectra - II. The stellar atmospheric parameters, Mon. Not. R. Astron. Soc. 374, 664-690 (2007). http://doi.org/10.1111/j.1365-2966.2006.11196.x
  7. de Castro DB, Pereira CB, Roig F, Jilinski E, Drake NA, et al., Chemical abundances and kinematics of barium stars, Mon. Not. R. Astron. Soc. 459, 4299-4324 (2016). http://doi.org/10.1093/mnras/stw815
  8. Fuhr JR, Wiese WL, A critical compilation of atomic transition probabilities for neutral and singly ionized iron, J. Phys. Chem. Ref. Data 35, 1669-1809 (2006). http://doi.org/10.1063/1.2218876
  9. Gopka V, Yushchenko A, Lambert D, Drake N, Rostopchin S, Heaviest s-process elements in the atmospheres of barium stars, in Proceedings of the International Symposium on Nuclear Astrophysics-Nuclei in the Cosmos - IX, Geneva, Switzerland, 25-30 Jun 2006. http://pos.sissa.it/archive/conferences/028/105/NIC-IX_105.pdf
  10. Gopka VF, Yushchenko AV, Mishenina TV, Kim C, Musaev FA, et al., Atmospheric chemical composition of the halo star HD 221170 from a synthetic-spectrum analysis, Astron. Rep. 48, 577-587 (2004). http://doi.org/10.1134/1.1777275
  11. Greenstein JL, Analysis of the metallic-line stars. II. Astrophys. J. 109, 121-138 (1949). http://doi.org/10.1086/145112
  12. Havnes O, Abundances and acceleration mechanisms of cosmic rays, Nature, 229, 548-549 (1970). http://doi.org/10.1038/229548a0
  13. Havnes O, Magnetic stars as generators of cosmic rays, Astron. Astrophys. 13, 52-57 (1971). http://adsabs.harvard.edu/abs/1971A%26A....13...52H
  14. Havnes O, Conti PS, Magnetic accretion processes in peculiar a stars, Astron. Astrophys. 14, 1-11 (1971). http://adsabs.harvard.edu/abs/1971A%26A....14....1H
  15. Hirata R, Horaguchi T, VizieR online data catalog: Atomic spectral line list, SIMBAD Catalog VI/69 (1995). http://vizier.cfa.harvard.edu/viz-bin/Cat?VI/69
  16. Jeong Y, Yushchenko AV, Doikov DN, The interaction between accretion from the interstellar medium and accretion from the evolved binary component in barium stars, J. Astron. Space Sci. 35, 1-6 (2018). http://doi.org/10.5140/JASS.2017.35.1.1
  17. Kang YW, Yushchenko A, Hong K, Kim S, Yushchenko V, Chemical composition of the components of eclipsing binary star ZZ bootis, Astron. J. 144, A35 (2012). http://doi.org/10.1088/0004-6256/144/2/35
  18. Kang YW, Yushchenko AV, Hong K, Guinan EF, Gopka VF, Signs of accretion in the abundance patterns of the components of the RS CVn-type eclipsing binary star LX persei, Astron. J. 145, A167 (2013). http://doi.org/10.1088/0004-6256/145/6/167
  19. Kurucz RL, SYNTHE spectrum synthesis programs and line data (Kurucz CD-ROM, Smithsonian Astrophysical Observatory, Cambridge, MA, 1993)
  20. Luck RE, Parameters and abundances in luminous stars, Astron. J. 147, 137 (2014). http://doi.org/10.1088/0004-6256/147/6/137
  21. McWilliam A, High-resolution spectroscopic survey of 671 GK giants. I-Stellar atmosphere parameters and abundances, Astrophys. J. Sppl. 74, 1075-1128 (1990). http://doi.org/10.1086/191527
  22. Michaud G, Diffusion processes in peculiar a stars, Astrophys. J. 160, 641-658 (1970). http://doi.org/10.1086/150459
  23. Morton DC, Atomic data for resonance absorption lines. II. Wavelengths longward of the lyman limit for heavy elements, Astrophys. J. Suppl. Ser. 130, 403-436 (2000). http://doi.org/10.1086/317349
  24. Piskunov NE, Kupka F, Ryabchikova TA, Weiss WW, Jeffery CS, VALD: The vienna atomic line data base, Astron. Astrophys. Suppl. 112, 525-535 (1995). http://adsabs.harvard.edu/abs/1995A%26AS..112..525P
  25. Proffitt CR, Michaud G. Abundance anomalies in A and B stars and the accretion of nuclear-processed material from supernovae and evolved giants, Astrophys. J. 345, 998-1007 (1989). http://doi.org/10.1086/167969
  26. Prugniel Ph, Vauglin I, Koleva M, The atmospheric parameters and spectral interpolator for the MILES stars, Astron. Astrophys. 531, A165 (2011). http://doi.org/10.1051/0004-6361/201116769
  27. Scott P, Asplund M, Grevesse N, Bergemann M, Sauval AJ, The elemental composition of the Sun. II. The iron group elements Sc to Ni, Astron. Astrophys. 573, 33(2015). http://doi.org/10.1051/0004-6361/201424110
  28. Smiljanic R, Porto de Mello GF, da Silva L, Abundance analysis of barium and mild barium stars, Astron. Astrophys. 468, 679-693 (2007). http://doi.org/10.1051/0004-6361:20065867
  29. Sneden C, Lambert DL, Pilachowski CA, A study of CNO elements in barium stars, Astrophys. J. 247, 1052-1062 (1981). http://doi.org/10.1086/159114
  30. Yushchenko AV, URAN: A Software System for the Analysis of Stellar Spectra, in Proceedings of the 20th Stellar Conference of the Czech and Slovak Astronomical Institutes, Brno, Czech Republic, 5-7 Nov 1997.http://adsabs.harvard.edu/abs/1998vsr..conf..201Y
  31. Yushchenko AV, Gopka VF, Kang YW, Kim C, Lee BC, et al., The chemical composition of $\rho$ puppis and the signs of accretion in the atmospheres of B-F-type stars, Astron. J. 149, A59 (2015). http://doi.org/10.1088/0004-6256/149/2/59
  32. Yushchenko AV, Gopka VF, Khokhlova VL, Musaev FA, Bikmaev IF, Atmospheric chemical composition of the "twin" components of equal mass in the CP SB2 system 66 Eri, Astron. Lett. 25, 453-466 (1999). http://adsabs.harvard.edu/abs/1999AstL...25..453Y