J/A+A/645/A30 SB updated census in SACY sample (Zuniga-Fernandez+, 2021)
Search for associations containing young stars (SACY).
VIII. An updated census of spectroscopic binary systems exhibiting hints of
non-universal multiplicity among their associations
Zuniga-Fernandez S., Bayo A., Elliott P., Zamora C., Corvalan G.,
Haubois X., Corral-Santana J.M., Olofsson J., Huelamo N., Sterzik M.F.,
Torres C.A.O., Quast G.R., Melo C.H.F.
<Astron. Astrophys. 645, A30 (2021)>
=2021A&A...645A..30Z 2021A&A...645A..30Z (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, spectroscopic ; Stars, pre-main sequence
Keywords: binaries: spectroscopic - stars: pre-main sequence -
stars: formation - techniques: radial velocities -
techniques: spectroscopic
Abstract:
Nearby young associations offer one of the best opportunities for a
detailed study of the properties of young stellar and substellar
objects thanks to their proximity (<200pc) and age (∼5-150Myr).
Previous works have identified spectroscopic (<5au) binaries, close
(5-1000au) visual binaries, and wide or extremely wide (1000-100000au)
binaries in the young associations. Inmost of the previous analyses,
single-lined spectroscopic binaries (SB1) were identified based on
radial velocities variations. However, this apparent variation may also
be caused by mechanisms unrelated to multiplicity.
We seek to update the spectroscopy binary fraction of the Search for
Associations Containing Young stars (SACY) sample, taking into
consideration all possible biases in our identification of binary
candidates, such as activity and rotation.
Using high-resolution spectroscopic observations, we produced ∼1300
cross-correlation functions (CCFs) to disentangle the previously
mentioned sources of contamination. The radial velocity values we
obtained were cross-matched with the literature and then used to revise
and update the spectroscopic binary (SB) fraction in each object of
the SACY association. In order to better describe the CCF profile, we
calculated a set of high-order cross-correlation features to determine
the origin of the variations in radial velocities.
We identified 68 SB candidates from our sample of 410 objects. Our
results hint that at the possibility that the youngest associations
have a higher SB fraction. Specifically, we found
sensitivity-corrected SB fractions of 22+15-11% for ε Cha,
31+16-14% for TW Hya and 32+9-8% for β Pictoris, in
contrast to the five oldest associations we have sampled (∼35-125Myr)
which are ∼10% or lower. This result seems independent of the
methodology used to asses membership to the associations.
The new CCF analysis, radial velocity estimates, and SB candidates are
particularly relevant for membership revision of targets in young
stellar associations. These targets would be ideal candidates for
follow-up campaigns using high-resolution techniques to confirm
binarity, resolve orbits, and, ideally, calculate dynamical masses.
Additionally, if the results on the SB fraction in the youngest
associations were confirmed, it could hint at a non-universal
multiplicity among SACY associations.
Description:
We obtained spectra taken with the Ultraviolet and Visual Echelle
Spectrograph (UVES; λ/{DELTA}λ∼40000 with a 1" slit) in
Paranal, Chile. These observations came from three of our observing
campaigns, taken between 2015 and 2016. We also added data retrieved
from the ESO phase 3 public archive.
We present an update for the SB census for the associations within
SACY. Our study is based on new observational data (as well as
literature and archival data), as well as new criteria to identify
these tight binaries. We have estimated radial and rotational velocity
for 1375 spectra using CCFs and compiled 400 RV measurements from the
literature (including Gaia DR2, Gaia Collaboration et al. 2018, Cat.
