The beat Cepheids in the Magellanic Clouds: An analysis from the EROS-2 database

J. B. Marquette; J. P. Beaulieu; J. R. Buchler; R. Szabó; P. Tisserand; S. Belghith; P. Fouqué; É Lesquoy; A. Milsztajn; A. Schwarzenberg-Czerny; C. Afonso; J. N. Albert; J. Andersen; R. Ansari; É Aubourg; P. Bareyre; X. Charlot; C. Coutures; R. Ferlet; J. F. Glicenstein; B. Goldman; A. Gould; D. Graff; M. Gros; J. Haïssinski; C. Hamadache; J. De Kat; L. Le Guillou; C. Loup; C. Magneville; É Maurice; A. Maury; M. Moniez; N. Palanque-Delabrouille; O. Perdereau; Y. R. Rahal; J. Rich; M. Spiro; A. Vidal-Madjar

doi:10.1051/0004-6361:200810842

The beat Cepheids in the Magellanic Clouds: An analysis from the EROS-2 database

J. B. Marquette, J. P. Beaulieu, J. R. Buchler, R. Szabó, P. Tisserand, S. Belghith, P. Fouqué, É Lesquoy, A. Milsztajn, A. Schwarzenberg-Czerny, C. Afonso, J. N. Albert, J. Andersen, R. Ansari, É Aubourg, P. Bareyre, X. Charlot, C. Coutures, R. Ferlet, J. F. GlicensteinB. Goldman, A. Gould, D. Graff, M. Gros, J. Haïssinski, C. Hamadache, J. De Kat, L. Le Guillou, C. Loup, C. Magneville, É Maurice, A. Maury, M. Moniez, N. Palanque-Delabrouille, O. Perdereau, Y. R. Rahal, J. Rich, M. Spiro, A. Vidal-Madjar

Research output: Contribution to journal › Article › peer-review

24 Citations (Scopus)

Abstract

Context. A number of microlensing dark-matter surveys have produced tens of millions of light curves of individual background stars. These data provide an unprecedented opportunity for systematic studies of whole classes of variable stars and their host galaxies.Aims. We aim to use the EROS-2 survey of the Magellanic Clouds to detect and study the population of beat Cepheids (BCs) in both Clouds. BCs pulsating simultaneously in the first overtone and fundamental modes (FO/F) or in the second and first overtone modes (SO/FO) are of particular interest.Methods. Using special software designed to search for periodic variables, we have scanned the EROS-2 data base for variables in the typical period range of Cepheids. Metallicities of FO/F objects were then calculated from linear nonadiabatic convective stellar models.Results. We identify 74 FO/F BCs in the LMC and 41 in the SMC, and 173 and 129 SO/FO pulsators in the LMC and SMC, respectively; 185 of these stars are new discoveries. For nearly all the FO/F objects we determine minimum, mean, and maximum values of the metallicity.Conclusions. The EROS data have expanded the samples of known BCs in the LMC by 31%, in the SMC by 110%. The FO/F objects provide independent measures of metallicities in these galaxies. The mean value of metallicity is 0.0045 in the LMC and 0.0018 in the SMC.

Original language	English
Pages (from-to)	249-256
Number of pages	8
Journal	Astronomy and Astrophysics
Volume	495
Issue number	1
DOIs	https://doi.org/10.1051/0004-6361:200810842
Publication status	Published - Feb 2009

Access to Document

10.1051/0004-6361:200810842

Cite this

Marquette, J. B., Beaulieu, J. P., Buchler, J. R., Szabó, R., Tisserand, P., Belghith, S., Fouqué, P., Lesquoy, É., Milsztajn, A., Schwarzenberg-Czerny, A., Afonso, C., Albert, J. N., Andersen, J., Ansari, R., Aubourg, É., Bareyre, P., Charlot, X., Coutures, C., Ferlet, R., ... Vidal-Madjar, A. (2009). The beat Cepheids in the Magellanic Clouds: An analysis from the EROS-2 database. Astronomy and Astrophysics, 495(1), 249-256. https://doi.org/10.1051/0004-6361:200810842

