J/A+A/657/A123 OGLE IV and Gaia EDR3 data for RR Lyrae stars (Oliveira+, 2022)
Precise distances from OGLE-IV member RR Lyrae stars in six bulge globular
clusters.
Oliveira R.A.P., Ortolani S., Barbuy B., Kerber L.O., Maia F.F.S.,
Bica E., Cassisi S., Souza S.O., Perez-Villegas A.
<Astron. Astrophys. 657, A123 (2022)>
=2022A&A...657A.123O 2022A&A...657A.123O (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Stars, variable ; Combined data ; Optical
Keywords: stars: variables: RR Lyrae - globular clusters: general -
Galaxy: bulge
Abstract:
RR Lyrae stars are useful standard candles allowing one to derive
accurate distances for old star clusters. Based on the recent
catalogues from OGLE-IV and Gaia Early Data Release 3 (EDR3), the
distances can be improved for a few bulge globular clusters.
The aim of this work is to derive an accurate distance for the
following six moderately metal-poor, relatively high-reddening bulge
globular clusters: NGC 6266, NGC 6441, NGC 6626, NGC 6638, NGC 6642,
and NGC 6717.
We combined newly available OGLE-IV catalogues of variable stars
containing mean I magnitudes, with Clement's previous catalogues
containing mean V magnitudes, and with precise proper motions from
Gaia EDR3. Astrometric membership probabilities were computed for each
RR Lyrae, in order to select those compatible with the cluster proper
motions. Applying luminosity-metallicity relations derived from
BaSTI alpha-enhanced models (He-enhanced for NGC 6441 and canonical He
for the other clusters), we updated the distances with relatively low
uncertainties.
Distances were derived with the I and V bands, with a 5-8% precision.
We obtained 6.6kpc, 13.1kpc, 5.6 kpc, 9.6kpc, 8.2kpc, and 7.3kpc for
NGC 6266, NGC 6441, NGC 6626, NGC 6638, NGC 6642, and NGC 6717,
respectively. The results are in excellent agreement with the
literature for all sample clusters, considering the uncertainties.
The present method of distance derivation, based on recent data of
member RR Lyrae stars, updated BaSTI models, and robust statistical
methods, proved to be consistent. A larger sample of clusters will be
investigated in a future work.
Description:
In this paper, we combined OGLE-IV (Soszynski et al.,
2019AcA....69..321S 2019AcA....69..321S), Clement (Clement et al., 2001AJ....122.2587C 2001AJ....122.2587C,
Cat. V/150) and Gaia EDR3 (Gaia Collaboration 2021) catalogues for RR
Lyrae in six bulge globular clusters, in order to compute membership
probabilities and derive precise distances from member RR Lyrae. The
RR Lyrae combined catalogues for each of the clusters with the
membership values are provided here. The name of the columns from
OGLE-IV start with a 'ogle_', from Clement start with a 'clem_', and
from Gaia EDR3 start with a 'gaia_'. We also provide the suggested
corrections and catalogue validation from Gaia EDR3, and our computed
membership in the final columns.
