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

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2012年 / 423卷 / 01期

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

页码：478 / 485

页数：8

共 36 条

[11] BINARIES DISCOVERED BY THE MUCHFUSS PROJECT: SDSS J08205+0008-AN ECLIPSING SUBDWARF B BINARY WITH A BROWN DWARF COMPANION [J].

Geier, S. ;

Schaffenroth, V. ;

Drechsel, H. ;

Heber, U. ;

Kupfer, T. ;

Tillich, A. ;

Ostensen, R. H. ;

Smolders, K. ;

Degroote, P. ;

Maxted, P. F. L. ;

Barlow, B. N. ;

Gaensicke, B. T. ;

Marsh, T. R. ;

Napiwotzki, R. .

ASTROPHYSICAL JOURNAL LETTERS, 2011, 731 (02)

[12] SOUTHERN SPECTROPHOTOMETRIC STANDARDS .1. [J].

HAMUY, M ;

WALKER, AR ;

SUNTZEFF, NB ;

GIGOUX, P ;

HEATHCOTE, SR ;

PHILLIPS, MM .

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 1992, 104 (677) :533-552

[13] The origin of subdwarf B stars - II [J].

Han, Z ;

Podsiadlowski, P ;

Maxted, PFL ;

Marsh, TR .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2003, 341 (02) :669-691

[14] Discovery of a helium-core white dwarf progenitor [J].

Heber, U ;

Edelmann, H ;

Lisker, T ;

Napiwotzki, R .

ASTRONOMY & ASTROPHYSICS, 2003, 411 (03) :L477-L480

[15] Hot Subdwarf Stars [J].

Heber, Ulrich .

ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS, VOL 47, 2009, 47 :211-251

[16] New VIC photometry of the sdOB binary AA Dor and an improved photometric model [J].

Hilditch, RW ;

Kilkenny, D ;

Lynas-Gray, AE ;

Hill, G .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2003, 344 (02) :644-650

[17] On the reflection effect in three sdOB binary stars [J].

Hilditch, RW ;

Harries, TJ ;

Hill, G .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1996, 279 (04) :1380-1392

[18] The EC 14026 stars - VIII. PG 1336-018: a pulsating sdB star in an HW Vir-type eclipsing binary [J].

Kilkenny, D ;

O'Donoghue, D ;

Koen, C ;

Lynas-Gray, AE ;

van Wyk, F .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1998, 296 (02) :329-338

[19] On the sdOB primary of the post common-envelope binary AA Doradus (LB 3459) [J].

Klepp, S. ;

Rauch, T. .

ASTRONOMY & ASTROPHYSICS, 2011, 531

[20]

LUCY LB, 1967, Z ASTROPHYS, V65, P89

← 1 2 3 4 →