J/AJ/148/48 CHARA obs. of omega And, HD 178911, xi Cep (Farrington+, 2014)
Separated fringe packet observations with the CHARA array.
II. ω Andromeda, HD 178911, and ξ Cephei.
Farrington C.D., ten Brummelaar T.A., Mason B.D., Hartkopf W.I.,
Mourard D., Moravveji E., McAlister H.A., Turner N.H., Sturmann L.,
Sturmann J.
<Astron. J., 148, 48 (2014)>
=2014AJ....148...48F 2014AJ....148...48F
ADC_Keywords: Stars, double and multiple ; Binaries, spectroscopic ;
Interferometry
Keywords: binaries: close - binaries: spectroscopic - infrared: stars -
stars: individual: (* ome And,HD 178911,* ksi Cep) -
techniques: high angular resolution - techniques: interferometric
Abstract:
When observed with optical long-baseline interferometers, components
of a binary star that are sufficiently separated produce their own
interferometric fringe packets; these are referred to as separated
fringe packet (SFP) binaries. These SFP binaries can overlap in
angular separation with the regime of systems resolvable by speckle
interferometry at single, large-aperture telescopes and can provide
additional measurements for preliminary orbits lacking good phase
coverage, help constrain elements of already established orbits, and
locate new binaries in the undersampled regime between the bounds of
spectroscopic surveys and speckle interferometry. In this process, a
visibility calibration star is not needed, and the SFPs can provide an
accurate vector separation. In this paper, we apply the SFP approach
to ω Andromeda, HD 178911, and ξ Cephei with the CLIMB
three-beam combiner at the CHARA Array. For these systems we determine
component masses and parallax of 0.963±0.049M☉ and
0.860±0.051M☉ and 39.54±1.85mas for ω Andromeda, for
HD 178911 of 0.802±0.055M☉and 0.622±0.053M☉with
28.26±1.70mas, and masses of 1.045±0.031M☉and
0.408±0.066M☉and 38.10±2.81mas for ξ Cephei.
Description:
Data were routinely taken on the CHARA Array's three largest baselines
(S1-E1-W1) and other intermediate baselines when the preferred
telescopes were assigned to other simultaneous observing experiments.
A list of observations for ω Andromeda, HD 178911, and ξ
Cephei taken with the CHARA Array, along with baselines used, is given
in Table1.
Before 2009, observations for the Separated Fringe Packet (SFP)
program were taken as described in PaperI (Farrington et al.,
2010AJ....139.2308F 2010AJ....139.2308F) with the CHARA Classic two-beam combiner as
described by ten Brummelaar et al. (2005ApJ...628..453T 2005ApJ...628..453T). All
observations after 2009 were taken with the CHARA CLIMB IR pupil-plane
three-beam combiner (ten Brummelaar et al., 2013JAI.....240004T) also
through the K' filter. The time span between observing sessions ranged
from as little as a week to more than a year. Orbits for these systems
were determined with combined spectroscopic/interferometric solutions
as described in Tokovinin (1992ASPC...32..573T 1992ASPC...32..573T, 1993AstL...19...73T 1993AstL...19...73T)
with all available CHARA, published speckle interferometry data
(Hartkopf et al., 2001AJ....122.3480H 2001AJ....122.3480H), and spectroscopic orbits.
Objects:
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RA (ICRS) DE Designation(s) (Period)
-------------------------------------------------------------------
01 27 39.38 +45 24 24.1 omega And = ADS 1152 AB (P=254.9003)
19 09 04.39 +34 36 01.6 HD 178911 = ADS 12101 A (P=1296.984)
22 03 47.45 +64 37 40.7 xi Cep = ADS 15591 (P=819.9402)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 78 260 CHARA Separated Fringe Packet (SFP) observations
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See also:
B/wds : The Washington Visual Double Star Catalog (Mason+ 2001-2014)
J/ApJ/683/424 : CHARA observations of 3 late-type stars (Boyajian+, 2008)
J/AJ/119/3084 : ICCD speckle obs. of binary stars. XXIII. (Hartkopf+, 2000)
J/ApJS/59/95 : Visual multiples. VIII. (Abt+, 1985)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name System name (HD 178911, ω And, ξ Cep)
13- 14 I2 --- Set [1/29] Observation set number (1)
16- 26 F11.5 d MJD Modified Julian Date of the observation
28- 33 F6.2 m Base [100/400]? Projected baseline length
35- 38 A4 --- f_Base VEGA measurement for projected baseline length (2)
40- 45 F6.2 deg PA1 [0/360]? 1-D position angle of projected baseline
(θ) (3)
47- 48 A2 --- l_Sep1 [~<] Upper limit flag on Sep1
50- 54 F5.2 mas Sep1 [5/85]? 1-D separation between peaks (ρ) (4)
56- 64 F9.4 yr Year [2005/2013]? Average Barycentric observation year
66- 71 F6.2 deg PA2 [0/360]? Average 2-D position angle of projected
baseline (θ)
73- 78 F6.2 mas Sep2 ? Average 2-D separation between peaks (ρ) (5)
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Note (1): Observation log for ω Andromeda, HD 178911, and ξ Cephei on
the CHARA Array from 2005 to 2012. Each set of vector observations (along
with the projected baseline length and epoch of observation) in Columns 3-6
were combined to create the true location of the secondary and average time
of all the data points defined in the last three columns (Year, PA2, Sep2).
Note (2): The "VEGA" measurements do not use the Separated Fringe Packet (SFP)
method but visibility modulation typical for interferometers, and thus do
not consist of 1-D vector measurements.
Note (3): At the midpoint of the five minute recording sequence.
Note (4): Of the two average fringe envelopes that have been summed over the
course of the data file (see Farrington et al., 2010AJ....139.2308F 2010AJ....139.2308F).
Note (5): Errors for all measurements in Sep2 are ∼1mas.
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History:
From electronic version of the journal
References:
Farrington et al. , Paper I, 2010AJ....139.2308F 2010AJ....139.2308F
Farrington et al. , Paper III, 2018AJ....156..144F 2018AJ....156..144F
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 21-Nov-2014