J/MNRAS/480/5099 Multiplicity of disc-bearing stars (Kuruwita+, 2018)
Multiplicity of disc-bearing stars in Upper Scorpius and Upper Centaurus-Lupus.
Kuruwita R.L., Ireland M., Rizzuto A., Bento J., Federrath C.
<Mon. Not. R. Astron. Soc., 480, 5099-5112 (2018)>
=2018MNRAS.480.5099K 2018MNRAS.480.5099K (SIMBAD/NED BibCode)
ADC_Keywords: Radial velocities ; Binaries, spectroscopic ;
Stars, pre-main sequence ; Optical
Keywords: techniques: radial velocities - protoplanetary discs -
binaries: spectroscopic - stars: formation - stars: pre-main-sequence
Abstract:
We present observations of disc-bearing stars in Upper Scorpius (US)
and Upper Centaurus-Lupus (UCL) with moderate resolution spectroscopy
in order to determine the influence of multiplicity on disc
persistence after ∼5-20Myr. Discs were identified using infrared (IR)
excess from the Wide-field Infrared Survey Explorer (WISE) survey. Our
survey consists of 55 US members and 28 UCL members, using spatial and
kinematic information to assign a probability of membership. Spectra
are gathered from the ANU 2.3m telescope using the Wide Field
Spectrograph (WiFeS) to detect radial velocity variations that
indicate the presence of a companion. We identify two double-lined
spectroscopic binaries, both of which have strong IR excess. We find
the binary fraction of disc-bearing stars in US and UCL for periods up
to 20yr to be 0.06+0.07-0.02 and 0.13+0.06-0.03,
respectively. Based on the multiplicity of field stars, we obtain an
expected binary fraction of ∼0.12+0.02-0.01. The determined
binary fractions for disc-bearing stars do not vary significantly from
the field, suggesting that overall lifetime of discs may not differ
between single and binary star systems.
Description:
We selected candidate US and UCL members using kinematic and
photometric data from UCAC4, 2MASS, USNO-B, and APASS (Monet et al.
2003AJ....125..984M 2003AJ....125..984M, Cat. I/284; Skrutskie et al. 2006AJ....131.1163S 2006AJ....131.1163S,
Cat. VII/233; Henden et al. 2012; Zacharias et al.
2013AJ....145...44Z 2013AJ....145...44Z, Cat. I/322) using the Bayesian membership
selection method of Rizzuto et al. (2011MNRAS.416.3108R 2011MNRAS.416.3108R, Cat.
J/MNRAS/416/3108) and Rizzuto et al. (2015MNRAS.448.2737R 2015MNRAS.448.2737R, Cat.
J/MNRAS/448/2737), which uses kinematic and spatial information to
assign membership probabilities. We also used the photometry and a
15Myr pre-main sequence isochrone (Siess, Dufour & Forestini
2000A&A...358..593S 2000A&A...358..593S) to estimate each candidate member's distance.
This selection was magnitude limited, and covered all stars in the
UCAC4 catalogue with 10<V<16, and comprised of several thousand
candidate members with membership probability greater than 25 per
cent.
To obtain spectroscopic data to determine the radial velocities of our
targets, we used the Wide Field Spectrograph (WiFeS) (Dopita et al.
2007Ap&SS.310..255D 2007Ap&SS.310..255D). WiFeS is an integral field spectrograph on the
Australian National University 2.3m Telescope at Siding Spring
Observatory. We use this instrument to search for RV variation
overtime for our targets. The instrument consists of a blue camera
with spectral range 329-558nm and red camera with spectral range
529-912nm.
