J/MNRAS/434/38 25-years photometry of V1057 Cygni (Kopatskaya+, 2013)
Photometric behaviour of the FU Orionis type star, V1057 Cygni, during the
last 25 years.
Kopatskaya E.N., Kolotilov E.A., Arkharov A.A.
<Mon. Not. R. Astron. Soc., 434, 38-45 (2013)>
=2013MNRAS.434...38K 2013MNRAS.434...38K
ADC_Keywords: Stars, variable ; Photometry, UBVRIJKLMNH
Keywords: stars: individual: V1057 Cyg - stars: pre-main sequence -
stars: variables: general
Abstract:
The FU Orionis type of variable star (FUor), V1057 Cygni, underwent a
nova-like outburst in 1969-1970. Among the FUors, V1057 Cyg is notable
for having the most dramatic post-maximum decrease in brightness.
Thus, photometric monitoring of this object is important for
interpretations of the cause of this event. Here, we study the
behaviour of V1057 Cyg over the last 25 years on the basis of our
optical and infrared observations. The optical and near-infrared
observations of V1057 Cyg started in 1974, and we present all our data
(up to the end of 2011), including 1085 and 167 nights of optical and
infrared photometry, respectively. The UBVRIJHKLM light curves
for 1985-2011 show that despite the increased photometric activity,
after a rapid decrease in brightness in the mid-1990s, the average
level of brightness remained practically constant. After the object
becomes fainter than V∼11.5mag, a swerve appears in the track of the
colour-magnitude diagram. The light variability shows a different
periodicity in different spectral regions. We have discovered a period
of 1631±60d in the BVR bands (1995-2011) and 523±40d in the RIJHK
bands (2002-2011) with amplitudes of 0.5-0.3mag. The 523-d period is
presumably correlated with the changes in the radial velocity of an
emission component in LiI. We conclude that the observed properties of
the FUor star V1057 Cyg are in accordance with current models of FUors
involving binary or multiple systems.
Description:
For table3, light curve has been constructed on our observations and on the
published data from 24 papers:
1: Alksnis A., 1971, Astron. Circ. (Russia), 635, 5
2: Bossen H., 1972, IBVR, 722
3: Filin A. Y., 1974, Peremennye zvezdy Suppl. (Russia), 2, 63
4: Gieseking P., 1973, IBVS, 806, 3
5: Gieseking P., 1974, AA, 31, 117
6: Haro G., 1972, IBVR, 714
7: Herbst W., Herbst D., Grossman E. J., 1994, AJ, 108, 1906
8: Hopp U., Kiehl M., Witsigmann S., 1979, IBVS, 1637
9: Kiselev N. N., 1972, Astron. Circ. (Russia), 742, 7
10: Landolt A. U., 1975, PASP, 87, 379
11: Landolt A. U., 1977, PASP, 89, 704
12: Mandel O. E., 1971, Astron. Circ. (Russia), 637, 5
13: Mandel O. E., 1975, Peremennye zvezdy, 20, 123
14: Mandel O. E., 1975, IAU Symp. 67, 123
15: Meinunger L., Wenzel, W., 1971, Mitt. Veranderl. Sterne, 5, 170
16: Mendoza V. E. E., 1971, ApJ(L), 169, L117
17: Oskanyan A., private communication
18: Rieke G., Lee T., Coyne G, 1972, PASP, 84, 37
19: Schwartz R. D., Snow T. P., 1972, ApJ(L), 177, L85
20: Simon T., Morrison N. D., Wolff S. C., Morrison D., 1972, AA, 20, 99
21: Tsvetkov M. K., 1976, IBVS, 1120
22: Welin G., 1975, IBVS, 1057
23: Welin G., 1976, IBVS, 1195
24: Wenzel, W. : 1963, Mitt. Veranderl. Sterne, 730.
Necessary reductions of the data have been executed.
