J/ApJ/886/100 High-mass white dwarfs in Gaia DR2 (Cheng+, 2019)
A cooling anomaly of high-mass white dwarfs.
Cheng S., Cummings J.D., Menard B.
<Astrophys. J. 886, 100 (2019)>
=2019ApJ...886..100C 2019ApJ...886..100C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, white dwarf ; Stars, masses ; Stars, ages
Keywords: Bayesian statistics - Hertzsprung-Russell diagram -
Milky Way disk - stellar kinematics - stellar ages - white dwarf stars
Abstract:
Revealed by Gaia DR2, the Q branch is a narrow and prominent branch of
white dwarf overdensity on the H-R diagram. We find that there are
significantly more fast-moving white dwarfs on the Q branch, which
have very old true ages but young photometric ages. This age
discrepancy suggests a cooling anomaly in some white dwarfs on the Q
branch, posing a challenge to current white dwarf cooling models.
We tabulate the information of nearby high-mass white dwarfs (d<250,
1.08<m_WD<1.23), which is used to investigate the Q branch and its
physical origin in Cheng et al. (2019). This table contains the WD
name, photometry and astrometry from Gaia DR2, H-R diagram
coordinates and transverse velocity that we derive, and spectral
information from Montreal White Dwarf Database (MWDD).
Description:
The values in these tables are based on Gaia DR2 and the Montreal
White Dwarf Database (MWDD, http://www.montrealwhitedwarfdatabase.org).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
catalog.dat 767 1066 Nearby high-mass white dwarfs catalog
--------------------------------------------------------------------------------
See also:
J/A+A/625/A87 : Ultra-massive white dwarfs evolution models
(Camisassa+, 2019)
J/MNRAS/482/4570 : Gaia DR2 white dwarf candidates (Gentile Fusillo+, 2019)
http://www.montrealwhitedwarfdatabase.org : MWDD Home Page
Byte-by-byte Description of file: catalog.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 22 A22 --- Name White dwarf name (Whitedwarfname) (1)
24- 42 I19 --- Source Gaia DR2 source id (source_id) (2)
44- 64 F21.17 deg RAdeg Gaia right ascension (ICRS) at Ep=2015.15
(ra) (2)
66- 86 F21.17 deg DEdeg Gaia declination (ICRS) at Ep=2015.15
(dec) (2)
88-106 F19.16 mas Plx Gaia parallax (parallax) (2)
108-127 F20.18 mas e_Plx Gaia parallax error (parallax_error) (2)
129-153 F25.20 mas/yr pmRA proper motion in RA, pmRA*cosDE (pmra) (2)
155-177 F23.18 mas/yr pmDE proper motion in DE (pmdec) (2)
179-198 F20.18 mas epsi Excess noise of the source
(astrometricexcessnoise) (2)
200-210 F11.9 mas amax The longest semi-major axis of the 5-d error
ellipsoid (astrometricsigma5dmax) (2)
212-231 F20.14 e-/s FG G-band mean flux (photgmean_flux) (2)
233-251 F19.16 e-/s e_FG Error on G-band mean flux
(photgmeanfluxerror) (2)
253-261 F9.6 mag Gmag Gaia G-band magnitude (photgmean_mag) (2)
263-282 F20.14 e-/s FBP Error on the integrated BP mean flux
(photbpmean_flux) (2)
284-303 F20.16 e-/s e_FBP Error on the integrated BP mean flux
(photbpmeanfluxerror) (2)
305-314 F10.7 mag BPmag Gaia BP-band magnitude (photbpmean_mag) (2)
316-334 F19.14 e-/s FRP Mean flux in the integrated RP band
(photrpmean_flux) (2)
336-354 F19.16 e-/s e_FRP Error on the integrated RP mean flux
(photrpmeanfluxerror) (2)
