Observation of periodic variable stars towards the galactic spiral arms by EROS II

Abstract

We present the results of a massive variability search based on a photometric survey of a six square degree region along the Galactic plane at ($l=305^{\circ }$, $b=-0.8^{\circ }$) and ($l=330^{\circ }$, $b=-2.5^{\circ }$). This survey was performed in the framework of the EROS II (Expérience de Recherche d'Objets Sombres) microlensing program. The variable stars were found among 1,913,576 stars that were monitored between April and June 1998 in two passbands, with an average of 60 measurements. A new period-search technique is proposed which makes use of a statistical variable that characterizes the overall regularity of the flux versus phase diagram. This method is well suited when the photometric data are unevenly distributed in time, as is our case. 1,362 objects whose luminosity varies were selected. Among them we identified 9 Cepheids, 19 RR Lyrae, 34 Miras, 176 eclipsing binaries and 266 Semi-Regular stars. Most of them are newly identified objects. The cross-identification with known catalogues has been performed. The mean distance of the RR Lyrae is estimated to be $\sim 4.9\pm 0.3$ kpc undergoing an average absorption of $\sim 3.4\pm 0.2$ magnitudes. This distance is in good agreement with the one of disc stars which contribute to the microlensing source star population.Our catalogue and light curves are available electronically from the CDS, Strasbourg and from our Web site http://eros.in2p3.fr.

15 pages, 11 figures, accepted in A&A (april 2002)

References in corpus (6)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Extinction Map of Baade's Window
• Variability and spectral classification of LMC giants: results from DENIS and EROS
• Systematics of RR Lyrae Statistical Parallax III: Apparent Magnitudes and Extinctions
• Observation of Microlensing towards the Galactic Spiral Arms. EROS II 3 year survey
• On the Spatial Distribution of Stellar Populations in the Large Magellanic Cloud

Cited by in corpus (24)

• The ASAS-SN Catalog of Variable Stars I: The Serendipitous Survey
• The ASAS-SN Catalog of Variable Stars III: Variables in the Southern TESS Continuous Viewing Zone
• Structure Function Analysis of Long Term Quasar Variability
• A population of eruptive variable protostars in VVV
• The ASAS-SN Catalog of Variable Stars V: Variables in the Southern Hemisphere
• The ASAS-SN Catalog of Variable Stars IX: The Spectroscopic Properties of Galactic Variable Stars
• The ASAS-SN Catalog of Variable Stars X: Discovery of 116,000 New Variable Stars Using g-band Photometry
• The ASAS-SN Catalog of Variable Stars VII: Contact Binaries are Different Above and Below the Kraft Break
• An improved quasar detection method in EROS-2 and MACHO LMC datasets
• EROS 2 photometry of probable R Coronae Borealis stars in the Small Magellanic Cloud
• The Wendelstein Calar Alto Pixellensing Project (WeCAPP): The M31 Variable Star Catalogue
• Long Period Variables in the Large Magellanic Cloud from the EROS-2 survey
• A Mid-infrared Study of RR Lyrae Stars with the WISE All-Sky Data Release
• Meta Classification for Variable Stars
• Variable star classification across the Galactic bulge and disc with the VISTA Variables in the Vía Láctea survey
• The beat Cepheids in the Magellanic Clouds: an analysis from the EROS-2 database
• Accurate OH Maser Positions From The SPLASH Survey III: The Final 96 Square Degrees
• Citizen ASAS-SN Data Release I: Variable Star Classification Using Citizen Science
• Results from the Wide Angle Search for Planets Prototype (WASP0) II: Stellar Variability in the Pegasus Field
• The Berlin Exoplanet Search Telescope II. Catalog of Variable Stars. I. Characterization of Three Southern Target Fields
• Oxygen- and carbon-rich variable red giant populations in the Magellanic Clouds from EROS, OGLE, MACHO, and 2MASS photometry
• The TAOS Project Stellar Variability II. Detection of 15 Variable Stars
• Discovery of a peculiar Cepheid-like star towards the northern edge of the Small Magellanic Cloud
• EROS light curve data base