J/AJ/158/148 Photometry of beta Lyr by the BRITE satellites.II (Rucinski+, 2019)
Photometry of β Lyrae in 2018 by the BRITE satellites.
Rucinski S.M., Pigulski A., Kuschnig R., Moffat A.F.J., Popowicz A.,
Pablo H., Wade G.A., Weiss W.W., Zwintz K.
<Astron. J., 158, 148 (2019)>
=2019AJ....158..148R 2019AJ....158..148R (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Photometry ; Optical
Keywords: binaries: close - binaries: eclipsing -
stars: individual (β Lyr) - techniques: photometric
Abstract:
Observations of β Lyr in four months of 2018 by three BRIght Target
Explorer (BRITE) Constellation satellites, the red-filter BRITE-Toronto
and BRITE-Heweliusz, and the blue-filter BRITE-Lem, permitted a first,
limited look into the light-curve variability in two spectral bands. The
variations were found to be well correlated outside the innermost phases
of the primary eclipses with the blue variations appearing to have smaller
amplitudes than the red; this reduction may reflect their presumed origin
in the cooler, outer parts of the accretion disk. This result must be
confirmed with more extensive material as the current conclusions are
based on observations spanning slightly less than three orbital cycles
of the binary. The assumption of an instrumental problem and the applied
corrections made to explain the unexpectedly large amplitude of the
red-filter light curve observed with the BRITE-Toronto satellite in 2016
are fully confirmed by the 2018 results.
Description:
The new observations of β Lyrae were obtained between 2018 June 5
and October 23 using the red-filter satellites BRITE-Toronto (BTr) and
BRITE-Heweliusz (BHr), and the blue-filter satellite BRITE-Lem (BLb).
The individual exposures (three per minute) have been grouped into much
better defined satellite-orbit average data, permitting brightness
sampling at 98.4 minutes for BTr, 97.7 minutes for BHr, and 99.5 minutes
for BLb. The BTr satellite was oriented to place the β Lyr image in
a different CCD location than in 2016 to avoid the CTI-affected area that
complicated analysis of the otherwise excellent data acquired previously.
Objects:
----------------------------------------------------
RA (ICRS) DE Designation(s)
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18 50 04.80 +33 21 45.6 β Lyr = * bet Lyr
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 35 2314 The satellite-orbit, average data
table2.dat 25 274 The mean, seasonal, 2018 light curves
table3.dat 46 394 The two-color flux deviations from the seasonal
light curves
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See also:
J/AJ/110/1350 : Beta Lyrae light curve changes (Van Hamme+ 1995)
J/A+A/312/879 : Beta Lyr radial velocities and UBV data (Harmanec+, 1996)
J/A+A/463/233 : UBV and radial velocity light curves of beta Lyr (Ak+, 2007)
J/ApJ/750/59 : BVR polarimetric observations of β Lyr (Lomax+, 2012)
J/A+A/618/A112 : β Lyr light curves (Mourard+, 2018)
J/AJ/156/12 : Photometry of β Lyrae by the BRITE satellites
(Rucinski+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Sat [1/3] Satellite code (G1)
3- 11 F9.4 d t [2274.6697/2415.2058] Mean heliocentric time;
HJD-2456000
13- 18 F6.4 --- Phase [0.0008/0.9994] Binary orbital phase (G2)
20- 25 F6.4 mag magmean [3.2759/4.4093] Mean magnitude (G3)
27- 32 F6.4 mag e_magmean [0.0006/0.007] Error in magmean (1)
34- 35 I2 --- N [7/45] Number of averaged observations (2)
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Note (1): From the scatter of individual N observations.
Note (2): The data consist of the satellite setups partitioned at:
BTr: t = 2286.6, 2304.6, 2371.6;
BHr: t = 2325.6;
BLb: t = 2354.9.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 1 I1 --- Sat [1/3] Satellite code (G1)
3- 8 F6.4 --- Phase [0.0041/0.9956] Average orbital phase (1)
10- 15 F6.4 mag magmean [3.3005/4.3628] Mean magnitude (G3)
17- 22 F6.4 mag e_magmean [0.0004/0.0213] Error in magmean (2)
24- 25 I2 --- N [2/16] Number of averaged observations
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Note (1): Of the binary in intervals of 0.01 in phase. The phases are calculated
using the locally linear elements based on the quadratic ephemeris by
Ak et al. (2007A&A...464..233A 2007A&A...464..233A) for t=HJD-2456000, E=3875: t0=2347.0119 and
P0=12.94379 d.
Note (2): From the scatter of points in phase interval of 0.01.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 F9.4 d t [2349.1575/2385.8701] Mean heliocentric time;
HJD-2456000
11- 16 F6.4 --- Phase [0.0021/0.9967] Orbital phase (G2)
18- 24 F7.4 --- delR [-0.04/0.0364] Red color deviation (1)
26- 31 F6.4 --- e_delR [0.0029/0.0119] Estimated uncertainty in delR
33- 39 F7.4 --- delB [-0.0226/0.0268] Blue color deviation (2)
41- 46 F6.4 --- e_delB [0.0032/0.012] Estimated uncertainty in delB
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Note (1): Of the observed value of the flux from the seasonal light curve as
observed by the BTr satellite. The fluxes have been normalized to unity at the
maximum brightness of the binary system m0=3.30 for the BTr satellite.
Note (2): Of the observed value of the flux from the seasonal light curve as
observed by the BLb satellite. The fluxes have been normalized to unity at the
maximum brightness of the binary system m0=3.515 for the BLb satellite.
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Global notes:
Note (G1): Satellite code as follows:
1 = Red-filter satellite BRITE-Toronto (BTr);
2 = Red-filter satellite BRITE-Heweliusz (BHr);
3 = Blue-filter satellite BRITE-Lem (BLb).
Note (G2): Calculated using the locally linear elements based on the quadratic
ephemeris by Ak et al. (2007A&A...464..233A 2007A&A...464..233A) for E=3875, t0=2347.0119 and
P0=12.94379 d.
Note (G3): With an arbitrary zero point from the BRITE pipeline processing.
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History:
From electronic version of the journal
References:
Rucinski et al. Paper I. 2018AJ....156...12R 2018AJ....156...12R, Cat. J/AJ/156/12
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 31-Oct-2019