J/A+AS/131/321 Long-term monitoring of active stars. VIII. (Cutispoto 1998)
Long-term monitoring of active stars.
VIII. UBV(RI)c photometry collected in February 1992
Cutispoto G.
<Astron. Astrophys. Suppl. Ser. 131, 321 (1998)>
=1998A&AS..131..321C 1998A&AS..131..321C
ADC_Keywords: Stars, variable ; Photometry, UBVRI ; Photometry, Cousins ;
Stars, flare
Keywords: stars: activity - stars: flare - stars: late-type -
stars: variables - stars: population II - stars: pre-main sequence
Abstract:
As a part of an extensive program focusing on the global properties
and evolution of active stars, high-precision UBV(RI)c photometry of
31 selected stars, collected at the European Southern Observatory over
the 14-29 February 1992 interval, is presented. Significant evolution
of the light curves, period variations and evidence for long-term
variability of the global degree of spottedness are found. Some
spectral classifications are revised and the inferred photometric
parallaxes are compared, whenever possible, with the values measured
by the Hipparcos satellite. Flare events were detected for the star
HD 16157=CC Eri, EXO 055609-3804.4=TY Col and HD 119285=V851 Cen.
Optical variability was discovered for the Pop II binary HD 89499.
These observations contribute to the establishment of a time-extended
photometric database which can give important clues on topics such as
the stability of spotted areas, differential rotation, solar-like
cycles and the correlation between inhomogeneities at different
atmospheric levels.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 67 31 Comparison (c) and check (ck) stars for each
program star
table3.dat 37 58 V magnitude and colors for the c and ck stars
derived from standard stars.
table4.dat 103 31 Maximum luminosity and corresponding colors
measured for the program stars
ubvri.dat 63 418 UBV(RI)c data
tables.ps 72 1366 PostScript version of tables 1-4
tables.tex 80 269 LaTeX version of tables 1-4
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See also:
J/A+AS/119/281 : Long-term monitoring of active stars. V. (Cutispoto, 1996)
J/A+AS/121/369 : Long-term monitoring of active stars. VI. (Cutispoto, 1997)
J/A+AS/127/207 : Long-term monitoring of active stars. VII. (Cutispoto 1998)
J/A+A/400/659 : Long-term monitoring of active stars. X. (Cutispoto+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Star Program star
15- 24 A10 --- Name Other name of the program star
26- 35 A10 ---- Comp Comparison star name (c)
37- 45 A9 ---- Check Check star name (ck)
47- 49 I3 mmag e(v-c) Standard deviation for the v-c V-band differential
magnitude for each series of N nights
51 I1 mmag e(ck-c) Standard deviation for the ck-c V-band differential
magnitude for each series of N nights
53- 54 I2 --- N Number of nights
56- 58 F3.2 mag DeltaV Amplitude of the V-band light curve
60- 67 F8.5 d Per ? Period of variability
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Table 2: Mean atmospheric extinction coefficients for La Silla site,
obtained over the 14-29 February 1992 period
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U B V R I
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Mag/airmass .538 .308 .203 .165 .118
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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- 10 A10 --- Name Comparison or check star name
12- 15 F4.2 mag Vmag V magnitude
17- 20 F4.2 mag U-B U-B colour index
21 A1 --- u_U-B Uncertainty flag on U-B (1)
23- 26 F4.2 mag B-V B-V colour index
28- 31 F4.2 mag V-Rc V-Rc colour index
33- 36 F4.2 mag V-Ic V-Ic colour index
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Note (1): Errors are of the order of 0.01 magnitudes. The symbol ":" denotes
errors of the order of 0.02 magnitudes
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Star Program star
15- 24 A10 --- Name Other name
