J/ApJ/839/42 Spectrosc. of the circumstellar gas of WD1145+017 (Redfield+, 2017)
Spectroscopic evolution of disintegrating planetesimals: minute to month
variability in the circumstellar gas associated with WD 1145+017.
Redfield S., Farihi J., Cauley P.W., Parsons S.G., Gansicke B.T.,
Duvvuri G. M
<Astrophys. J., 839, 42 (2017)>
=2017ApJ...839...42R 2017ApJ...839...42R
ADC_Keywords: Stars, white dwarf ; Line Profiles ; Radial velocities ;
Equivalent widths
Keywords: circumstellar matter; line: profiles;
minor planets, asteroids: general; stars: abundances;
stars: individual (WD 1145+017); white dwarfs
Abstract:
With the recent discovery of transiting planetary material around
WD1145+017, a critical target has been identified that links the
evolution of planetary systems with debris disks and their accretion
onto the star. We present a series of observations, five epochs over a
year, taken with Keck and the VLT, which for the first time show
variability of circumstellar absorption in the gas disk surrounding
WD1145+017 on timescales of minutes to months. Circumstellar
absorption is measured in more than 250 lines of 14 ions among 10
different elements associated with planetary composition, e.g., O, Mg,
Ca, Ti, Cr, Mn, Fe, and Ni. Broad circumstellar gas absorption with a
velocity spread of 225km/s is detected, but over the course of a year
blueshifted absorption disappears, while redshifted absorption
systematically increases. A correlation of equivalent width and
oscillator strength indicates that the gas is not highly optically
thick (median τ∼2). We discuss simple models of an eccentric disk
coupled with magnetospheric accretion to explain the basic observed
characteristics of these high-resolution and high signal- to-noise
observations. Variability is detected on timescales of minutes in the
two most recent observations, showing a loss of redshifted absorption
for tens of minutes, coincident with major transit events and
consistent with gas hidden behind opaque transiting material. This
system currently presents a unique opportunity to learn how the gas
causing the spectroscopic, circumstellar absorption is associated with
the ongoing accretion evidenced by photospheric contamination, as well
as the transiting planetary material detected in photometric
observations.
Description:
Observations of WD 1145+017 were taken on 2015 November 14 using HIRES
on Keck I as part of program 15B/N116Hb (PI: Redfield). The
approximate resolving power of the observations is R∼34000; the
observed spectrum ranges from 3100-5890Å.
Observations of WD 1145+017 were also performed with X-shooter on the
VLT on 2016 February 14, March 29, and April 8, under Director's
Discretionary Time Program 296.C-5014 (PI: Farihi). All observations
were through slits of 0.8", 0.9", and 0.9" for UVB, VIS, and NIR,
respectively, resulting in nominal resolving powers of R∼6200, 7450,
and 5300.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
11 48 33.63 +01 28 59.4 WD 1145+017 = LBQS 1145+0145
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 408 256 Detected circumstellar absorption features and
fit parameters
