J/AJ/116/1447 RZ Cas JK light curves (Varricatt+, 1998)
Near-infrared photometric studies of RZ Cassiopeiae.
Varricatt W.P., Ashok N.M., Chandrasekhar T.
<Astron. J. 116, 1447 (1998)>
=1998AJ....116.1447V 1998AJ....116.1447V (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Photometry, infrared
Keywords: binaries: eclipsing - stars: activity -
stars: individual (RZ Cassiopeiae) - stars: spots
Abstract:
Light curves of the Algol-type binary system, RZ Cassiopeiae, in the
near-IR wavelengths J and K are obtained for the first time. The light
curves are analyzed using the Wilson-Devinney model. UBV light curves
of RZ Cas obtained by Chambliss are also reanalyzed using the same
program. In the J and K bands, the bolometric albedo of the secondary
of RZ Cas exhibited values above 0.7, whereas the theoretically
expected value for such a star is 0.5. Also, the values of the
secondary temperature derived from the J and K light curves are found
to be less than that derived from our analysis of the optical light
curves as well as from the previous studies in the optical photometric
bands. We have attempted to model these effects with a dark spot on
the secondary of RZ Cas. The J-band light curve gave a better fit with
a cool dark spot on the secondary. Another possible reason for the
above mentioned effects is a gas stream from the lobe-filling
secondary to the primary star. The magnitudes and colors of the
individual components are derived from the observed light curves and
the light contributions from the stars derived from the light curve
analysis. The primary is found to be an A3 V star as observed by
previous investigators. The secondary is classified as K0K4 IV from
the derived colors. Seven epochs of primary minima and 3 epochs of
secondary minima are obtained from the observations. Because of the
increased depths of the secondary eclipse in the infrared bands, the
moments of minima are calculated with nearly the same accuracy as that
of the primary minima. All the secondary minima are found to occur at
phase 0.5. None of the observed primary minima are flat as found by
many observers before at optical wavelengths. The colors of the system
at the minima obtained by us confirm that the system is partially
eclipsing.
Objects:
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RA (2000) DE Designation(s)
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02 48 55.5 +69 38 03 RZ Cas = HD 17138
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 27 839 J-band light curve of RZ Cassiopeiae
tablea2.dat 27 947 K-band light curve of RZ Cassiopeiae
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Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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1- 13 F13.5 d HJD Heliocentric Julian date
15- 20 F6.4 --- Phase [0/1] Phase
22- 27 F6.3 mag Dmag Differential magnitude
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History: From AJ electronic version
(End) James Marcout, Patricia Bauer [CDS] 09-Mar-1999