Objects:
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RA (2000) DE Designation(s)
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20 58 53.72 +44 15 28.3 V1057 Cyg = HBC 300
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 65 1085 Optical photometry of V1057 Cyg in 1974-2011
table2.dat 38 173 JHKLM photometry of V1057 Cyg in 1984-2011
table3.dat 15 1178 Collective V-band light curve from pre-outburst
up to 1990 year
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See also:
J/AZh/88/34 : Long-term (1984-2008) JHKLM photometry of stars (Shenavrin+ 2011)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 d JD Julian date (JD-2400000)
12- 16 F5.2 mag Umag ?=- Johnson U magnitude
17 A1 --- u_Umag Uncertainty flag on Umag
19- 24 F6.3 mag Bmag ?=- Johnson B magnitude
25 A1 --- u_Bmag Uncertainty flag on Bmag
28- 33 F6.3 mag Vmag ?=- Johnson V magnitude
34 A1 --- u_Vmag Uncertainty flag on Vmag
35- 40 F6.3 mag Rcmag ?=- Cousins R magnitude
42- 47 F6.3 mag Icmag ?=- Cousins I magnitude
49- 54 F6.3 mag Rjmag ?=- Johnson R magnitude
56- 61 F6.3 mag Ijmag ?=- Johnson I magnitude
63- 65 A3 --- Obs Observer name (1)
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Note (1): Observers are:
kop = Kopatskaya.
* Before JD2447836 UBVR monitoring was performed with the use
of the 48-cm reflector of the Byurakan Station (Armenia) of the
Astronomical Observatory of the Leningrad (now St. Petersburg)
State University.
Errors are 0.01-0.02 mag in VR-bands, 0.02-0.03 in B and 0.03-0.04 in U.
* Observations in JD2452075-2452249 were performed in Nauchny (Ukraine)
by Shakhovskoi (Kopatskaya et al., 2002, Astrophysics, 45, 143).
* Further the photometry in the UBVRcIc bands was performed using the
70-cm AZT-8 telescope of the Crimean Astrophysical Observatory
(Nauchny, Ukraine) and the LX200 telescope in Petrodvorets
(St. Petersburg) with the use of the CCD-camera ST-7XME.
Errors are 0.002-0.003 mag in VRI, 0.01 in B, 0.05-0.06 in U.
RI-Cousins photometry was transformed to the Johnson system using the
formulae given by Fernie J.D. (1983PASP...95..782F 1983PASP...95..782F) for very red stars.
kol = Kolotilov.
UBV photometry was started in 1976 with the use of the 60-cm and
125-cm telescopes of the Crimean Laboratory (Nauchny, Ukraine) of
the Sternberg Astronomical Institute of the Moscow State University
(Kolotilov E.A., 1990PAZh...16...24K 1990PAZh...16...24K).
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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- 10 F10.4 d JD Julian date (JD-2400000)
12- 15 F4.2 mag Jmag ?=- Johnson J magnitude
17- 20 F4.2 mag Hmag ?=- Johnson H magnitude
22- 25 F4.2 mag Kmag ?=- Johnson K magnitude
27- 30 F4.2 mag Lmag ?=- Johnson L magnitude
32- 35 F4.2 mag Mmag ?=- Johnson M magnitude
37- 38 A2 --- Obs Observer name (1)
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Note (1): Observer as follows:
Sh = Shenavrin. JHKLM photometry was performed with use of the 125-cm
telescopes of the Crimean Laboratory (Nauchny, Ukraine) of the
Sternberg Astronomical Institute of the Moscow State University
(Shenavrin V.I., Taranova O.G., Nadjip A.E., 2011ARep...55...31S 2011ARep...55...31S,
Cat. J/AZh/88/34)
Ar = Arkharov. The infrared JHK-photometry was performed with the use of the
AZT-24 telescope of the Pulkovo Observatory installed at the Campo
Imperatory (Italy). Errors is 0.001 mag in JHK.
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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 F9.3 d JD Julian date (JD-2400000)
11- 15 F5.2 mag Vmag V magnitude
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Jul-2014