Data for our targets were collected from 2013 June to 2017 July. Our
observations include Ne-Ar arc exposures every 15-30 min to
characterize the wavelength scale variation of the instrument over the
night due to temperature fluctuations. The WiFeS R ∼7000 grating is
used to perform RV measurements. We observe RV standards with
well-characterized velocities of various spectral types.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 32 27 RV standards used as templates to obtain radial
velocities of our observed targets
tablea1.dat 93 84 Magnitudes of our targets
tablea3.dat 86 324 Full list of objects observed in this survey
with each epoch of data
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Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Radial velocity standards ID (1)
10- 16 F7.3 km/s RV Radial velocity
18- 25 A8 --- SpType Spectral type
27 A1 --- r_SpType Reference on SpType (2)
29- 32 F4.2 Msun Mass Approximate mass of the star (3)
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Note (1): RV standards used as templates to obtain radial velocities of our
observed targets. Standards are selected from the Nidever et al.
(2002ApJS..141..503N 2002ApJS..141..503N, Cat. J/ApJS/141/503) and Soubiran et al.
(2013A&A...552A..64S 2013A&A...552A..64S, Cat. J/A+A/552/A64) catalogues
Note (2): References as follows:
a = Houk (1982mcts.book.....H 1982mcts.book.....H, Cat. III/51)
b = Keenan & McNeil (1989ApJS...71..245K 1989ApJS...71..245K, Cat. III/150)
c = Gray et al. (2006AJ....132..161G 2006AJ....132..161G, Cat. J/AJ/132/161)
d = Houk & Smith-Moore (1988mcts.book.....H 1988mcts.book.....H, Cat. III/133)
e = Houk & Swift (1999MSS...C05....0H 1999MSS...C05....0H, Cat. III/214)
f = Henry et al. (2002AJ....123.2002H 2002AJ....123.2002H)
g = Stephenson (1986AJ.....92..139S 1986AJ.....92..139S)
h = Alonso-Floriano et al. (2015A&A...577A.128A 2015A&A...577A.128A, Cat. J/A+A/577/A128)
i = Kirkpatrick, Henry & McCarthy (1991ApJS...77..417K 1991ApJS...77..417K)
j = Davison et al. (2015AJ....149..106D 2015AJ....149..106D)
Note (3): The approximate masses are derived from the Baraffe et al.
(2015A&A...577A..42B 2015A&A...577A..42B) pre-main sequence evolution models based on
spectral type at age log10(tage)∼7.1
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Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Target name
18- 19 I2 h RAh Right ascension (J2000)
21- 22 I2 min RAm Right ascension (J2000)
24- 28 F5.2 s RAs Right ascension (J2000)
30 A1 --- DE- Declination sign (J2000)
31- 32 I2 deg DEd Declination (J2000)
34- 35 I2 arcmin DEm Declination (J2000)
37- 40 F4.1 arcsec DEs Declination (J2000)
42- 47 F6.3 mag Jmag 2MASS J-band magnitude
49- 54 F6.3 mag Kmag 2MASS K-band magnitude
56- 60 F5.3 mag W4mag WISE W4 (22um) band magnitude
62- 71 F10.7 mag Gmag ? Gaia G-band magnitude
73- 82 F10.7 mag BPmag ? Gaia BP-band magnitude
84- 93 F10.7 mag RPmag ? Gaia RP-band magnitude
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Target name
18- 20 A3 --- Region Region name
22- 23 I2 h RAh Right ascension (J2000)
25- 26 I2 min RAm Right ascension (J2000)
28- 32 F5.2 s RAs Right ascension (J2000)
34 A1 --- DE- Declination sign (J2000)
35- 36 I2 deg DEd Declination (J2000)
38- 39 I2 arcmin DEm Declination (J2000)
41- 44 F4.1 arcsec DEs Declination (J2000)
46- 53 A8 --- SpTypetemp Spectral type of the preferred template used
for each object
55- 65 F11.5 d MJD Modified Julian Date JD-2400000.5
67- 72 F6.2 km/s RV Radial velocity
74- 78 F5.2 km/s e_RV Error on RV
80- 86 F7.2 0.1nm EWHa Equivalent width of Hα line
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 30-May-2022