J/AJ/144/55 Infrared spectroscopy of NTTS 155808-2219 (Mace+, 2012)
Dynamical measurements of the young upper Scorpius triple NTTS 155808-2219.
Mace G.N., Prato L., Torres G., Wasserman L.H., Mathieu R.D., McLean I.S.
<Astron. J., 144, 55 (2012)>
=2012AJ....144...55M 2012AJ....144...55M
ADC_Keywords: Binaries, spectroscopic ; Stars, pre-main sequence ;
Spectroscopy ; Radial velocities
Keywords: binaries: spectroscopic - stars: evolution - stars: pre-main sequence
Abstract:
The young, low-mass, triple system NTTS 155808-2219 (ScoPMS 20) was
previously identified as a ∼17day period single-lined spectroscopic
binary (SB) with a tertiary component at 0.21arcsec. Using
high-resolution infrared spectra, acquired with NIRSPEC on Keck II,
both with and without adaptive optics (AO), we measured radial
velocities (RVs) of all three components. Reanalysis of the
single-lined visible light observations, made from 1987 to 1993, also
yielded RV detections of the three stars. Combining visible light and
infrared data to compute the orbital solution produces orbital
parameters consistent with the single-lined solution and a mass ratio
of q=0.78±0.01 for the SB. We discuss the consistency between our
results and previously published data on this system, our RV analysis
with both observed and synthetic templates, and the possibility that
this system is eclipsing, providing a potential method for the
determination of the stars' absolute masses. Over the ∼20year baseline
of our observations, we have measured the acceleration of the SB's
center of mass in its orbit with the tertiary. Long-term, AO imaging
of the tertiary will eventually yield dynamical data useful for
component mass estimates.
Description:
Spectroscopic observations of NTTS 155808-2219 were collected from
1987 June to 1993 April. Two nearly identical echelle spectrographs
were used on the Multiple Mirror Telescope on Mount Hopkins, Arizona
(prior to its conversion to a monolithic mirror), and on the 1.5m
Tillinghast reflector at the F. L. Whipple Observatory, also atop
Mount Hopkins. A single echelle order, 45Å wide, was recorded at a
central wavelength of 5188.5Å, providing a resolving power
R=λ/Δλ≃35000.
Observations were made in the IR between 2000 June and 2007 April with
the Keck II 10m telescope on Mauna Kea. All spectra have resolution
R≃30000.
Objects:
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RA (2000) DE Designation(s)
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16 01 05.19 -22 27 31.2 NTTS 155808-2219 = V* V1151 Sco
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 62 37 Visible light spectroscopic observations and
radial velocities
table3.dat 62 7 Infrared spectroscopic observations and radial
velocities
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See also:
J/ApJ/745/56 : Upper Sco members rotational velocities (Dahm+, 2012)
J/AJ/124/1144 : Orbits of 171 single-lined spectroscop. binaries (Latham, 2002)
J/A+A/376/982 : Near-IR observations of young binaries (Woitas+, 2001)
J/A+A/369/249 : T Tauri binary systems orbital motion (Woitas+, 2001)
J/AJ/120/479 : Low-mass stars in the Upper Sco association (Ardila+, 2000)
J/A+A/356/541 : T Tauri stars in the Sco-Cen OB association (Koehler+, 2000)
J/A+A/216/44 : Walraven photometry in Sco-Cen association (De Geus+, 1989)
Byte-by-byte Description of file: table[23].dat
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Bytes Format Units Label Explanations
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1- 11 A11 "Y:M:D" Date UT date of observation
13 A1 --- f_Date [ab] a = tertiary spectrum separated (1)
15- 24 F10.4 d HJD [46955.7/54221] Heliocentric Julian Date
(HJD-2400000)
26- 31 F6.2 km/s RV1 [-42/30] Radial velocity of the primary
33- 36 F4.2 km/s e_RV1 Uncertainty in RV1
38- 43 F6.2 km/s RV2 [-54/42]? Radial velocity of the secondary
45- 48 F4.2 km/s e_RV2 ? Uncertainty in RV2
50- 55 F6.2 km/s RV3 [-12/3]? Radial velocity of the tertiary
57- 62 F6.4 --- Phase Spectroscopic binary phase
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Note (1): Flag on Date as follows:
a = NIRSPEC+AO observation; SB and tertiary spectra separated;
b = NIRSPEC+AO observation; SB only.
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History:
From electronic version of the journal
(End) Sylvain Guehenneux [CDS] 07-Oct-2013