J/other/Nat/576.61 WDJ0914+1914 X-Shooter spectrum (Gansicke+, 2019)
Accretion of a giant planet onto a white dwarf star.
Gansicke B.T., Schreiber M.R., Toloza O., Gentile Fusillo N.P., Koester D.,
Manser C.J.
<Nature, 576, 61-64 (2019)>
=2019Natur.576...61G 2019Natur.576...61G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Stars, white dwarf ;
Spectra, optical
Abstract:
The detection of a dust disk around the white dwarf star G29-38 and
transits from debris orbiting the white dwarf WD 1145+017
confirmed that the photospheric trace metals found in many white
dwarfs arise from the accretion of tidally disrupted planetesimals.
The composition of these planetesimals is similar to that of rocky
bodies in the inner Solar System. Gravitational scattering of
planetesimals towards the white dwarf requires the presence of more
massive bodies, yet no planet has so far been detected at a white
dwarf. Here we report optical spectroscopy of a hot (about
27750 kelvin) white dwarf, WD J091405.30+191412.25, that is accreting
from a circumstellar gaseous disk composed of hydrogen, oxygen and
sulfur at a rate of about 3.3x109 grams per second. The composition
of this disk is unlike all other known planetary debris around white
dwarfs, but resembles predictions for the makeup of deeper
atmospheric layers of icy giant planets, with H2O and H2S being
major constituents. A giant planet orbiting a hot white dwarf with a
semi-major axis of around 15 solar radii will undergo substantial
evaporation with expected mass loss rates comparable to the accretion
rate that we observe onto the white dwarf. The orbit of the planet is
most probably the result of gravitational interactions, indicating the
presence of additional planets in the system. We infer an occurrence
rate of approximately 1 in 10000 for spectroscopically detectable
giant planets in close orbits around white dwarfs.
Description:
WD J0914+1914 was observed on 2019 January 12 and 13 using X-Shooter32
mounted on UT2 of the Very Large Telescope. X-Shooter is a three-armed
spectrograph covering the extreme blue (UVB, 330-560nm), visual (VIS,
560nm-1um) and near-infrared (NIR, 1-2.4um) simultaneously.
Objects:
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RA (2000) DE Designation(s)
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09 14 05.30 +19 14 12.2 WDJ0914+1914 = SDSS J091405.30+191412.2
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 31 35446 Reduced and averaged X-Shooter spectrum of
WDJ0914+1914
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 F12.6 0.1nm lambda Wavelength
14- 22 E9.3 10mW/m2/nm Flux Flux (in erg/cm2/s/Å)
24- 31 E8.3 10mW/m2/nm e_Flux rms uncertainty on Flux
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 11-Mar-2020