J/A+A/629/A139 Closest stars to the Sun within 50pc catalog (Torres+, 2019)
Galactic tide and local stellar perturbations on the Oort cloud:
creation of interstellar comets.
Torres S., Cai M.X., Brown A.G.A., Zwart S.P.
<Astron. Astrophys. 629, A139 (2019)>
=2019A&A...629A.139T 2019A&A...629A.139T (SIMBAD/NED BibCode)
ADC_Keywords: Stars, nearby ; Stars, distances
Keywords: Oort Cloud - comets: general - stars: kinematics and dynamics -
solar neighborhood
Abstract:
Comets in the Oort cloud evolve under the influence of internal and
external perturbations, such as giant planets, stellar passages, and
the Galactic gravitational tidal field. We aim to study the dynamical
evolution of the comets in the Oort cloud, accounting for the
perturbation of the Galactic tidal field and passing stars. We base
our study on three main approaches; analytic, observational, and
numerical. We first construct an analytical model of stellar
encounters. We find that individual perturbations do not modify the
dynamics of the comets in the cloud unless very close (<0.5pc)
encounters occur. Using proper motions, parallaxes, and radial
velocities from Gaia DR2 and combining them with the radial velocities
from other surveys, we then construct an astrometric catalogue of the
14659 stars that are within 50pc of the Sun. For all these stars we
calculate the time and distance of closest approach to the Sun. We
find that the cumulative effect of relatively distant (≤1pc)
passing stars can perturb the comets in the Oort cloud. Finally, we
study the dynamical evolution of the comets in the Oort cloud under
the influence of multiple stellar encounters from stars that pass
within 2.5 pc of the Sun and the Galactic tidal field over ±10Myr.
We use the Astrophysical Multipurpose Software Environment (AMUSE),
and the GPU-accelerated direct N-body code ABIE. We considered two
models for the Oort cloud, compact (a≤0.25pc) and extended
(a≤0.5pc). We find that the cumulative effect of stellar encounters
is the major perturber of the Oort cloud for a compact configuration
while for the extended configuration the Galactic tidal field is the
major perturber. In both cases the cumulative effect of distant
stellar encounters together with the Galactic tidal field raises the
semi-major axis of ∼1.1% of the comets at the edge of the Oort cloud
up to interstellar regions (a>0.5pc) over the 20Myr period considered.
This leads to the creation of transitional interstellar comets (TICs),
which might become interstellar objects due to external perturbations.
This raises the question of the formation, evolution, and current
status of the Oort cloud as well as the existence of a "cloud" of
objects in the interstellar space that might overlap with our Oort
cloud, when considering that other planetary systems should undergo
similar processes leading to the ejection of comets.
Description:
Each line contains the stellar, astrometric parameters from Gaia DR2,
RAVE DR5 GALAH DR2, LAMOST DR3, APOGEE DR14, and XHIP, for each star
that is closer than 50pc from Sun.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 1114 73246 Catalogue of closest stars to the Sun within 50pc
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Seq [0/73245] Sequential number
7- 25 A19 --- SolID Solution Identifier (solution_id)
27- 54 A28 --- DR2Name Unique source designation (Gaia DR2
NNNNNNNNNNNNNNNNNNN) (designation)
56- 74 I19 --- Source Unique source identifier (source_id)
76- 81 F6.1 yr Epoch [2015.5] Reference epoch (ref_epoch)
83- 104 F22.18 deg RAdeg Barycentric right ascension (ICRS)
at Ep=2015.5 (ra)
106- 125 F20.18 mas e_RAdeg Standard error of right ascension
(e_RA*cosDE) (ra_error)
127- 148 F22.18 deg DEdeg Barycentric declination (ICRS)
at Ep=2015.5 (dec)
150- 169 F20.18 mas e_DEdeg Standard error of declination (dec_error)
171- 190 F20.15 mas Plx ? Absolute stellar parallax (parallax)
192- 211 F20.18 mas e_Plx ? Standard error of parallax
(parallax_error)
213- 234 F22.16 --- RPlx ? Parallax divided by its error