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See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)
J/MNRAS/449/574 : Circumstellar discs at white dwarfs (Rocchetto+, 2015)
J/MNRAS/452/765 : White dwarf cand. using LAMOST DR3 (Gentile Fusillo+, 2015)
J/ApJ/818/L7 : High-speed photom. of WD 1145+017 syst. (Gansicke+, 2016)
J/ApJS/222/14 : Planetary cand. from 1st yr K2 mission (Vanderburg+, 2016)
J/ApJS/226/7 : Planet cand. from K2's 1st yr (Crossfield+, 2016)
J/A+A/603/A30 : Evidence for 2 distinct giant planet pop. (Santos+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ion Ion with detected circumstellar absorption
7- 14 F8.3 0.1nm lambda [3056.8/8662.2] Rest wavelength of ion (RWave)
16- 20 F5.2 eV Elow [0/10.5] Energy of lower level
22- 26 F5.2 eV Eup [0.4/10.8] Energy of upper level
28- 33 F6.3 --- loggf [-4/0.6] log gf of transition
35- 39 F5.3 --- DepthK1 [0.01/0.3]? Normalized depth of circumstellar
feature, 2015 Apr Keck data (DepthKeckApr15)
41- 45 F5.3 --- E_DepthK1 [0.002/0.04]? Plus Error on DepthK1
(E_DepthKeckApr15)
47- 51 F5.3 --- e_DepthK1 ? Minus Error on DepthK1 (eDepthKeckApr152)
53- 58 F6.1 km/s VminK1 [-395/133]? Minimum radial velocity of
circumstellar feature, 2015 Apr Keck data
(VminKApr15)
60- 64 F5.1 km/s E_VminK1 ? Plus Error on VminK1 (E_VminKApr15)
66- 70 F5.1 km/s e_VminK1 [1.4/145]? Minus Error on VminK1
(eVminKApr152)
72- 77 F6.1 km/s VmaxK1 [-109/521]? Maximum radial velocity of
circumstellar feature, 2015 Apr Keck data
(VmaxKeckApr15)
79- 83 F5.1 km/s E_VmaxK1 [1/140]? Plus Error on VmaxK1 (E_VmaxKeckApr15)
85- 89 F5.1 km/s e_VmaxK1 ? Minus Error on VmaxK1 (eVmaxKeckApr152)
91- 91 A1 --- l_EWK1 Limit flag on EWK1 (l_EWKeckApr15)
92- 96 F5.3 0.1nm EWK1 [0.01/3]? Equivalent width of circumstellar
feature, 2015 Apr Keck data (EWKeckApr15)
98-102 F5.3 0.1nm E_EWK1 ? Plus Error on EWK1 (E_EWKeckApr15)
104-108 F5.3 0.1nm e_EWK1 [0.004/0.3]? Minus Error on EWK1
(eEWKeckApr152)
110-114 F5.3 --- DepthK2 [0.02/3.1]? Normalized depth of circumstellar
feature, 2015 Nov Keck data (DepthKeckNov15)
116-120 F5.3 --- E_DepthK2 [0.005/0.8]? Plus Error on DepthK2
122-126 F5.3 --- e_DepthK2 ? Minus Error on DepthK2
128-133 F6.1 km/s VminK2 [-433/153]? Minimum radial velocity of
circumstellar feature, 2015 Nov Keck data
(VminKeckNov15)
135-139 F5.1 km/s E_VminK2 ? Plus Error on VminK2 (E_VminKeckNov15)
141-145 F5.1 km/s e_VminK2 [1/146]? Minus Error on VminK2
(eVminKeckNov152)
147-151 F5.1 km/s VmaxK2 [-93/528]? Maximum radial velocity of
circumstellar feature, 2015 Nov Keck data
(VmaxKeckNov15)
153-157 F5.1 km/s E_VmaxK2 ? Plus Error on VmaxK2 (E_VmaxKeckNov15)
159-163 F5.1 km/s e_VmaxK2 [0/128]? Minus Error on VmaxK2
(eVmaxKeckNov152)
165-165 A1 --- l_EWK2 Limit flag on EWK2 (l_EWKeckNov15)
166-170 F5.3 0.1nm EWK2 [0.01/2]? Equivalent width of circumstellar
feature, 2015 Nov Keck data (EWKeckNov15)
172-176 F5.3 0.1nm E_EWK2 ? Plus Error on EWK2 (E_EWKeckNov15)
178-182 F5.3 0.1nm e_EWK2 [0.007/0.2]? Minus Error on on EWK2
(eEWKeckNov152)
184-188 F5.3 --- DepthV1 [0.01/0.7]? Normalized depth of circumstellar
feature, 2016 Feb VLT data (DepthVLTFeb16)
190-194 F5.3 --- E_DepthV1 [0.002/0.7]? Plus Error on DepthV1
