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151. BVIc photometry of Cepheids from ASAS-3 catalog
ID:
ivo://CDS.VizieR/J/AZh/88/886
Title:
BVIc photometry of Cepheids from ASAS-3 catalog
Short Name:
J/AZh/88/886
Date:
21 Oct 2021
Publisher:
CDS
Description:
In 2008-2010, we obtained 6095 CCD frames in the BVIc photometric system for 49 classical Cepheids discovered in the ASAS-3 project. The observations were obtained on the 76-cm telescope of the South African Astronomical Observatory (SAAO, RSA) and the 40-cm telescope of the Cerro Armazones Observatory of the Catholic University of the North (OCA, Chile), with a SBIGCCD ST-10XME camera. We present tabulated observations, light curves, and revised elements for the brightness variations.
152. BVI light curves of RZ Lyr
ID:
ivo://CDS.VizieR/J/MNRAS/423/993
Title:
BVI light curves of RZ Lyr
Short Name:
J/MNRAS/423/993
Date:
21 Oct 2021
Publisher:
CDS
Description:
The analysis of recent, extended multicolour CCD and archive photoelectric, photographic and visual observations has revealed several important properties of RZ Lyr, an RRab-type variable exhibiting large-amplitude Blazhko modulation. On the time base of ~110yr, a strict anticorrelation between the pulsation- and modulation-period changes is established. The light curve of RZ Lyr shows a remarkable bump on the descending branch in the small-amplitude phase of the modulation, similarly to the light curves of bump Cepheids. We speculate that the stellar structure temporally suits a 4:1 resonance between the periods of the fundamental and one of the higher order radial modes in this modulation phase. The light-curve variation of RZ Lyr can be correctly fitted with a two-modulation-component solution; the 121-d period of the main modulation is nearly but not exactly four times longer than the period of the secondary modulation component. Using the inverse photometric method, the variations in the pulsation-averaged values of the physical parameters in different phases of both modulation components are determined.
153. BVI photometric variability survey of M3
ID:
ivo://CDS.VizieR/J/AJ/129/1596
Title:
BVI photometric variability survey of M3
Short Name:
J/AJ/129/1596
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted a three-band (BVI) variability survey of the globular cluster M3. This is the first three-band survey of the cluster using modern image subtraction techniques. Observations were made over nine nights in 1998 on the 1.2m telescope at the F. L. Whipple Observatory in Arizona. We present photometry for 180 variable stars in the M3 field, 12 of which are newly discovered. New discoveries include six SX Phoenicis-type variables that all lie in the blue straggler region of the color-magnitude diagram, two new first-overtone RR Lyrae variables, a candidate multimode RR Lyrae variable, a detached eclipsing binary, and two unclassified variables. We also provide revised periods for 52 of the 168 previously known variables that we observe.
154. BVI photometry of Cepheids in M81
ID:
ivo://CDS.VizieR/J/ApJ/743/176
Title:
BVI photometry of Cepheids in M81
Short Name:
J/ApJ/743/176
Date:
21 Oct 2021
Publisher:
CDS
Description:
We identify and phase a sample of 107 Cepheids with 10days<P<100days in M81 (NGC 3031) using the Large Binocular Telescope and calibrate their B, V, and I mean magnitudes with archival Hubble Space Telescope (HST) data. The use of a ground-based telescope to identify and phase the Cepheids and HST only for the final calibration reduces the demand on this highly oversubscribed spacecraft by nearly an order of magnitude and yields period-luminosity (PL) relations with dispersions comparable to the best LMC samples. We fit the sample using the OGLE-II LMC PL relations and are unable to find a self-consistent distance for different band combinations or radial locations within M81. We find a distance modulus for M81, relative to the LMC, of {mu}M_81_-{mu}_LMC_=9.39+/-0.14mag, including uncertainties due to the metallicity corrections. This corresponds to a distance to M81 of 3.6+/-0.2Mpc, assuming an LMC distance modulus of 18.41mag.
