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4651. OGLE2 Mira variables in the Galactic bulge
ID:
ivo://CDS.VizieR/J/MNRAS/364/117
Title:
OGLE2 Mira variables in the Galactic bulge
Short Name:
J/MNRAS/364/117
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have extracted a total of 1968 Mira variables from the Optical Gravitational Lensing Experiment II (OGLE-II) data base in the Galactic bulge region. Among them, 1960 are associated with 2 Micron All-sky Survey (2MASS) sources, and 1541 are further identified with Midcourse Space Exploration (MSX) point sources. Their photometric properties are compared with those of Mira variables in the Large and Small Magellanic Clouds. We have found that mass-losing stars with circumstellar matter are reddened such that the colour dependence of the absorption coefficient is similar to that of interstellar matter. We also discuss the structure of the bulge. The surface number density of the bulge Mira variables is well correlated with the 2.2-m surface brightness obtained by the Cosmic Background Explorer (COBE) satellite. Using this relation, the total number of Mira variables in the bulge is estimated to be about 6x10^5^. The logP-K relation of the Mira variables gives their space distribution which supports the well-known asymmetry of the bar-like bulge.
4652. OGLE miscellaneous variable stars
ID:
ivo://CDS.VizieR/J/AcA/46/389
Title:
OGLE miscellaneous variable stars
Short Name:
J/AcA/46/389
Date:
21 Oct 2021
Publisher:
CDS
Description:
The first catalog of chromospherically active and ellipsoidal variable stars in the OGLE database is presented. The periods, the observed magnitudes and colors, their values free of interstellar extinction, and Fourier coefficients of light modulation are given for 549 stars. New color-magnitude diagrams based on new color determinations are presented. The chromospherically active stars are all among the bulge red giants, while the ellipsoidal binary stars are near the disk main sequence turn-off point. A discovery of a small group of very red (2<(V-I)_0_<6) and bright, chromospherically active bulge giants (I_0_=13mag) is also reported.
4653. OGLE, MOA & KMTNet RI light curve of KMT-2019-BLG-1715
ID:
ivo://CDS.VizieR/J/AJ/161/270
Title:
OGLE, MOA & KMTNet RI light curve of KMT-2019-BLG-1715
Short Name:
J/AJ/161/270
Date:
16 Mar 2022 00:06:48
Publisher:
CDS
Description:
We investigate the gravitational microlensing event KMT-2019-BLG-1715, the light curve of which shows two short-term anomalies from a caustic-crossing binary-lensing light curve: one with a large deviation and the other with a small deviation. We identify five pairs of solutions, in which the anomalies are explained by adding an extra lens or source component in addition to the base binary-lens model. We resolve the degeneracies by applying a method in which the measured flux ratio between the first and second source stars is compared with the flux ratio deduced from the ratio of the source radii. Applying this method leaves a single pair of viable solutions, in both of which the major anomaly is generated by a planetary-mass third body of the lens, and the minor anomaly is generated by a faint second source. A Bayesian analysis indicates that the lens comprises three masses: a planet-mass object with ~2.6M_J_ and binary stars of K and M dwarfs lying in the galactic disk. We point out the possibility that the lens is the blend, and this can be verified by conducting high-resolution follow-up imaging for the resolution of the lens from the source.
4654. OGLE RR Lyrae in LMC
ID:
ivo://CDS.VizieR/J/AcA/53/93
Title:
OGLE RR Lyrae in LMC
Short Name:
J/AcA/53/93
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the catalog of RR Lyr stars discovered in a 4.5 square degrees area in the central parts of the Large Magellanic Cloud (LMC). Presented sample contains 7612 objects, including 5455 fundamental mode pulsators (RRab), 1655 first-overtone (RRc), 272 second-overtone (RRe) and 230 double-mode RR Lyr stars (RRd). Additionally we attach alist of several dozen other short-period pulsating variables. The catalog data include astrometry, periods, BVI photometry, amplitudes, and parameters of the Fourier decomposition of the I-band light curve of each object. We provide a list of six LMC star clusters which contain RR Lyr stars. The richest cluster, NGC 1835, hosts 84 RR Lyr variables. The period distribution of these stars suggests that NGC1835 shares features of Oosterhoff type I and type II groups. All presented data, including individual BVI observations and finding charts are available from the OGLE Internet archive at ftp://sirius.astrouw.edu.pl/ogle/ogle2/var_stars/lmc/rrlyr
4655. OGLE RR Lyrae VI photometry
ID:
ivo://CDS.VizieR/J/AcA/48/113
Title:
OGLE RR Lyrae VI photometry
Short Name:
J/AcA/48/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze the mean luminosity of three samples of field RRab Lyr stars observed in the course of the OGLE microlensing experiment: 73 stars from the Galactic bulge and 110 and 128 stars from selected fields in the LMC and SMC, respectively. The fields are the same as in the recent distance determination to the Magellanic Clouds with the red clump stars method by Udalski et al. (1998AcA....48....1U). We determine the relative distance scale Galactic Bulge: 0.194+/-0.010; LMC: 1.00 ; SMC: 1.30+/-0.08. We calibrate our RR Lyr distance scale with the recent calibration of Gould and Popowski (1998ApJ...508..844G) based on statistical parallaxes. We obtain the following distance moduli to the Galactic bulge, LMC and SMC: m-M=14.5+/-0.15, m-M=18.09+/-0.16 and m-M=18.66+/-0.16mag.