@article{89adb0fd89424c32ab7a67670ec7f604,

title = "The beat Cepheids in the Magellanic Clouds: An analysis from the EROS-2 database",

abstract = "Context. A number of microlensing dark-matter surveys have produced tens of millions of light curves of individual background stars. These data provide an unprecedented opportunity for systematic studies of whole classes of variable stars and their host galaxies.Aims. We aim to use the EROS-2 survey of the Magellanic Clouds to detect and study the population of beat Cepheids (BCs) in both Clouds. BCs pulsating simultaneously in the first overtone and fundamental modes (FO/F) or in the second and first overtone modes (SO/FO) are of particular interest.Methods. Using special software designed to search for periodic variables, we have scanned the EROS-2 data base for variables in the typical period range of Cepheids. Metallicities of FO/F objects were then calculated from linear nonadiabatic convective stellar models.Results. We identify 74 FO/F BCs in the LMC and 41 in the SMC, and 173 and 129 SO/FO pulsators in the LMC and SMC, respectively; 185 of these stars are new discoveries. For nearly all the FO/F objects we determine minimum, mean, and maximum values of the metallicity.Conclusions. The EROS data have expanded the samples of known BCs in the LMC by 31%, in the SMC by 110%. The FO/F objects provide independent measures of metallicities in these galaxies. The mean value of metallicity is 0.0045 in the LMC and 0.0018 in the SMC.",

keywords = "Cepheids, Magellanic Clouds",

author = "Marquette, {J. B.} and Beaulieu, {J. P.} and Buchler, {J. R.} and R. Szab{\'o} and P. Tisserand and S. Belghith and P. Fouqu{\'e} and {\'E} Lesquoy and A. Milsztajn and A. Schwarzenberg-Czerny and C. Afonso and Albert, {J. N.} and J. Andersen and R. Ansari and {\'E} Aubourg and P. Bareyre and X. Charlot and C. Coutures and R. Ferlet and Glicenstein, {J. F.} and B. Goldman and A. Gould and D. Graff and M. Gros and J. Ha{\"i}ssinski and C. Hamadache and {De Kat}, J. and {Le Guillou}, L. and C. Loup and C. Magneville and {\'E} Maurice and A. Maury and M. Moniez and N. Palanque-Delabrouille and O. Perdereau and Rahal, {Y. R.} and J. Rich and M. Spiro and A. Vidal-Madjar",

year = "2009",

month = feb,

doi = "10.1051/0004-6361:200810842",

language = "English",

volume = "495",

pages = "249--256",

journal = "Astronomy and Astrophysics",

issn = "0004-6361",

publisher = "EDP Sciences",

number = "1",

}

Marquette, JB, Beaulieu, JP, Buchler, JR, Szabó, R, Tisserand, P, Belghith, S, Fouqué, P, Lesquoy, É, Milsztajn, A, Schwarzenberg-Czerny, A, Afonso, C, Albert, JN, Andersen, J, Ansari, R, Aubourg, É, Bareyre, P, Charlot, X, Coutures, C, Ferlet, R, Glicenstein, JF, Goldman, B, Gould, A, Graff, D, Gros, M, Haïssinski, J, Hamadache, C, De Kat, J, Le Guillou, L, Loup, C, Magneville, C, Maurice, É, Maury, A, Moniez, M, Palanque-Delabrouille, N, Perdereau, O, Rahal, YR, Rich, J, Spiro, M & Vidal-Madjar, A 2009, 'The beat Cepheids in the Magellanic Clouds: An analysis from the EROS-2 database', Astronomy and Astrophysics, vol. 495, no. 1, pp. 249-256. https://doi.org/10.1051/0004-6361:200810842

TY - JOUR

T1 - The beat Cepheids in the Magellanic Clouds

T2 - An analysis from the EROS-2 database

AU - Marquette, J. B.

AU - Beaulieu, J. P.

AU - Buchler, J. R.

AU - Szabó, R.

AU - Tisserand, P.

AU - Belghith, S.