I/345). Our RVs and vsini estimates are in good agreement with
previously published values, following a 1:1 relation with values from
the literature (for targets that are not identified as a multiple
systems), demonstrating that our CCF analysis is robust. Further
robustness is provided by the fact that we have recovered the
84+11-8% of previously known multiple systems.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
sacysb.dat 312 415 Sample presented in this work (table G4)
rvindi.dat 110 2379 Individual radial velocities values calculated
in this work and compiled from the
literature/Gaia DR2 for 590 stars (table G1)
rotvel.dat 60 1515 Individual rotational velocity values calculated
in this work and compiled from literature
for 483 stars (table G2)
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/A+A/460/695 : Search for Associations Containing Young stars
(Torres+, 2006)
J/A+A/508/833 : SACY III. Li abundances (da Silva+, 2009)
J/MNRAS/431/1005 : SACY IV. IC 2391 and Argus young stars (de Silva+, 2013)
J/A+A/568/A26 : SACY V. Multiple systems (Elliott+, 2014)
J/A+A/580/A88 : SACY VI. Stellar multiplicity in 3-1000AU (Elliott+, 2015)
J/A+A/590/A13 : SACY VII. New candidate members in young associations
(Elliott+, 2016)
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Byte-by-byte Description of file: sacysb.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 22 A22 --- Name Simbad identifier
24- 33 F10.6 deg RAdeg Right ascension (J2000)
35- 44 F10.6 deg DEdeg Declination (J2000)
46- 52 F7.3 km/s RV-med-ccf ? Median RV from our CCF
54- 60 F7.4 km/s s_RV-med-ccf ? Standard deviation in RV from our CCF
62- 67 F6.3 km/s vsini-med-ccf ? Median vsini from our CCF
69- 75 F7.4 km/s s_vsini-med-ccf ? Standard deviation in vsini from our CCF
77- 78 I2 --- o_RV-med-ccf ? Number of observation (CCF)
80- 86 F7.3 km/s RV-med-lit ? Median RV from literature
88- 94 F7.4 km/s s_RV-med-lit ? Standard deviation in RV from literature
96- 97 I2 --- o_RV-med-lit ? Number of observation (RV literature)
99-104 F6.3 km/s vsini-med-lit ? Median vsini from literature
106-112 F7.4 km/s s_vsini-med-lit ? Standard deviation in vsini
from literature
114-115 I2 --- o_vsini-med-lit ? Number of observation
(vsini literature)
117-123 F7.4 d Per ? Period from light curve
125-131 F7.4 d e_Per ? Period uncertainty
133-154 E22.15 --- FAP ? False alarm probability
156-166 F11.4 --- P-MAD ? Mean average deviation (phased LC)
168-178 F11.4 --- R-MAD ? MAD (residuals of phased LC)
180-189 F10.6 --- P-MAD/R-MAD ? Ratio phased-MAD and residual-MAD
191-194 A4 --- Inst LC measurement instrument (TESS or K2)
196-197 I2 --- TESSsector ? TESS sector
199-207 I9 --- TESS/K2 ? TESS or K2 identifier
209-217 A9 --- NTESS Number of sources in TESS aperture
219-225 F7.4 mag MindGmag ? Minimun delta Mag in TESS aperture
227-228 A2 --- LCnotes [N/ NG TG] Light curves notes
230-236 A7 --- LCqflag Light curves quality flag
238-256 I19 --- GaiaDR2 ? Gaia DR2 source_id
258-261 F4.2 Msun Mass ? Mass
263-266 A4 --- SpType ? Spectral type
268-270 A3 --- SACYMG Best moving group match from SACY method
272-276 F5.3 --- SACYprob ? Membership probability from SACY method
278-283 A6 --- BANMG Best moving group match from BANYAN
285-292 F8.5 --- BANprob ? Membership probability from BANYAN
294-312 A19 --- Notes Notes on SB candidates
--------------------------------------------------------------------------------
Byte-by-byte Description of file: rvindi.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- Name Simbad identifier