4656. OGLE RR Lyr stars in omega Cen
ID:
ivo://CDS.VizieR/J/A+AS/125/343
Title:
OGLE RR Lyr stars in omega Cen
Short Name:
J/A+AS/125/343
Date:
21 Oct 2021
Publisher:
CDS
Description:
Table 1 lists light curve parameters and rectangular coordinates for variables OGLEGC 71-211. Table 2 contains equatorial coordinates of variables OGLEGC 71-211. Tables (table3 to 203) contain V-band light curves for variables OGLEGC71-211.
4657. OGLE SMC BVI photometry
ID:
ivo://CDS.VizieR/J/AcA/48/147
Title:
OGLE SMC BVI photometry
Short Name:
J/AcA/48/147
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present three color, BVI maps of the Small Magellanic Cloud. The maps contain precise photometric and astrometric data for about 2.2million stars from the central regions of the SMC bar covering ~2.4 square degrees on the sky. Mean brightness of stars is derived from observations collected in the course of the OGLE-II microlensing search from about 130, 30 and 15 measurements in the I, V and B-bands, respectively. Accuracy of the zero points of photometry is about 0.01mag, and astrometry 0.15arcsec (with possible systematic error up to 0.7arcsec). Color magnitude diagrams of observed fields are also presented. The maps of the SMC are the first from the series of similar maps covering other OGLE fields: LMC, Galactic bulge and Galactic disk. The data are very well suited for many projects, particularly for the SMC which has been neglected photometrically for years.
4658. OGLE SMC clusters
ID:
ivo://CDS.VizieR/J/AcA/48/175
Title:
OGLE SMC clusters
Short Name:
J/AcA/48/175
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the catalog of clusters found in the area of ~2.4 square degrees in the central region of the Small Magellanic Cloud. The catalog contains data for 238 clusters, 72 of them are new objects. For each cluster equatorial coordinates, radii, approximate number of members, cross-identification, finding chart and color magnitude diagrams: V-(B-V) and V-(V-I) are provided.
4659. OGLE2-TR-L9 g'r'i'z' light curves
ID:
ivo://CDS.VizieR/J/A+A/522/A29
Title:
OGLE2-TR-L9 g'r'i'z' light curves
Short Name:
J/A+A/522/A29
Date:
21 Oct 2021
Publisher:
CDS
Description:
Repeated observations of exoplanet transits allow us to refine the planetary parameters and probe them for any time dependent variations. In particular deviations of the period from a strictly linear ephemeris, transit timing variations (TTVs), can indicate the presence of additional bodies in the planetary system. Aims: Our goal was to reexamine the largely unstudied OGLE2-TR-L9 system with high cadence, multi-color photometry in order to refine the planetary parameters and probe the system for TTVs. From our analysis we find that the semi-major axis and the inclination differ from the previously published values. With the newly observed transits, we were able to refine the ephemeris to 2454492.80008(+/-0.00014) +2.48553417(+/-6.4)x10^-7^E. The newly derived parameters are a=0.0418(+/-0.0015)AU, r_p_=1.67(+/-0.05) R_j_, and inc=82.47{deg}(+/-0.12), differing significantly in a and inc from the previously published values. Within our data, we find indications for TTVs.
4660. OGLE-TR-10 u', g' and i'-band photometry
ID:
ivo://CDS.VizieR/J/A+A/505/901
Title:
OGLE-TR-10 u', g' and i'-band photometry
Short Name:
J/A+A/505/901
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report a stellar flare occurring during a transit of the exoplanet OGLE-TR-10b, an event not previously reported in the literature. This reduces the observed transit depth, particularly in the u'-band, but flaring could also be significant in other bands and could lead to incorrect planetary parameters. We suggest that OGLE-TR-10a is an active planet-hosting star and has an unusually high X-ray luminosity.