(E_DepthVLTFeb16)
196-200 F5.3 --- e_DepthV1 ? Minus Error on DepthV1 (eDepthVLTFeb162)
202-207 F6.1 km/s VminV1 [-963/620]? Minimum radial velocity of
circumstellar feature, 2016 Feb VLT data
(VminVLTFeb16)
209-213 F5.1 km/s E_VminV1 ? Plus Error on VminV1 (E_VminVLTFeb16)
215-219 F5.1 km/s e_VminV1 [0.9/523]? Minus Error on VminV1
(eVminVLTFeb162)
221-226 F6.1 km/s VmaxV1 [-299/885]? Maximum radial velocity of
circumstellar feature, 2016 Feb VLT data
(VmaxVLTFeb16)
228-232 F5.1 km/s E_VmaxV1 [0.5/174]? Plus Error on VmaxV1 (E_VmaxVLTFeb16)
234-238 F5.1 km/s e_VmaxV1 ? Minus Error on VmaxV1 (eVmaxVLTFeb162)
240-240 A1 --- l_EWV1 Limit flag on EWV1
241-245 F5.3 0.1nm EWV1 [0.02/2.3] Equivalent width of circumstellar
feature, 2016 Feb VLT data (EWVLTFeb16)
247-251 F5.3 0.1nm E_EWV1 [0.007/0.4]? Plus Error on EWV1 (E_EWVLTFeb16)
253-257 F5.3 0.1nm e_EWV1 ? Minus Error on EWV1 (eEWVLTFeb162)
259-263 F5.3 --- DepthV2 [0.009/3]? Normalized depth of circumstellar
feature, 2016 Mar VLT data (DepthVLTMar16)
265-269 F5.3 --- E_DepthV2 [0.002/1.4]? Plus Error on DepthV2
(E_DepthVLTMar16)
271-275 F5.3 --- e_DepthV2 ? Minus Error on DepthV2 (eDepthVLTMar162)
277-282 F6.1 km/s VminV2 [-988/269]? Minimum radial velocity of
circumstellar feature, 2016 Mar VLT data
(VminVLTMar16)
284-288 F5.1 km/s E_VminV2 ? Plus Error on VminV2 (E_VminVLTMar16)
290-294 F5.1 km/s e_VminV2 [1/237]? Minus Error on VminV2
(eVminVLTMar162)
296-301 F6.1 km/s VmaxV2 [-185/593]? Maximum radial velocity of
circumstellar feature, 2016 Mar VLT data
(VmaxVLTMar16)
303-307 F5.1 km/s E_VmaxV2 [0.4/113]? Plus Error on VmaxV2 (E_VmaxVLTMar16)
309-313 F5.1 km/s e_VmaxV2 ? Minus Error on VmaxV2 (eVmaxVLTMar162)
315-315 A1 --- l_EWV2 Limit flag on EWV2
316-320 F5.3 0.1nm EWV2 [0.01/3.4] Equivalent width of circumstellar
feature, 2016 Mar VLT data (EWVLTMar16)
322-326 F5.3 0.1nm E_EWV2 [0.006/0.4]? Plus Error on EWV2 (E_EWVLTMar16)
328-332 F5.3 0.1nm e_EWV2 ? Minus Error on EWV2 (eEWVLTMar162)
334-338 F5.3 --- DepthV3 [0.01/0.5]? Normalized depth of circumstellar
feature, 2016 Apr VLT data (DepthVLTApr16)
340-344 F5.3 --- E_DepthV3 [0.001/0.2]? Plus Error on DepthV3
346-350 F5.3 --- e_DepthV3 ? Minus Error on DepthV3
352-357 F6.1 km/s VminV3 [-974/240]? Minimum radial velocity of
circumstellar feature, 2016 Apr VLT data
(VminVLTApr16)
359-363 F5.1 km/s E_VminV3 ? Plus Error on VminV3 (E_VminVLTApr16)
365-369 F5.1 km/s e_VminV3 [0.2/127]? Minus Error on VminV3
(eVminVLTApr162)
371-375 F5.1 km/s VmaxV3 [-73/580]? Maximum radial velocity of
circumstellar feature, 2016 Apr VLT data
(VmaxVLTApr16)
377-381 F5.1 km/s E_VmaxV3 [0.2/85]? Plus Error on VmaxV3 (E_VmaxVLTApr16)
383-387 F5.1 km/s e_VmaxV3 ? Minus Error on VmaxV3 (eVmaxVLTApr162)
389-389 A1 --- l_EWV3 Limit flag on EWV3 (l_EWVLTApr16)
390-394 F5.3 0.1nm EWV3 [0.02/3.3] Equivalent width of circumstellar
feature, 2016 Apr VLT data (EWVLTApr16)
396-400 F5.3 0.1nm E_EWV3 [0.004/0.2]? Plus Error on EWV3 (E_EWVLTApr16)
402-406 F5.3 0.1nm e_EWV3 ? Minus Error on EWV3 (eEWVLTApr162)
408-408 A1 --- Comm Comments regarding the fit:
i=isolated, b=blended
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 08-Nov-2017