26- 30 F5.2 mag Vmag V magnitude
32- 35 F4.2 mag U-B U-B colour index
37- 40 F4.2 mag B-V B-V colour index
42- 45 F4.2 mag V-Rc V-Rc colour index
47- 50 F4.2 mag V-Ic V-Ic colour index
52- 72 A21 --- SpType Spectral Type
74- 75 A2 --- l_DistH [≥ ] Limit flag on DistH
76- 80 F5.1 kpc DistH ? Distance range measured by the
Hipparcos satellite
81 A1 --- n_DistH [-] Dash when interval
82- 86 F5.1 kpc DistH2 ? Upper limit when interval
88- 89 A2 --- l_Distph [≥ ] Limit flag on Distph
90- 94 F5.1 kpc Distph Photometric distance inferred from the
adopted spectral classification
95 A1 --- n_Distph [-] Dash when interval
96- 98 I3 kpc Distph2 ? Upper limit when interval
100-104 F5.2 mag Vmax V-band maximum luminosity ever observed
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Byte-by-byte Description of file: ubvri.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Star name
11 A1 --- Note [fm] f: flare,
m: Manfroid et al. 1995, Cat. II/200
13- 24 F12.4 d HJD Heliocentric Julian date
26- 31 F6.5 --- Phase ? [0/1[ Phase (1)
32- 37 F6.3 mag Vmag V magnitude
39- 44 F6.3 mag U-B ? U-B colour index
46- 50 F5.3 mag B-V ? B-V colour index
52- 56 F5.3 mag V-R ? V-R colour index
58- 62 F5.3 mag V-I ? V-I colour index
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Note (1): Phases are computed by using the following ephemerides:
CC Eri (14-24 Feb 1992) HJD=2447129.52934 + 1.56145 X E
UX For (14-28 Feb 1992) HJD=2448660.0 + 0.957 x E
AG Dor (14-25 Feb 1992) HJD=2448666.0 + 2.533 x E
YY Men (14-29 feb 1992) HJD=2448660.0 + 9.75 x E
EZ Eri (14-28 Feb 1992) HJD=2448660.0 + 9.08 x E
YZ Men (14-29 Feb 1992) HJD=2448666.5 + 19.31 x E
UX Col (14-28 Feb 1992) HJD=2448660.0 + 2.29 x E
AB Dor (15-28 Feb 1992) HJD=2444296.575 + 0.51479 x E
V1321 Ori (14-28 Feb 1992) HJD=2448660.0 + 5.6 x E
SZ Pic (14-29 feb 1992) HJD=2443931.54 + 4.905 x E
TY Col (14-29 Feb 1992) HJD=2448660.0 + 3.62 x E
V344 Pup (14-25 Feb 1992) HJD=2448331.5 + 11.761
IL Hya (14-28 Feb 1992) HJD=2441466.213 + 12.86833 x E
LQ Hya (15-29 Feb 1992) HJD=2448660.0 + 1.61 x E
LZ Vel (14-29 Feb 1992) HJD=2448660.0 + 44.57 x E
HD 89499 (14-29 Feb 1992) HJD=2448660.0 + 5.574
SZ Crt (14-25 Feb 1992) HJD=2441389.0 + 11.58 x E
V858 Cen (14-29 Feb 1992) HJD=2448666.324 + 1.04303 x E
V829 Cen (14-29 Feb 1992) HJD=2448331.5 + 11.65 x E
V838 Cen (14-29 Feb 1992) HJD=2448660.0 + 1.848 x E
HU Vir (14-29 Feb 1992) HJD=2448331.5 + 10.424 x E
IN Vir (14-29 Feb 1992) HJD=2448660.0 + 8.4 x E
V851 Cen (14-26 Feb 1992) HJD=2448660.0 + 12.05 x E
V841 Cen (14-29 Feb 1992) HJD=2448660.0 + 5.929 x E
GX Lib (14-27 Feb 1992) HJD=2444678.4 + 11.134
V343 Nor (14-29 Feb 1992) HJD=2448660.0 + 4.32 x E
V991 Sco (16-27 Feb 1992) HJD=2448660.0 + 3.27 x E
V824 Ara (15-27 Feb 1992) HJD=2448660.0 + 1.71 x E
For the constant stars or those stars for which the period is not known
(HD 293857, SAO 121177 and HD 158394) there are only six columns in
the data tables, the phases column being not reported.
HD 293857 (14-27 Feb 1992)
SAO 121177 (13-14 Feb 1992)
HD 158394 (14-26 Feb 1992)
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Acknowledgements: Giuseppe Cutispoto
References:
Rodono & Cutispoto, Paper I. 1992A&AS...95...55R 1992A&AS...95...55R
Cutispoto, Paper II. 1992A&AS...95..397C 1992A&AS...95..397C
Cutispoto, Paper III. 1993A&AS..102..655C 1993A&AS..102..655C
Cutispoto, Paper IV. 1995A&AS..111..507C 1995A&AS..111..507C
Cutispoto, Paper V. 1996A&AS..119..281C 1996A&AS..119..281C, Cat. J/A+AS/119/281
Cutispoto, Paper VI. 1997A&AS..121..369C 1997A&AS..121..369C, Cat. J/A+AS/121/369
Cutispoto, Paper VII. 1998A&AS..127..207C 1998A&AS..127..207C, Cat. J/A+AS/127/207
Cutispoto et al., Paper IX 2001A&A...367..910C 2001A&A...367..910C, Cat. J/A+A/367/910
Cutispoto et al., Paper X 2003A&A...400..659C 2003A&A...400..659C, Cat. J/A+A/400/659
(End) Patricia Bauer [CDS] 28-May-1998