AU - Fouqué, P.

AU - Lesquoy, É

AU - Milsztajn, A.

AU - Schwarzenberg-Czerny, A.

AU - Afonso, C.

AU - Albert, J. N.

AU - Andersen, J.

AU - Ansari, R.

AU - Aubourg, É

AU - Bareyre, P.

AU - Charlot, X.

AU - Coutures, C.

AU - Ferlet, R.

AU - Glicenstein, J. F.

AU - Goldman, B.

AU - Gould, A.

AU - Graff, D.

AU - Gros, M.

AU - Haïssinski, J.

AU - Hamadache, C.

AU - De Kat, J.

AU - Le Guillou, L.

AU - Loup, C.

AU - Magneville, C.

AU - Maurice, É

AU - Maury, A.

AU - Moniez, M.

AU - Palanque-Delabrouille, N.

AU - Perdereau, O.

AU - Rahal, Y. R.

AU - Rich, J.

AU - Spiro, M.

AU - Vidal-Madjar, A.

PY - 2009/2

Y1 - 2009/2

N2 - Context. A number of microlensing dark-matter surveys have produced tens of millions of light curves of individual background stars. These data provide an unprecedented opportunity for systematic studies of whole classes of variable stars and their host galaxies.Aims. We aim to use the EROS-2 survey of the Magellanic Clouds to detect and study the population of beat Cepheids (BCs) in both Clouds. BCs pulsating simultaneously in the first overtone and fundamental modes (FO/F) or in the second and first overtone modes (SO/FO) are of particular interest.Methods. Using special software designed to search for periodic variables, we have scanned the EROS-2 data base for variables in the typical period range of Cepheids. Metallicities of FO/F objects were then calculated from linear nonadiabatic convective stellar models.Results. We identify 74 FO/F BCs in the LMC and 41 in the SMC, and 173 and 129 SO/FO pulsators in the LMC and SMC, respectively; 185 of these stars are new discoveries. For nearly all the FO/F objects we determine minimum, mean, and maximum values of the metallicity.Conclusions. The EROS data have expanded the samples of known BCs in the LMC by 31%, in the SMC by 110%. The FO/F objects provide independent measures of metallicities in these galaxies. The mean value of metallicity is 0.0045 in the LMC and 0.0018 in the SMC.

AB - Context. A number of microlensing dark-matter surveys have produced tens of millions of light curves of individual background stars. These data provide an unprecedented opportunity for systematic studies of whole classes of variable stars and their host galaxies.Aims. We aim to use the EROS-2 survey of the Magellanic Clouds to detect and study the population of beat Cepheids (BCs) in both Clouds. BCs pulsating simultaneously in the first overtone and fundamental modes (FO/F) or in the second and first overtone modes (SO/FO) are of particular interest.Methods. Using special software designed to search for periodic variables, we have scanned the EROS-2 data base for variables in the typical period range of Cepheids. Metallicities of FO/F objects were then calculated from linear nonadiabatic convective stellar models.Results. We identify 74 FO/F BCs in the LMC and 41 in the SMC, and 173 and 129 SO/FO pulsators in the LMC and SMC, respectively; 185 of these stars are new discoveries. For nearly all the FO/F objects we determine minimum, mean, and maximum values of the metallicity.Conclusions. The EROS data have expanded the samples of known BCs in the LMC by 31%, in the SMC by 110%. The FO/F objects provide independent measures of metallicities in these galaxies. The mean value of metallicity is 0.0045 in the LMC and 0.0018 in the SMC.

KW - Cepheids

KW - Magellanic Clouds

UR - http://www.scopus.com/inward/record.url?scp=60849098205&partnerID=8YFLogxK

U2 - 10.1051/0004-6361:200810842

DO - 10.1051/0004-6361:200810842

M3 - Article

SN - 0004-6361

VL - 495

SP - 249

EP - 256

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

IS - 1

ER -

The beat Cepheids in the Magellanic Clouds: An analysis from the EROS-2 database

Abstract

Access to Document

Other files and links

Fingerprint

Cite this