A photometric and spectroscopic study of NSVS 14256825: the second sdOB+dM eclipsing binary

被引:40
作者
Almeida, L. A. [1 ]
Jablonski, F. [1 ]
Tello, J. [1 ]
Rodrigues, C. V. [1 ]
机构
[1] Inst Nacl Pesquisas Espaciais MCTI, BR-12227010 Sao Jose Dos Campos, SP, Brazil
基金
巴西圣保罗研究基金会;
关键词
binaries: eclipsing; stars: fundamental parameters; stars: individual: NSVS 14256825; stars: low-mass; subdwarfs; LIMB-DARKENING COEFFICIENTS; HW VIR-TYPE; SPECTRAL-ANALYSIS; PG; 1336-018; SDB BINARY; AA DORADUS; LB; 3459; STARS; SYSTEM; PARAMETERS;
D O I
10.1111/j.1365-2966.2012.20891.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present an analysis of UBVRCICJH photometry and phase-resolved optical spectroscopy of NSVS 14256825, an HW Vir type binary. The members of this class consist of a hot subdwarf and a main-sequence low-mass star in a close orbit (Porb similar to 0.1 d). Using the primary-eclipse timings, we refine the ephemeris for the system, which has an orbital period of 0.110 37 d. From the spectroscopic data analysis, we derive the effective temperature, T1= 40 000 +/- 500 K, the surface gravity, log g1= 5.50 +/- 0.05, and the helium abundance, , for the hot component. Simultaneously modelling the photometric and spectroscopic data using the WilsonDevinney code, we obtain the geometrical and physical parameters of NSVS 14256825. Using the fitted orbital inclination and mass ratio (i= 82 degrees.5 +/- 0 degrees.3 and q=M2/M1= 0.260 +/- 0.012, respectively), the components of the system have M1= 0.419 +/- 0.070 M-circle dot, R1= 0.188 +/- 0.010 R-circle dot, M2= 0.109 +/- 0.023 M-circle dot and R2= 0.162 +/- 0.008 R-circle dot. From its spectral characteristics, the hot star is classified as a subdwarf OB (sdOB) star.
引用
收藏
页码:478 / 485
页数:8
相关论文
共 36 条
[1]  
[Anonymous], 1995, Markov Chain Monte Carlo in Practice
[2]   GENETIC ALGORITHMS IN ASTRONOMY AND ASTROPHYSICS [J].
CHARBONNEAU, P .
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 1995, 101 (02) :309-334
[3]   Testing the forward modeling approach in asteroseismology - II. Structure and internal dynamics of the hot B subdwarf component In the close eclipsing binary system PG 1336-018 [J].
Charpinet, S. ;
Van Grootel, V. ;
Reese, D. ;
Fontaine, G. ;
Green, E. M. ;
Brassard, P. ;
Chayer, P. .
ASTRONOMY & ASTROPHYSICS, 2008, 489 (01) :377-394
[4]  
Claret A, 1995, ASTRON ASTROPHYS SUP, V114, P247
[5]  
DIAZCORDOVES J, 1995, ASTRON ASTROPHYS SUP, V110, P329
[6]   ULTRAVIOLET-RADIATION FROM EVOLVED STELLAR POPULATIONS .1. MODELS [J].
DORMAN, B ;
ROOD, RT ;
OCONNELL, RW .
ASTROPHYSICAL JOURNAL, 1993, 419 (02) :596-614
[7]   HS 0705+6700: A new eclipsing sdB binary [J].
Drechsel, H ;
Heber, U ;
Napiwotzki, R ;
Ostensen, R ;
Solheim, JE ;
Johannessen, F ;
Schuh, SL ;
Deetjen, J ;
Zola, S .
ASTRONOMY & ASTROPHYSICS, 2001, 379 (03) :893-904
[8]  
Driebe T, 1998, ASTRON ASTROPHYS, V339, P123
[9]   Spectral analysis of sdB stars from the Hamburg Quasar Survey [J].
Edelmann, H ;
Heber, U ;
Hagen, HJ ;
Lemke, M ;
Dreizler, S ;
Napiwotzki, R ;
Engels, D .
ASTRONOMY & ASTROPHYSICS, 2003, 400 (03) :939-950
[10]   MODELING THE SYSTEM PARAMETERS OF 2M 1533+3759: A NEW LONGER PERIOD LOW-MASS ECLIPSING sdB plus dM BINARY [J].
For, B. -Q. ;
Green, E. M. ;
Fontaine, G. ;
Drechsel, H. ;
Shaw, J. S. ;
Dittmann, J. A. ;
Fay, A. G. ;
Francoeur, M. ;
Laird, J. ;
Moriyama, E. ;
Morris, M. ;
Rodriguez-Lopez, C. ;
Sierchio, J. M. ;
Story, S. M. ;
Strom, A. ;
Wang, C. ;
Adams, S. M. ;
Bolin, D. E. ;
Eskew, M. ;
Chayer, P. .
ASTROPHYSICAL JOURNAL, 2010, 708 (01) :253-267