(parallaxovererror)
236- 260 F25.19 mas/yr pmRA ? Proper motion in right ascension
direction (pmRA*cosDE) (pmra)
262- 281 F20.18 mas/yr e_pmRA ? Standard error of proper motion in
right ascension direction (pmra_error)
283- 308 F26.20 mas/yr pmDE ? Proper motion in declination direction
(pmdec)
310- 329 F20.18 mas/yr e_pmDE ? Standard error of proper motion in
declination direction (pmdec_error)
331- 353 E23.19 --- RADEcor Correlation between right ascension and
declination (radeccorr)
355- 377 E23.19 --- RAPlxcor ? Correlation between right ascension and
parallax (raparallaxcorr)
379- 401 E23.19 --- RApmRAcor ? Correlation between right ascension and
proper motion in right ascension
(rapmracorr)
403- 425 E23.19 --- RApmDEcor ? Correlation between right ascension and
proper motion in declination
(rapmdeccorr)
427- 449 E23.19 --- DEPlxcor ? Correlation between declination and
parallax (decparallaxcorr)
451- 473 E23.19 --- DEpmRAcor ? Correlation between declination and
proper motion in right ascension
(decpmracorr)
475- 497 E23.19 --- DEpmDEcor ? Correlation between declination and
proper motion in declination
(decpmdeccorr)
499- 521 E23.19 --- PlxpmRAcor ? Correlation between parallax and
proper motion in right ascension
(parallaxpmracorr)
523- 545 E23.19 --- PlxpmDEcor ? Correlation between parallax and
proper motion in declination
(parallaxpmdeccorr)
547- 569 E23.19 --- pmRApmDEcor ? Correlation between proper motion in
right ascension and proper motion in
declination (pmrapmdeccorr)
571- 595 F25.20 --- gofAL Goodness of fit statistic of model wrt
along-scan observations
(astrometricgofal)
597- 601 A5 --- Dup Source with duplicate sources
(duplicated_source)
603- 621 F19.16 mag Gmag G-band mean magnitude (Vega)
(photgmean_mag)
623- 641 F19.16 mag BPmag ? Integrated BP mean magnitude (Vega)
(photbpmean_mag)
643- 661 F19.16 mag RPmag ? Integrated RP mean magnitude (Vega)
(photrpmean_mag)
663- 684 E22.18 mag BP-RP ? BP-RP colour
(photBpMeanMag-photRMeanMag) (bp_rp)
686- 707 E22.18 mag BP-G ? BP-G colour
(photBpMeanMag-photGMeanMag) (bp_g)
709- 730 E22.18 mag G-RP ? G-RP colour
(photGMeanMag-photRpMeanMag) (g_rp)
732- 755 F24.19 km/s RV ? Spectroscopic radial velocity in the
solar barycentric reference frame
(radial_velocity)
757- 776 F20.17 km/s e_RV ? Radial velocity error
(radialvelocityerror)
778- 779 I2 --- o_RV Number of transits used to compute
radial velocity (rvnbtransits)
781- 786 F6.1 K Tefftemp ? Teff of the template used to compute
radial velocity (rvtemplateteff)
788- 790 F3.1 [cm/s2] loggtemp ? logg of the template used to compute
radial velocity (rvtemplatelogg)
792- 796 F5.2 --- [Fe/H]temp ? Fe/H of the template used to compute
radial velocity (rvtemplatefe_h)
798- 810 A13 --- Var Photometric variability flag
(photvariableflag)
812- 834 F23.19 deg GLON Galactic longitude (l)
836- 858 F23.19 deg GLAT Galactic latitude (b)
860- 882 F23.19 deg ELON Ecliptic longitude (ecl_lon)
884- 906 F23.19 deg ELAT Ecliptic latitude (ecl_lat)
908- 925 F18.13 K Teff ? Stellar effective temperature
(estimate from Apsis-Priam) (teff_val)
927- 944 F18.13 K b_Teff ? Uncertainty (lower) on Teff estimate
from Apsis-Priam (16th percentile)
(teffpercentilelower)
946- 963 F18.13 K B_Teff ? Uncertainty (upper) on Teff estimate
from Apsis-Priam (84th percentile)
(teffpercentileupper)
965- 984 F20.18 mag AG ? Estimate of extinction in the G band
from Apsis-Priam (agval)
986-1005 F20.18 mag b_E(BP-RP) ? Uncertainty (lower) on E(BP-RP)
estimate from Apsis-Priam
(16th percentile)
(ebpminrppercentile_lower)
1007-1028 F22.18 solLum Lum ? Esimate of luminosity from Apsis-FLAME
(lum_val)
1030-1048 F19.16 pc rh Perihelion distance (rh)
1050-1072 A23 Myr tph Time at closest approach (tph)
1074-1093 F20.17 pc dph ? Distance at closest approach (dph)
1095-1114 F20.16 km/s vtot ? Total velocity of the stars at closest
approach (v_tot)
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Acknowledgements:
Santiago Torres, storres(at)strw.leidenuniv.nl
(End) Patricia Vannier [CDS] 05-Sep-2019