J/A+A/509/A17 R light curves of NGC 6253 variables (De Marchi+, 2010)
The first search for variable stars in the open cluster NGC 6253 and its
surrounding field.
De Marchi F., Poretti E., Montalto M., Desidera S., Piotto G.
<Astron. Astrophys. 509, A17 (2010)>
=2010A&A...509A..17D 2010A&A...509A..17D
ADC_Keywords: Clusters, open ; Stars, variable ; Photometry
Keywords: stars: starspots - stars: statistics - stars: variables: general -
binaries: eclipsing - novae, cataclysmic variables -
open clusters and associations: individual: NGC 6253
Abstract:
This work presents the first high-precision variability survey in the
field of the intermediate-age, metal-rich open cluster NGC 6253. We
discovered 595 variables and we also characterized most of them
providing their variability classes, periods and amplitudes. The
sample is complete at short periods: we classified 20 pulsating
variables, 225 contact systems, 99 eclipsing systems (22 Beta Lyr
type, 59 Beta Per type, 18 RS CVn type), and 77 rotational variables.
The time-baseline hampered the precise characterization of 173
variables with periods longer than 4-5days. Moreover, we found a
cataclysmic system undergoing an outburst of about 2.5mag.
Description:
The 595 files are listed in the file stars.list, together with the
number of individual measurements. Each file xxxxx_y.dat contains the
R timeseries of the variable xxxxx_y. The xxxxx number indicates the
identifier of the variable, the y number the WFI chip it is belonging
to.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 124 595 All the variables discovered in our survey of
NGC 6253 and its surrounding field
(tables A1-A8 of the paper)
tablea9.dat 112 22 List of binary systems (contact, detached and
semi-detached binaries) located at less than 8'
from the centre which are considered as candidate
members of NGC 6253
tablea10.dat 107 33 List of rotational and long-period variables
located at less than 8' from the centre which
are considered to be candidate cluster members
lc/* . 595 Individual light curves
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See also:
J/A+A/505/1129 : BVRIJHK and proper motions in NGC 6253 (Montalto+, 2009)
Byte-by-byte Description of file: stars.dat tablea10.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Tab Table number for type of variable (1)
4- 8 I5 --- Star [114/30482] Star sequential number
9 A1 --- --- [_]
10 I1 --- Chip [1/8] WFI chip number
12- 17 I6 --- [MPD2009] ?=- Montalto et al., 2009, Cat. J/A+A/505/1129
catalog identification number
19- 24 A6 --- VType Variable type (G1)
26- 38 F13.9 deg RAdeg Right ascension in decimal degrees (J2000)
40- 52 F13.9 deg DEdeg Declination in decimal degrees (J2000)
54- 59 F6.3 mag <Rmag> Mean R magnitude
61- 66 F6.3 mag <Vmag> ?=- Mean V magnitude
68- 72 F5.3 mag <B-V> ?=- Mean B-V colour index
74- 78 F5.3 mag <V-I> ?=- Mean V-I colour index
80- 85 F6.3 d Tmax ?=- Epoch of maximum brightness, HJD-2453100
87- 93 F7.5 d Per ?=- Period
95- 98 F4.2 mag Ramp Amplitude of variation in R band
99 A1 --- u_Ramp Uncertainty flag on Ramp
101-104 F4.1 arcmin Dist Distance from cluster centre
106-107 I2 % MP ?=- Membership probability
108 A1 --- u_MP [*] Uncertainty flag (stars with V>18, often
close to the chip borders) on MP
110-112 I3 --- Nm ? Number of measurements
114-124 A11 --- FileName Name of the file containing the light curve
in the "lc" subdirectory.
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Note (1): Type of variable code as follows:
1 = Pulsating variables
2 = Contact binaries, W Ursae Majoris (EW) systems
3 = Detached systems, β Per (Algol) type (EA) systems
4 = Semi-detached systems, β Lyr type (EB) systems
5 = RS CVn variables, binary systems showing stellar activity
in one or both components
6 = Single-wave rotational variables (RO1)
7 = Double-wave rotational variables (RO2)
8 = Long-period variables
10 = Rotational and long-period variables
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Byte-by-byte Description of file: tablea9.dat
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Bytes Format Units Label Explanations
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1 A1 --- Code [cd] contact or (semi-)detached binary
3- 7 I5 --- Star [114/30482] Star sequential number
8 A1 --- --- [_]
9 I1 --- Chip [1/8] WFI chip number
11- 16 I6 --- [MPD2009] ?=- Montalto et al., 2009, Cat. J/A+A/505/1129
catalog identification number
18- 23 A6 --- VType Variable type (G1)
25- 37 F13.9 deg RAdeg Right ascension in decimal degrees (J2000)
39- 51 F13.9 deg DEdeg Declination in decimal degrees (J2000)
53- 58 F6.3 mag Rmax Maximum R magnitude
60- 65 F6.3 mag <Vmag> ?=- Mean V magnitude
67- 71 F5.3 mag <B-V> ?=- Mean B-V colour index
73- 77 F5.3 mag <V-I> ?=- Mean V-I colour index
79- 84 F6.3 d Tmin ?=- Epoch of minimum brightness, HJD-2453100
86- 92 F7.5 d Per ?=- Period
94- 97 F4.2 mag Ramp Amplitude of variation in R band
99-101 F3.1 arcmin Dist Distance from cluster centre
103-104 I2 % MP ?=- Membership probability
106 A1 --- MP1 [y/n] CMD B-V membership
108 A1 --- MP2 [y/n] CMD V-I membership
110 A1 --- MP3 [y/n] PLC B-V membership
112 A1 --- MP4 [y/n] PLC V-I membership
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Byte-by-byte Description of file: lc/*
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Bytes Format Units Label Explanations
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1- 15 F15.7 d HJD Heliocentric JD of the observation
20- 27 F8.4 mag Rmag R magnitude
31- 40 F10.5 mag e_Rmag ?=1000. Photometric error of the observation
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Global Notes:
Note (G1): the variability types are as follows:
BCEP = β Cep
DSCT = δ Sct
HADS = High-amplitude δ Sct
RR = RR Lyr
EA = Eclipsing binary (Algol type)
EB = Eclipsing binary (β Lyr type, semi-detached)
EW = Eclipsing binary (W Uma type, contact)
RS CVn = spotted stars in system
Erupt. = eruptive variable
LON = Long-period variable
RO1 = rotational variables showing a single-wave light curve
often asymmetrical.
RO2 = rotational variables showing a more complicated curve than RO1,
composed of two waves having unequal amlitude and duration.
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Acknowledgements:
Ennio Poretti, ennio.poretti(at)brera.inaf.it
History:
* 09-Oct-2009: First version, without star positions
* 05-Feb-2011: Added positions and M2009 identification in "stars.dat"
file, from author (Ennio Poretti)
* 19-Aug-2011: data of tables A1-A8 added in stars.dat file
(End) Ennio Poretti [INAF-OA Brera, Italy], Patricia Vannier [CDS] 09-Oct-2009