Article (Scientific journals)
Estimating the parameters of globular cluster M 30 (NGC 7099) from time-series photometry
Kains, N.; Bramich, D. M.; Arellano Ferro, A. et al.
2013In Astronomy and Astrophysics, 555, p. 36
Peer Reviewed verified by ORBi
 

Files


Full Text
ngc7099-2.pdf
Publisher postprint (4.26 MB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
stars: variables: general; stars: variables: RR Lyrae; globular clusters: individual: M 30 (NGC 7099)
Abstract :
[en] <BR /> Aims: 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. <BR /> Methods: 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 derived an estimate for the age of the cluster by fitting theoretical isochrones to our colour-magnitude diagram (CMD). <BR /> Results: 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][SUB]ZW[/SUB] = -2.01 ± 0.04, or [Fe/H][SUB]UVES[/SUB] = -2.11 ± 0.06, and a distance of 8.32 ± 0.20 kpc (using RR0 variables), 8.10 kpc (using one RR1 variable), and 8.35 ± 0.42 kpc (using our SX Phoenicis star detection in M 30). Fitting isochrones to the CMD, we estimate an age of 13.0 ± 1.0 Gyr for M 30. This work is based on data collected by MiNDSTEp with the Danish 1.54 m telescope at the ESO La Silla Observatory.The full light curves, an extract of which is shown in Table 2 are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/555/A36">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/555/A36</A>Tables 8-10, and Figs. 6 and 9 are available in electronic form at <A href="http://www.aanda.org">http://www.aanda.org</A>
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Kains, N.
Bramich, D. M.
Arellano Ferro, A.
Figuera Jaimes, R.
Jørgensen, U. G.
Giridhar, S.
Penny, M. T.
Alsubai, K. A.
Andersen, J. M.
Bozza, V.
Browne, P.
Burgdorf, M.
Calchi Novati, S.
Damerdji, Yassine ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Diehl, C.
Dodds, P.
Dominik, M.
Elyiv, Andrii ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Fang, X.-S.
Giannini, E.
Gu, S.-H.
Hardis, S.
Harpsøe, 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.
Rabus, M.
Rahvar, S.
Ricci, Davide ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Sahu, K.
Scarpetta, G.
Skottfelt, J.
Snodgrass, C.
Southworth, J.
Surdej, Jean  ;  Université de Liège - ULiège
Tregloan-Reed, J.
Vilela, C.
Wertz, Olivier ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Williams, A.
More authors (40 more) Less
Language :
English
Title :
Estimating the parameters of globular cluster M 30 (NGC 7099) from time-series photometry
Publication date :
01 July 2013
Journal title :
Astronomy and Astrophysics
ISSN :
0004-6361
eISSN :
1432-0746
Publisher :
EDP Sciences, Les Ulis, France
Volume :
555
Pages :
36
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 21 November 2013

Statistics


Number of views
74 (10 by ULiège)
Number of downloads
185 (1 by ULiège)

Scopus citations®
 
25
Scopus citations®
without self-citations
13
OpenCitations
 
17

Bibliography


Similar publications



Contact ORBi