J/A+A/445/617 V823 Cas BV(RI)c differential photometry (Jurcsik+, 2006)
The triple-mode pulsating variable V823 Cas.
Jurcsik J., Szeidl B., Varadi M., Henden A., Hurta Zs., Lakatos B.,
Posztobanyi K., Klagyivik P., Sodor A.
<Astron. Astrophys. 445, 617 (2006)>
=2006A&A...445..617J 2006A&A...445..617J
ADC_Keywords: Stars, variable ; Photometry, CCD ; Photometry, UBVRI ;
Photometry, Cousins
Keywords: stars: individual: V823 Cas - stars: variables: Cepheids -
stars: oscillations - stars: evolution - techniques: photometric
Abstract:
Using extended multicolour CCD photometry of the triple-mode radial
pulsator V823 Cas we studied the properties of the coupling
frequencies invoked by nonlinear processes. Our results support that a
resonance connection affects the mode coupling behaviour. The P1/P0
period ratio of V823 Cas has an "out of range" value if compared with
the period ratios of the known double mode pulsators, while the P2/P1
period ratio is normal. The periods and period ratios cannot be
consistently interpreted without conflict with pulsation and/or
evolution models. We describe this failure with the suggestion that at
present, the periods of V823 Cas are in a transient, resonance
affected state, thus do not reflect the true parameters of the object.
The anomalous period change behaviour of the fundamental and second
overtone modes supports this idea. We have also raised the possibility
that a f0+f2=2f1 resonance may act in triple mode pulsators.
Description:
The observations were obtained with the automated 60cm telescope of
Konkoly Observatory, Svabhegy, Budapest equiped with a Wright 750x1100
CCD using BV(RI)c filters, between 25 September and 14 December in
2003.
Objects:
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RA (2000) DE Designation(s)
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00 05 42.4 +63 24 14 V823 Cas = V* V823 Cas
00 05 49.2 +63 23 20 GSC 04018-01777 = GSC 04018-01777
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 97 467 BVRI magnitudes of calibrating stars
table2.dat 20 3582 Relative B magnitude of V823 Cas respect to
GSC 04018-01777
table3.dat 44 3637 Relative V magnitude of V823 Cas respect to
GSC 04018-01777 and
B-V, V-Rc and V-Ic colour indices of V823 Cas
table4.dat 20 3633 Relative Rc magnitude of V823 Cas respect to
GSC 04018-01777
table5.dat 20 3530 Relative Ic magnitude of V823 Cas respect to
GSC 04018-01777
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See also:
J/A+A/430/1049 : R Gem BV(RI)c differential photometry (Jurcsik+, 2005)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.6 deg RAdeg Right ascension (epoch J2000.0)
11- 15 F5.3 arcsec e_RAdeg Error in RA*cos(DE)
18- 26 F9.6 deg DEdeg Declination (epoch J2000.0)
29- 33 F5.3 arcsec e_DEdeg Error of the declination
36 I1 --- Nobs [1/2] Number of observations
39- 44 F6.3 mag Vmag Johnson V magnitude
46- 51 F6.3 mag B-V Johnson B-V colour index
53- 58 F6.3 mag V-Rc ?=99.999 V-Rc colour index
60- 65 F6.3 mag Rc-Ic ?=99.999 Rc-Ic colour index
68- 73 F6.3 mag e_Vmag Error of the V magnitude
76- 81 F6.3 mag e_B-V Error of the B-V colour index
84- 89 F6.3 mag e_V-Rc ?=9.999 Error of the V-Rc colour index
92- 97 F6.3 mag e_Rc-Ic ?=9.999 Error of the Rc-Ic colour index
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Byte-by-byte Description of file: table2.dat table4.dat table5.dat
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Bytes Format Units Label Explanations
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1- 12 F12.4 d HJD Heliocentric Julian Date
15- 20 F6.3 mag Dmag Relative B, Rc or Ic magnitude,
V823 Cas - GSC 04018-01777
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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- 12 F12.4 d HJD Heliocentric Julian Date
15- 20 F6.3 mag DVmag Relative V magnitude, V823 Cas - GSC 04018-01777
23- 28 F6.3 mag B-V Johnson B-V colour index of V823 Cas
31- 36 F6.3 mag V-Rc V-Rc colour index of V823 Cas
39- 44 F6.3 mag V-Ic V-Ic colour index of V823 Cas
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Acknowledgements: A. Sodor, sodor(at)konkoly.hu
(End) Patricia Vannier [CDS] 15-Sep-2005