J/MNRAS/465/2489 NGC 6401 bulge variable stars (Tsapras+, 2017)
Variable stars in the bulge globular cluster NGC 6401.
Tsapras Y., Arellano Ferro A., Bramich D.M., Figuera Jaimes R., Kains N.,
Street R., Hundertmark M., Horne K., Dominik M., Snodgrass C.
<Mon. Not. R. Astron. Soc. 465, 2489 (2017)>
=2017MNRAS.465.2489T 2017MNRAS.465.2489T (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Stars, variable ; Photometry, SDSS
Keywords: stars: variables: RR Lyrae - globular clusters: individual: NGC 6401
Abstract:
We present a study of variable stars in globular cluster NGC 6401. The
cluster is only 5.3° away from the Galactic Centre and suffers
from strong differential reddening. The photometric precision afforded
us by difference image analysis resulted in improved sensitivity to
variability in formerly inaccessible interior regions of the cluster.
We find 23 RRab and 11 RRc stars within one cluster radius
(2.4-arcmin), for which we provide coordinates, finder-charts and time
series photometry. Through Fourier decomposition of the RR Lyrae star
light curves we derive a mean metallicity of [Fe/H]UVES=-1.13±0.06
([Fe/H]ZW=-1.25±0.06), and a distance of d∼6.35±0.81kpc. Using
the RR Lyrae population, we also determine that NGC 6401 is an
Oosterhoff type I cluster.
Description:
Observations of the target field were a by-product of the RoboNet
microlensing campaign and were obtained in the campaign-specific
SDSS-g' and SDSS-i' bands throughout the months of 2013 July and
August using the LCOGT1 1-m robotic telescope network. LCOGT
telescopes are clones of each other, featuring identical instruments,
and are deployed in clusters of two to three at the Siding Spring
Observatory (SSO), South African Astronomical Observatory (SAAO) and
Cerro Tololo Inter-American Observatory (CTIO).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table34.dat 122 70 Cluster variables (34 stars, table3) and
non-member variables (36 stars, table4)
table2.dat 94 56691 Time-series SDSS-g' and SDSS-i' photometry,
linearly transformed to the V and I bands,
respectively, for all of the confirmed
variables in our field of view
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See also:
J/MNRAS/372/69 : VR light curves of M2 variables (Lazaro+, 2006)
J/MNRAS/377/741 : VIc photometry of NGC 2516 (Irwin+, 2007)
J/MNRAS/384/1444 : Vr light curves of NGC 5466 RR Lyrae (Arellano Ferro+, 2008
J/MNRAS/402/226 : NGC 5053 variables VrI light curves (Arellano Ferro+, 2010)
J/MNRAS/413/1275 : VrI light curves of NGC6981 variables (Bramich+, 2011)
J/MNRAS/416/2265 : Variable stars in NGC 5024 (M53) (Arellano Ferro+, 2011)
J/MNRAS/420/1333 : NGC 5024 (M53) RR Lyrae VI light curves
(Arellano Ferro+, 2012)
J/MNRAS/424/2722 : Variable stars in NGC 5024 (M53) (Bramich+, 2012)
J/A+A/548/A92 : VrI light curves of NGC1904 variables (Kains+, 2012)
J/MNRAS/434/1220 : Vi light curves of NGC6333 variables (Arellano Ferro+, 2013
J/A+A/555/A36 : VrI light curves of NGC7099 variables (Kains+, 2013)
J/A+A/556/A20 : Variable stars in globular NGC7492 (Figuera Jaimes+, 2013)
J/MNRAS/452/727 : NGC 6229 variable VI light curves (Arellano Ferro+, 2015)
J/A+A/573/A103 : Light curves for variables in 5 clusters (Skottfelt+, 2015)
J/A+A/578/A128 : VI light curves of NGC4590 variables (Kains+, 2015)
J/A+A/588/A128 : Variable stars in globular clusters (Figuera Jaimes+, 2016)
J/A+A/592/A120 : Variable stars in NGC 6715 (Figuera Jaimes+, 2016)
J/other/ApSS/361.175 : M5 RR Lyr and HB VI light curves (Arellano Ferro+, 2016)
Byte-by-byte Description of file: table34.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Memb? [M nM] M for members, nM for non-members
4- 23 A20 --- VName Variable star ID, VNN or other
25- 44 A20 --- OGLE OGLE ID (OGLE-BLG-RRLYR-NNNNN)
46- 50 A5 --- VType Variable type
52- 58 F7.5 d Per ?=- Period
60- 66 F7.5 d PerO ?=- OGLE period
68- 69 I2 h RAh Right ascension (J2000)
71- 72 I2 min RAm Right ascension (J2000)
74- 78 F5.2 s RAs Right ascension (J2000)
80 A1 --- DE- Delcination sign (J2000)
81- 82 I2 deg DEd Delcination (J2000)
84- 85 I2 arcmin DEm Delcination (J2000)
87- 90 F4.1 arcsec DEs Delcination (J2000)
92- 96 F5.2 mag <Vmag> ?=- Mean V magnitude
98-102 F5.2 mag <Imag> ?=- Mean I magnitude
104-107 F4.2 mag Ag ?=- Amplitude in g band (for members only)
109-112 F4.2 mag Ai ?=- Amplitude in i band (for members only)
114-122 F9.4 d Epoch Epoch (HJD-2450000)
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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- 20 A20 --- VName Variable star Name
22 A1 --- Filt [gi] Filter
24- 36 F13.5 d HJD Heliocentric Julian Date
38- 43 F6.3 mag mag.s Standard magnitude in Filter
45- 50 F6.3 mag mag.i Instrumental magnitude in Filter
52- 56 F5.3 mag e_mag.i Magnitude uncertainty (standard or instrumental)
58- 65 F8.3 s-1 Fref Reference flux in Filter (in ADU/s unit)
67- 71 F5.3 s-1 e_Fref Reference flux uncertainty (in ADU/s unit)
73- 80 F8.3 s-1 DFlux Difference flux (in ADU/s unit)
82- 87 F6.3 s-1 e_DFlux Difference flux uncertainty (in ADU/s unit)
89- 94 F6.4 --- p Photometric scale factor
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Acknowledgements:
Daniel Bramich, dan.bramich(at)hotmail.co.uk
(End) Patricia Vannier [CDS] 06-Feb-2017