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J/A+A/555/A36       VrI light curves of NGC7099 variables         (Kains+, 2013)

Estimating the parameters of globular cluster M 30 (NGC 7099) from time-series photometry. Kains N., Bramich D.M., Arellano Ferro A., Figuera Jaimes R., Jorgensen U.G., Giridhar S., Alsubai K.A., Andersen J.M., Bozza V., Browne P., Burgdorf M., Calchi Novati S., Damerdji Y., Diehl C., Dodds P., Dominik M., Elyiv A., Fang X.-S., Giannini E., Gu S.-H., Hardis S., Harpsoe K., Hinse T.C., Hornstrup A., Hundertmark M., Jessen-Hansen J., Juncher D., Kerins E., Kjeldsen H., Korhonen H., Liebig C., Lund M.N., Lundkvist M., Mancini L., Martin R., Mathiasen M., Penny M.T., Rabus M., Rahvar S., Ricci D., Sahu K., Scarpetta G., Skottfelt J., Snodgrass C., Southworth J., Surdej J., Tregloan-Reed J., Vilela C., Wertz O., Williams A. (The MiNDSTEp consortium) <Astron. Astrophys. 555, A36 (2013)> =2013A&A...555A..36K
ADC_Keywords: Clusters, globular ; Stars, variable ; Photometry, CCD Keywords: stars: variables: general - stars: variable: RR Lyrae - globular clusters: individual: NGC 7099 Abstract: We present the analysis of 26 nights of V and I time-series observations from 2011 and 2012 of the globular cluster M 30 (NGC 7099). We used our data to search for variable stars in this cluster and refine the periods of known variables; we then used our variable star light curves to derive values for the cluster's parameters. We used difference image analysis to reduce our data to obtain high-precision light curves of variable stars. We then estimated the cluster parameters by performing a Fourier decomposition of the light curves of RR Lyrae stars for which a good period estimate was possible. We also derive an estimate for the age of the cluster by fitting theoretical isochrones to our colour-magnitude diagram (CMD). Out of 13 stars previously catalogued as variables, we find that only 4 are bona fide variables. We detect two new RR Lyrae variables, and confirm two additional RR Lyrae candidates from the literature. We also detect four other new variables, including an eclipsing blue straggler system, and an SX Phoenicis star. This amounts to a total number of confirmed variable stars in M 30 of 12. We perform Fourier decomposition of the light curves of the RR Lyrae stars to derive cluster parameters using empirical relations. We find a cluster metallicity [Fe/H]ZW=-2.01±0.04, or [Fe/H]UVES=-2.11±0.06, and a distance of 8.32±0.20kpc (using RR0 variables), 8.10 kpc (using one RR1 variable), and 8.35±0.42kpc (using our SX Phoenicis star detection in M 30). Fitting isochrones to the CMD, we estimate an age of 13.0±1.0Gyr for M 30. Description: V and I time-series photometry and difference imaging parameters for all confirmed variables in NGC 7099. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file stars.dat 113 12 Data for all confirmed variable stars in NGC7099 (tables 3 and 5 of the paper) table2.dat 83 9654 V and I lightcurves
See also: J/other/MmSAI/20.63 : M30 V1-V3 variable light curves (Rosino, 1949) J/A+A/313/129 : M30 blue stars positions and magnitudes (Burgarella+ 1996) J/AJ/116/1757 : M30 UBV photometry (Guhathakurta+, 1998) J/ApJ/518/262 : CCD VIc Photometry of M30 stars (Sandquist+, 1999) J/ApJ/657/286 : Chandra X-ray sources in M30 (NGC 7099) (Lugger+, 2007) J/MNRAS/413/1275 : VrI light curves of NGC6981 variables (Bramich+, 2011) J/A+A/548/A92 : VrI light curves of NGC1904 variables (Kains+, 2012) Byte-by-byte Description of file: stars.dat
Bytes Format Units Label Explanations
1- 3 A3 --- VName Variable name, VNN, <Cl* NGC 7099 SAW VNN> in Simbad 4 A1 --- n_VName [bc] Individual notes on variables (1) 6- 7 I2 h RAh Right ascension (J2000) 9- 10 I2 min RAm Right ascension (J2000) 12- 16 F5.2 s RAs Right ascension (J2000) 18 A1 --- DE- Declination sign (J2000) 19- 20 I2 deg DEd Declination (J2000) 22- 23 I2 arcmin DEm Declination (J2000) 25- 28 F4.1 arcsec DEs Declination (J2000) 30- 38 F9.4 d Ep Epoch (HJD-2450000) 40- 48 F9.7 d Per Period 50- 58 F9.7 d Per1 ?=- Rosino (1949, J/other/MmSAI/20.63) period 59 A1 --- n_Per1 [a] Note on Per1 (2) 61- 65 F5.3 d Per2 ?=- Pietrukowicz et al. (2004AcA....54...19P) period (3) 67- 71 F5.2 mag <Vmag> Mean V magnitude (4) 73- 77 F5.2 mag <Imag> ? Mean I magnitude (4) 79 A1 --- l_Vamp [~] Limit flag on Vamp 80- 83 F4.2 mag Vamp Amplitude in V band 85- 88 F4.2 mag Iamp ?=- Amplitude in I band 90-113 A24 --- VType Variable type
Note (1): Notes on VName as follows: b = The period given for V4 is that of the sinusoidal variations seen during the quiescent part of the light curve, and the mean magnitudes are also those during quiescent phase; outburst mean magnitudes are given in the text c = For V19, the mean magnitudes are overestimated and amplitudes are underestimated due to blending, as discussed in the text Note (2): Note on Per1 as follows: a = Rosino (1961, Contr. Asiago-Padova, 117) revised the period of V1 to 0.743608d. Note (3): V15 = Cl* NGC 7099 PK 2 and V19 = Cl* NGC 7099 PK 3. Note (4): intensity-weighted mean magnitudes for RR Lyrae, inverse-variance-weighted mean magnitudes for other variables.
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 3 A3 --- VName Variable name, VNN 5 A1 --- Filter [VI] Observation filter 7- 19 F13.5 d HJD Heliocentric Julian date 21- 26 F6.3 mag mag.s Standard magnitude 28- 33 F6.3 mag mag.i Instrumental magnitude 35- 39 F5.3 mag e_mag.i Error on the magnitude 41- 49 F9.3 1/s Fref Reference flux (in ADU/s) 51- 56 F6.3 1/s e_Fref Error on the reference flux (in ADU/s) 58- 68 F11.3 1/s DFlux Differential flux (in ADU/s) 70- 76 F7.3 1/s e_DFlux Error on the differential flux (in ADU/s) 78- 83 F6.4 --- p Photometric scale factor
History: * 30-Dec-2013: On-line version * 15-Jul-2014: Units of Fref and DFlux corrected in 5*s-1 (instead of s-1), from author * 17-Jul-2014: Table2 corrected (units in s-1 with corresponding values), from author Acknowledgements: Noe Kains, nkains(at)
(End) Noe Kains [ESO], Patricia Vannier [CDS] 15-May-2013
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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