356-364 F9.6 mag RPmag Gaia RP-band magnitude (photrpmean_mag) (2)
366-374 F9.7 --- E(BR/RP) BP/RP excess factor
(photbprpexcessfactor) (2)
376-395 F20.16 deg GLON Galactic longitude (l) (2)
397-418 F22.18 deg GLAT Galactic latitude (b) (2)
420-441 F22.19 mag BP-RP Gaia BP-RP colour index (bp_rp) (2)
443-460 F18.15 mag GMAG Absolute mag of Gaia G band (MG) (3)
462-482 F21.19 mag e_BP-RP Error in BP-RP (bprperror)
484-504 F21.19 mag e_GMAG Error on GMAG (MG_error) (4)
506-524 F19.17 Gyr AgeHf Photometric age assuming pure-Hydrogen
atmosphere (ageHf) (5)
526-543 F18.16 Msun MassHf Photometric mass assuming pure-Hydrogen
atmosphere (massHf) (5) (7)
545-563 F19.17 Gyr AgeHo Photometric age assuming pure-Hydrogen
atmosphere (ageHo) (5) (8)
565-582 F18.16 Msun MassHo Photometric mass assuming pure-Hydrogen
atmosphere (massHo) (5) (8)
584-602 F19.17 Gyr AgeHef ? Photometric age assuming pure-Helium
atmosphere (ageHef) (6)
604-621 F18.16 Msun MassHef ? Photometric mass assuming pure-Helium
atmosphere (massHef) (6) (7)
623-641 F19.17 Gyr AgeHeo ? Photometric age assuming pure-Helium
atmosphere (ageHeo) (6) (8)
643-660 F18.16 Msun MassHeo ? Photometric mass assuming pure-Helium
atmosphere (massHeo) (6) (8)
662-684 F23.18 km/s vL Transverse velocity in Galactic longitude
(vL) (9)
686-708 F23.18 km/s vB Transverse velocity in Galactic latitude
(vB) (9)
710-719 A10 --- MWDDspT ? Spectral type (MWDD_spectype) (10) (11)
721-749 A29 --- MWDDwdid ? useful for search in MWDD (MWDD_wdid) (10)
751-761 A11 --- MWDDwdname ? useful for search in MWDD
(MWDD_wdname) (10)
763-765 A3 --- MWDDismag ? Is it magnetic? (MWDD_ismag) (10)
767 A1 --- Region [ELQ] Region on HDR (region on HRD) (12)
--------------------------------------------------------------------------------
Note (1): Given by Gentile-Fusillo et al. (2019, Cat. J/MNRAS/482/4570).
Note (2): Columns in Gaia Data Release 2.
Note (3): Calculated by GMAG=Gmag+5log10(Plx/mas)-10.
Note (4): Calculated from the astrometric and photometric standard deviations
Note (5): Assuming pure-Hydrogen atmosphere, denoted by "H".
A public tool to convert the H-R diagram coordinate to white dwarf parameters
(age, mass, etc.,) can be found on my github:
https://github.com/SihaoCheng/WD_models
Note (6): Assuming pure-Helium atmosphere, denoted by "He".
Note (7): Using the cooling models of C/O white dwarfs (Fontaine et al.,
2001PASP..113..409F 2001PASP..113..409F), denoted by "f".
Note (8): For m_WD>1.05 Msun, using the cooling models of O/Ne WD (Camisassa et
al., 2019, Cat. J/A+A/625/A87), denoted by "o".
Note (9): The velocity relative to the center of the velocity ellipsoid, i.e.,
the observed transverse velocity plus corrections for the solar motion,
asymmetric drift (using the cooling age), and Oort constants.
Note (10): Columns from the Montreal white dwarf database (MWDD,
http://www.montrealwhitedwarfdatabase.org/tables-and-charts.html).
Note (11): CND means "can not determine".
Note (12): Code as follows:
E = early
Q = Q branch
L = late
See our paper for the exact definition.
--------------------------------------------------------------------------------
Acknowledgements:
Sihao Cheng, s.cheng(at)jhu.edu
(End) Patricia Vannier [CDS] 03-Sep-2019