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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
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:
FileName Lrecl Records Explanations
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 124 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/* 40 595 Individual light curves
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
Bytes Format Units Label Explanations
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.
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
Byte-by-byte Description of file: tablea9.dat
Bytes Format Units Label Explanations
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
Byte-by-byte Description of file: lc/*
Bytes Format Units Label Explanations
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
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.
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
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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