ELEMENTAL COMPOSITIONS OF TWO EXTRASOLAR ROCKY PLANETESIMALS

被引：116

作者：

Xu, S. ^{[1
]}

Jura, M. ^{[1
]}

Koester, D. ^{[2
]}

Klein, B. ^{[1
]}

Zuckerman, B. ^{[1
]}

机构：

[1] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA

[2] Univ Kiel, Inst Theoret Phys & Astrophys, D-24098 Kiel, Germany

来源：

ASTROPHYSICAL JOURNAL | 2014年 / 783卷 / 02期

基金：

美国国家科学基金会;

关键词：

planetary systems; stars: abundances; white dwarfs; LOCAL INTERSTELLAR-MEDIUM; DBZ WHITE-DWARF; PLANETARY SYSTEMS; ECHELLE SPECTROGRAPH; CHEMICAL-COMPOSITION; SPECTROSCOPIC SURVEY; DEBRIS DISKS; ACCRETION; RICH; WATER;

D O I：

10.1088/0004-637X/783/2/79

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report Keck/HIRES and Hubble Space Telescope/COS spectroscopic studies of extrasolar rocky planetesimals accreted onto two hydrogen atmosphere white dwarfs, G29-38 and GD 133. In G29-38, eight elements are detected, including C, O, Mg, Si, Ca, Ti, Cr, and Fe while in GD 133, O, Si, Ca, and marginally Mg are seen. These two extrasolar planetesimals show a pattern of refractory enhancement and volatile depletion. For G29-38, the observed composition can be best interpreted as a blend of a chondritic object with some refractory-rich material, a result from post-nebular processing. Water is very depleted in the parent body accreted onto G29-38, based on the derived oxygen abundance. The inferred total mass accretion rate in GD 133 is the lowest of all known dusty white dwarfs, possibly due to non-steady state accretion. We continue to find that a variety of extrasolar planetesimals all resemble to zeroth order the elemental composition of bulk Earth.

引用

页数：16

共 94 条

[1] The origin and evolution of chondrites recorded in the elemental and isotopic compositions of their macromolecular organic matter [J].

Alexander, C. M. O'D. ;

Fogel, M. ;

Yabuta, H. ;

Cody, G. D. .

GEOCHIMICA ET COSMOCHIMICA ACTA, 2007, 71 (17) :4380-4403

[2] Chemical composition of the Earth and the volatility control on planetary genetics [J].

Allègre, C ;

Manhès, G ;

Lewin, É .

EARTH AND PLANETARY SCIENCE LETTERS, 2001, 185 (1-2) :49-69

[3]

ANDERSON DL, 2007, NEW THEORY EARTH, P1

[4] Dynamical effects of stellar mass-loss on a Kuiper-like belt [J].

Bonsor, A. ;

Mustill, A. J. ;

Wyatt, M. C. .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2011, 414 (02) :930-939

[5] A SPITZER SPACE TELESCOPE STUDY OF THE DEBRIS DISKS AROUND FOUR SDSS WHITE DWARFS [J].

Brinkworth, C. S. ;

Gaensicke, B. T. ;

Girven, J. M. ;

Hoard, D. W. ;

Marsh, T. R. ;

Parsons, S. G. ;

Koester, D. .

ASTROPHYSICAL JOURNAL, 2012, 750 (01)

[6] Organic molecules and water in the planet formation region of young circumstellar disks [J].

Carr, John S. ;

Najita, Joan R. .

SCIENCE, 2008, 319 (5869) :1504-1506

[7] Asteroseismology of DAV white dwarf stars and G29-38 [J].

Chen, Yan-Hui ;

Li, Yan .

RESEARCH IN ASTRONOMY AND ASTROPHYSICS, 2013, 13 (12) :1438-1444

[8] Accretion from debris disks onto white dwarfs Fingering (thermohaline) instability and derived accretion rates [J].

Deal, M. ;

Deheuvels, S. ;

Vauclair, G. ;

Vauclair, S. ;

Wachlin, F. C. .

ASTRONOMY & ASTROPHYSICS, 2013, 557

[9] DETECTION OF WEAK CIRCUMSTELLAR GAS AROUND THE DAZ WHITE DWARF WD 1124-293: EVIDENCE FOR THE ACCRETION OF MULTIPLE ASTEROIDS [J].

Debes, J. H. ;

Kilic, M. ;

Faedi, F. ;

Shkolnik, E. L. ;

Lopez-Morales, M. ;

Weinberger, A. J. ;

Slesnick, C. ;

West, R. G. .

ASTROPHYSICAL JOURNAL, 2012, 754 (01)

[10] Are there unstable planetary systems around white dwarfs? [J].

Debes, JH ;

Sigurdsson, S .

ASTROPHYSICAL JOURNAL, 2002, 572 (01) :556-565

← 1 2 3 4 5 6 7 8 9 10 →