TWO NEW VARIABLE HOT DQ STARS

被引：19

作者：

Barlow, B. N. ^{[1
]}

Dunlap, B. H. ^{[1
]}

Rosen, R. ^{[2
]}

Clemens, J. C. ^{[1
]}

机构：

[1] Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA

[2] Natl Radio Astron Observ, Green Bank, WV 24944 USA

来源：

ASTROPHYSICAL JOURNAL LETTERS | 2008年 / 688卷 / 02期

基金：

美国国家科学基金会;

关键词：

stars: oscillations; stars: variables: other; white dwarfs;

D O I：

10.1086/595584

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We have discovered periodic variations in the light curves of two hot DQ stars from the Sloan Digital Sky Survey, SDSS J220029.08-074121.5 and SDSS J234843.30-094245.3. These are the second and third variables detected among the hot DQs and confirm the existence of a new class of variable white dwarf stars. The amplitudes of the variations are one half as large as those detected in the first discovered variable, SDSS J142625.71 + 575218.3, and required high signal-to-noise photometry to detect. The pulse shapes of the stars are not like those of known white dwarf pulsators but are similar to the first hot DQ variable, SDSS J142625.71 + 575218.3.

引用

页码：L95 / L98

页数：4

共 14 条

[1]

BRICKHILL AJ, 1990, MON NOT R ASTRON SOC, V246, P510

[2] The Goodman Spectrograph [J].

Clemens, JC ;

Crain, JA ;

Anderson, R .

GROUND-BASED INSTRUMENTATION FOR ASTRONOMY, PTS 1-3, 2004, 5492 :331-340

[3] Hot DQ white dwarfs: Something different [J].

Dufour, P. ;

Fontaine, G. ;

Liebert, James ;

Schmidt, G. D. ;

Behara, N. .

ASTROPHYSICAL JOURNAL, 2008, 683 (02) :978-989

[4] Sdss J142625.71+575218.3: The first pulsating white dwarf with a large detectable magnetic field [J].

Dufour, P. ;

Fontaine, G. ;

Liebert, James ;

Williams, Kurtis ;

Lai, David K. .

ASTROPHYSICAL JOURNAL LETTERS, 2008, 683 (02) :L167-L170

[5]

Dufour P, 2008, ASTR SOC P, V391, P241

[6] White dwarf stars with carbon atmospheres [J].

Dufour, P. ;

Liebert, J. ;

Fontaine, G. ;

Behara, N. .

NATURE, 2007, 450 (7169) :522-524

[7] Might carbon-atmosphere white dwarfs harbour a new type of pulsating star? [J].

Fontaine, G. ;

Brassard, P. ;

Dufour, P. .

ASTRONOMY & ASTROPHYSICS, 2008, 483 (01) :L1-L4

[8] Gravity modes in ZZ Ceti stars. I. Quasi-adiabatic analysis of overstability [J].

Goldreich, P ;

Wu, YQ .

ASTROPHYSICAL JOURNAL, 1999, 511 (02) :904-915

[9] A PRESCRIPTION FOR PERIOD ANALYSIS OF UNEVENLY SAMPLED TIME-SERIES [J].

HORNE, JH ;

BALIUNAS, SL .

ASTROPHYSICAL JOURNAL, 1986, 302 (02) :757-763

[10]

Montgomery M., 1999, DELTA SCUTI STAR NEW, V13, P28

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