25- 34 F10.6 deg RAdeg Right ascension (J2000)
36- 45 F10.6 deg DEdeg Declination (J2000)
47- 53 F7.3 km/s RV Radial velocity
55- 65 F11.8 km/s e_RV Radial velocity uncertainty
67- 73 F7.1 d MJD ? Observation date
75- 81 F7.3 --- BIS ? Bisector inverse slope
83- 91 F9.3 --- bb ? Bisector slope
93- 99 F7.3 --- cb ? Curvature
101-105 A5 --- Inst Observation instrument
107-110 A4 --- r_RV Reference code (1)
--------------------------------------------------------------------------------
Note (1): Reference codesas follows:
ZF20 = this work
SC12 = Schlieder et al. (2012AJ....144..109S 2012AJ....144..109S)
SH12 = Shkolnik et al. (2012ApJ...758...56S 2012ApJ...758...56S, Cat. J/ApJ/758/56)
TO06 = Torres et al. (2006A&A...460..695T 2006A&A...460..695T, Cat. J/A+A/460/695)
LO06 = Lopez-Santiago et al. (2006ApJ...643.1160L 2006ApJ...643.1160L)
RO13 = Rodriguez et al. (2013ApJ...774..101R 2013ApJ...774..101R)
MA10 = Maldonado et al. (2010A&A...521A..12M 2010A&A...521A..12M, Cat. J/A+A/521/A12)
MO13 = Moor et al. (2013MNRAS.435.1376M 2013MNRAS.435.1376M)
RE09 = Reiners & Basri (2009ApJ...705.1416R 2009ApJ...705.1416R, Cat. 2009ApJ...705.1416R 2009ApJ...705.1416R)
GO06 = Gontcharov (2006AstL...32..759G 2006AstL...32..759G, Cat. III/252)
MA14 = Malo et al. (2014ApJ...788...81M 2014ApJ...788...81M, Cat. J/ApJ/788/81)
KR14 = Kraus et al. (2014AJ....147..146K 2014AJ....147..146K,Cat. J/AJ/147/146)
MO01b = Montes et al. (2001A&A...379..976M 2001A&A...379..976M, Cat. J/A+A/379/976)
MO02 = Mochnacki et al. (2002AJ....124.2868M 2002AJ....124.2868M)
BA12 = Bailey et al. (2012ApJ...749...16B 2012ApJ...749...16B)
DE15 = Desidera et al. (2015A&A...573A.126D 2015A&A...573A.126D, Cat. J/A+A/573/A126)
GDR2 = Gaia DR2, Gaia Collaboration et al. (2018, Cat. I/345)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: rotvel.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 22 A22 --- Name Simbad identifier
24- 33 F10.6 deg RAdeg Right ascension (J2000)
35- 44 F10.6 deg DEdeg Declination (J2000)
46- 51 F6.2 km/s vsini Rotational velocity
53- 55 F3.1 km/s e_vsini Rotational velocity uncertainty
57- 60 A4 --- r_vsini Reference code (1)
--------------------------------------------------------------------------------
Note (1): Reference codes as follows:
ZF20 = this work
SC12 = Schlieder et al. (2012AJ....144..109S 2012AJ....144..109S)
TO06 = Torres et al. (2006A&A...460..695T 2006A&A...460..695T, Cat. J/A+A/460/695)
MA14 = Malo et al. (2014ApJ...788...81M 2014ApJ...788...81M, Cat. J/ApJ/788/81)
BA12 = Bailey et al. (2012ApJ...749...16B 2012ApJ...749...16B)
DE15 = Desidera et al. (2015A&A...573A.126D 2015A&A...573A.126D, Cat. J/A+A/573/A126)
--------------------------------------------------------------------------------
Acknowledgements:
Sebastian Zuniga-Fernandez sebastian.zuniga(at)postgrado.uv.cl
References:
Torres et al., Paper I 2006A&A...460..695T 2006A&A...460..695T, Cat. J/A+A/460/695
Viana Almeida et al., Paper II 2009A&A...501..965V 2009A&A...501..965V
da Silva et al., Paper III 2009A&A...508..833D 2009A&A...508..833D, Cat. J/A+A/508/833
de Silva et al., Paper IV 2013MNRAS.431.1005D 2013MNRAS.431.1005D, Cat. J/MNRAS/431/1005
Elliott et al., Paper V 2014A&A...568A..26E 2014A&A...568A..26E, Cat. J/A+A/568/A26
Elliott et al., Paper VI 2014A&A...580A..88E 2014A&A...580A..88E, Cat. J/A+A/580/A88
Elliott et al., Paper VII 2016A&A...590A..13E 2016A&A...590A..13E, Cat. J/A+A/590/A13
(End) Patricia Vannier [CDS] 05-Nov-2020