J/ApJ/647/1375 BV light curves of γ Cas (Smith+, 2006)
Rotational and cyclical variability in γ Cassiopeia.
Smith M.A., Henry G.W., Vishniac E.
<Astrophys. J., 647, 1375-1386 (2006)>
=2006ApJ...647.1375S 2006ApJ...647.1375S
ADC_Keywords: Stars, Be ; Photometry, UBV
Keywords: stars: emission-line, Be-stars: individual (gamma Cassiopeia) -
X-rays: stars
Abstract:
Gamma Cas is an unusual classical Be star for which the optical-band
and hard X-ray fluxes vary on a variety of timescales. We report
results of a 9yr monitoring effort on this star with a robotic
ground-based (APT) telescope in the B, V filter system, as well as
simultaneous observations in 2004 November with this instrument and
the RXTE. Our observations disclosed no correlated optical response to
the rapid X-ray flares in this star, nor did the star show any
sustained flux changes any time during two monitored nights in either
wavelength regime. Consistent with an earlier study by Robinson et al.
(2002ApJ...575..435R 2002ApJ...575..435R), optical light curves obtained in our new APT
program revealed that Cas undergoes ∼3% amplitude cycles with lengths
of 50-91days. Our observations in 2004 showed a similar optical cycle.
Over the 9 days we monitored the star with the RXTE, the X-ray flux
varied in phase with its optical cycle and with an amplitude predicted
from the data in Robinson et al. (2002ApJ...575..435R 2002ApJ...575..435R).
Objects:
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RA (2000) DE Designation(s) (Star)
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00 56 42.5 +60 43 00 Gamma Cas = HR 264 (Variable)
00 56 39.9 +59 10 52 HD 5395 = * 28 Cas (Comp)
01 04 19.5 +61 34 49 HD 6210 = HR 297 (Check)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 40 3263 Photometric observations of γ Cas
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See also:
J/A+A/284/515 : Long-term periodic variability in gamma Cas (Telting+ 1994)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 F12.4 --- HJD Heliocentric Julian Date
14- 19 F6.3 mag VarB ?=99.999 Variable-Comparison (Gam Cas-HD 6210)
differential magnitude in B (1)(2)
21- 26 F6.3 mag VarV ?=99.999 Variable-Comparison (Gam Cas-HD 6210)
differential magnitude in V (1)(2)
28- 33 F6.3 mag ChkB ?=99.999 Check-Comparison (HD 5395-HD 6210)
differential magnitude in B (1)
35- 40 F6.3 mag ChkV ?=99.999 Check-Comparison (HD 5395-HD 6210)
differential magnitude in V (1)
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Note (1): The '99.999' signifies that the differential magnitude was discarded
because its internal standard deviation exceeded 0.01mag.
Note (2): To obtain mB, mV of HD110432, add 6.40, 5.84mag, respectively.
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History:
From electronic version of the journal
Reference:
Henry & Smith Paper II. 2012ApJ...760...10H 2012ApJ...760...10H Cat. J/ApJ/760/10
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 11-Jul-2008