J/MNRAS/541/3146 NGC 5634 variable stars light curves (Arellano Ferro+, 2025)
The variable stars in the compact halo globular cluster NGC 5634 visited again.
Arellano Ferro A., Michel R., Yepez M.A., Muneer S., Bustos Fierro I.,
Prudil Z.
<Mon. Not. R. Astron. Soc. 541, 3146 (2025)>
=2025MNRAS.541.3146A 2025MNRAS.541.3146A (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Stars, variable ; Photometry, CCD ; Optical
Keywords: stars: horizontal branch - stars: variables: RR Lyrae -
Galaxy: fundamental parameters -
globular clusters: individual (NGC 5634)
Abstract:
We present new time-series CCD VR photometry of the globular cluster
NGC 5634. We aim to use the known RR Lyrae stars, members of the
cluster, as indicators of mean metallicity and distance. Accurate
coordinates, periods, and an identification chart of the variables in
the field of our images are provided. A membership analysis was
performed, based on Gaia-DR3 proper motions, for 3525 point sources
within 15 arcmin from the cluster centre. The membership status for
each known variable was established and it was found that V10, V11,
and V16 are most likely field stars. The variability of the RRab star
V7, considered non-variable for a number of years, is demonstrated.
Via the Fourier decomposition of the light curves of cluster member RR
Lyrae, the mean metallicity and distance were calculated independently
from RRab and RRc stars to find [Fe/H]ZW=-1.67±0.11 and
D=23.9±0.8kpc, and [Fe/H]ZW=-1.69±0.22 and D=22.9±1.0kpc,
respectively.
Description:
he data used in this work were obtained 1.5m telescope in San Pedro
Martir Observatory, Baja California, Mexico, between May 1 and May
11, 2024. Also the data were collected with the 2.0m telescope of the
Indian Astrophysical Observatory (IAO) at Hanle, India on March 3 and
April 4, 2024. The data reductions were carried out with the DanDIA
pipeline (Bramich 2008MNRAS.386L..77B 2008MNRAS.386L..77B; Bramich et al.
2013MNRAS.428.2275B 2013MNRAS.428.2275B).
A membership analysis was performed, based on Gaia-DR3 proper motions,
for 3525 point sources within 15 arcmin from the cluster center. An
updated census of the cluster member variables stars is discussed.
Cluster member RR Lyrae stars V light curves offered in this data base
were Fourier decomposed to find the mean metallicity and distance,
independently from RRab and RRc stars to find [Fe/H]ZW=-1.67±0.11
and D=23.9±0.8kpc, and [Fe/H]ZW=-1.69±0.22 and D=22.9±1.0kpc
respectively.
In the present data collection we offer our V and R photometry for V1,
V2, V3, V7, V13, V17, V18 and V19, and also include Gaia G, BP, RP
photometry transformed into V and I using the transformation equations
from Riello M., et al., 2021A&A...649A...3R 2021A&A...649A...3R (Cat. J/A+A/649/A3), for
stars V4, V5, V6 and V8.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 105 27 General data of the variables in the FoV of NGC 5634
table2.dat 50 7784 VR photometry for V1, V2, V3, V7, V13, V17, V18, V19
and VI photometry for V4, V5, V6 and V8 members
of NGC 5634
--------------------------------------------------------------------------------
See also:
J/ApJ/102/17 : V light curves of variable stars in NGC 6229 (Baade+, 1945)
J/AJ/124/915 : VI photometry of NGC 5634 (Bellazzini+, 2002)
J/A+A/579/A104 : Abundances in NGC 5053 and NGC 5634 (Sbordone+, 2015)
J/A+A/600/A118 : Abundances of red giant stars in NGC6093 (Carretta+, 2027)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- VName Variable name (V1-V21, G1-G6)
5- 23 I19 --- GaiaDR3 Gaia source number
25- 29 A5 --- Type Variable Type
30- 35 F6.3 mag <Vmag> ?=- Intensity weighted mean V magnitude
36 A1 --- u_<Vmag> Uncertainty flag on <Vmag>
38- 43 F6.3 mag <Rmag> ?=- Intensity weighted mean R magnitude
44 A1 --- u_<Rmag> Uncertainty flag on <Rmag>
46- 50 F5.3 mag AmpV ?=- V amplitude
52- 56 F5.3 mag AmpR ?=- R amplitude
57 A1 --- u_AmpR Uncertainty flag on AmpR
59- 66 F8.6 d Per ?=- Period
68- 76 F9.4 d Epoch ?=- Epoch of maximum (HJD-2460000)
78- 79 I2 h RAh Right Ascencion (J2000)
81- 82 I2 min RAm Right Ascencion (J2000)
84- 88 F5.2 s RAs Right Ascencion (J2000)
90 A1 --- DE- Declination sign (J2000)
91- 92 I2 deg DEd Declination (J2000)
94- 95 I2 arcmin DEm Declination (J2000)
97-101 F5.2 arcsec DEs Declination (J2000)
103 A1 --- Memb [m/f] Membership status
105 A1 --- lc [+] + indicates light curves data in table 2
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 4 A3 --- VName Variable name
10 A1 --- Filter [VRI] Observation filter (1)
15- 27 F13.5 d HJD Heliocentric Julian date
30- 35 F6.3 mag magstd Standard magnitude
38- 43 F6.3 mag maginst Instrumental magnitude
46- 50 F5.3 mag e_maginst Error on the magnitude
--------------------------------------------------------------------------------
Note (1): VR photometry for V1, V2, V3, V7, V13, V17, V18, V19 and
VI photometry for V4, V5, V6 and V8.
--------------------------------------------------------------------------------
Acknowledgements:
Armando Arellano Ferro, armando(at)astro.unam.mx
(End) A. Arelano Ferro [IA-UNAM, Mexico], P. Vannier [CDS] 08-Dec-2025