Objects:
-----------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------
17 01 12.60 -30 06 44.5 NGC 6266
17 50 13.06 -37 03 05.2 NGC 6441
18 24 32.89 -24 52 11.4 NGC 6626
18 30 56.25 -25 29 47.1 NGC 6638
18 31 54.23 -23 28 34.1 NGC 6642
18 55 06.04 -22 42 05.3 NGC 6717
-----------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
ngc6266.dat 256 123 Combined catalogue and membership of
the RR Lyrae in NGC 6266
ngc6441.dat 256 37 Combined catalogue and membership of
the RR Lyrae in NGC 6441
ngc6626.dat 256 20 Combined catalogue and membership of
the RR Lyrae in NGC 6626
ngc6638.dat 256 28 Combined catalogue and membership of
the RR Lyrae in NGC 6638
ngc6642.dat 256 21 Combined catalogue and membership of
the RR Lyrae in NGC 6642
ngc6717.dat 256 3 Combined catalogue and membership of
the RR Lyrae in NGC 6717
--------------------------------------------------------------------------------
See also:
V/150 : Updated catalog of variable stars in globular clusters (Clement+ 2017)
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
Byte-by-byte Description of file: ngc*.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 20 A20 --- OGLE OGLE source identifier,
OGLE-BLG-RRLYR-NNNNN (ogle_id)
22- 31 F10.6 deg RAdeg Right Ascension (J2000) from OGLE-IV
(ogle_ra)
33- 42 F10.6 deg DEdeg Declination (J2000) from OGLE-IV (ogle_dec)
44- 49 F6.3 mag ImagO ?=- I mean magnitude from OGLE-IV (ogle_imag)
51- 58 F8.6 d PerO ?=- Period from OGLE-IV (light-curves in the
I band) (ogle_period)
60- 71 E12.6 d e_PerO ?=- Uncertainty of the period from OGLE-IV
(ogleuncperiod)
73- 77 F5.3 mag IAmpO ?=- Amplitude in the I band from OGLE-IV
(ogle_ampl)
79- 82 A4 --- TypeO Variable star type from OGLE-IV
(RRab, RRc, RRd) (ogle_type)
84- 87 A4 --- Clem ?=- Identifier in the Clement catalogue,
VNNN within the cluster (clem_id)
89- 94 F6.3 mag magC ?=- Mean magnitude from Clement
(in clem_filter) (clem_mag)
96-100 F5.3 mag AmpC ?=- Amplitude from Clement (in clem_filter)
(clem_ampl)
102 A1 --- FiltC [BVIP] Filter for magC and AmpC
(clem_filt) (1)
104-107 A4 --- TypeC Variable star type from Clement (RR0, RR1)
(clem_type)
109-127 I19 --- GaiaEDR3 Gaia EDR3 unique source identifier
(gaiasourceid)
129-138 F10.4 mas PlxG Parallax (gaia_parallax)
140-145 F6.4 mas e_PlxG Standard error of parallax
(gaiaparallaxerror)
147-155 F9.3 mas/yr pmRAG Proper motion in right ascension direction,
pmRA*cosDE (gaia_pmra)
157-161 F5.3 mas/yr e_pmRAG Standard error of proper motion in right
ascension direction (gaiapmraerror)
163-171 F9.3 mas/yr pmDEG Proper motion in declination direction
(gaia_pmdec)
173-177 F5.3 mas/yr e_pmDEG Standard error of proper motion in
declination direction (gaiapmdecerror)
179-187 F9.6 mag Gmag G-band mean magnitude (gaiaphotgmeanmag)
189-196 F8.6 mag BP-RP BP-RP colour (gaiabprp)
198-206 F9.6 --- E(BP/RP) Corrected BP/RP flux excess factor
(Riello et al., 2021A&A...649A...3R 2021A&A...649A...3R)
(gaiacorrphotbprpexcessfactor)
208-217 F10.4 mas PlxcorrG Corrected parallax (Lindegren et al.,
2021A&A...649A...4L 2021A&A...649A...4L) (gaiacorrparallax)
219-227 F9.3 mas/yr pmRAcorrG Corrected PM-RA bias (Cantat-Gaudin & Brandt,
2021A&A...649A.124C 2021A&A...649A.124C) (gaiacorrpmra)
229-237 F9.3 mas/yr pmDEcorrG Corrected PM-DE bias (Cantat-Gaudin & Brandt,
2021A&A...649A.124C 2021A&A...649A.124C) (gaiacorrpmdec)
239-245 F7.4 mag Gmagcorr Corrected gmag (Riello et al.,
2021A&A...649A...3R 2021A&A...649A...3R)
(gaiacorrphotgmean_mag)
247 I1 --- FlagsG [0/1] Combination of all flags
(1: good, 0: bad) (gaiaallflags)
249-256 F8.6 --- Memb Computed membership probability (Membership)
--------------------------------------------------------------------------------
Note (1): Filters as follows:
P = photographic
B = B band
V = V band
I - I band
--------------------------------------------------------------------------------
Acknowledgements:
Raphael A.P. Oliveira. rap.oliveira(at)usp.br
(End) Patricia Vannier [CDS] 26-Dec-2021