155. BVI photometry of Galactic Cepheids
ID:
ivo://CDS.VizieR/J/A+A/404/423
Title:
BVI photometry of Galactic Cepheids
Short Name:
J/A+A/404/423
Date:
21 Oct 2021
Publisher:
CDS
Description:
321 Galactic fundamental-mode Cepheids with good B,V,I photometry by Berdnikov et al. (2000, Cat. <J/A+AS/143/211>) and with homogenized color excesses E(B-V) based on Fernie et al. (1995IBVS.4148....1F) are used to determine their period-colour relation in the range 0.4<log P<1.6. Distances of 25 Cepheids in open clusters (Feast, 1999PASP..111..775F) and of 28 Cepheids with BBW distances (Gieren et al., 1998ApJ...496...17G) are used in a first step to determine the absorption coefficients R_B_=4.17, R_V_=3.17, and R_I_=1.89. The two sets define two independent P-L relations which agree very well in slope. They are therefore combined into a single mean Galactic P-L relation.
156. BVI photometry of LMC bar variables
ID:
ivo://CDS.VizieR/J/A+A/430/603
Title:
BVI photometry of LMC bar variables
Short Name:
J/A+A/430/603
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Johnson-Cousins B,V and I time series data obtained for 162 variable stars (135 RR Lyrae, 4 candidate Anomalous Cepheids, 11 Classical Cepheids, 11 eclipsing binaries and 1 delta Scuti star) in two 13x13 square arcmin areas close to the bar of the Large Magellanic Cloud. The photometric observations presented in this paper were carried out at the 1.54m Danish telescope located in La Silla, Chile, on the nights 4-7 January 1999, UT, and 23-24 January 2001, UT, respectively. In the paper we give coordinates, finding charts, periods, epochs, amplitudes, and mean quantities (intensity- and magnitude-averaged luminosities) of the variables with full coverage of the light variations, along with a discussion of the pulsation properties of the RR Lyrae stars in the sample.
157. BVI photometry of LMC Be stars
ID:
ivo://CDS.VizieR/J/MNRAS/361/1055
Title:
BVI photometry of LMC Be stars
Short Name:
J/MNRAS/361/1055
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue with coordinates and photometric data of 2446 Be star candidates in the Large Magellanic Cloud (LMC), based on a search of the OGLE II data base. The I-band light curves of these stars show outbursts in 24% of the sample (Type-1 stars), high and low states in 10%, periodic variations in 6% (Type-3 stars), and stochastic variations in 60% of the cases. We report on the result of the statistical study of light curves of Type-1 and Type-3 stars in the LMC, and the comparison with the previously reported results of the Small Magellanic Cloud (SMC) sample.
158. BVI photometry of NGC 4258 Cepheids
ID:
ivo://CDS.VizieR/J/ApJ/652/1133
Title:
BVI photometry of NGC 4258 Cepheids
Short Name:
J/ApJ/652/1133
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present initial results from a time series BVI survey of two fields in NGC 4258 using the HST ACS. This galaxy was selected because of its accurate maser-based distance, which is anticipated to have a total uncertainty of 3%. The goal of the HST observations is to provide an absolute calibration of the Cepheid distance scale and to measure its dependence on chemical abundance (the so-called metallicity effect). We carried out observations of two fields at different galactocentric distances with a mean abundance difference of 0.5dex. We discovered a total of 281 Cepheids with periods ranging from 4 to 45 days (the duration of our observing window).
159. BVI photometry of OGLE LMC Cepheids
ID:
ivo://CDS.VizieR/J/AcA/49/223
Title:
BVI photometry of OGLE LMC Cepheids
Short Name:
J/AcA/49/223
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Catalog of Cepheids from the LMC. The Catalog contains 1333 objects detected in the 4.5 square degree area of central parts of the LMC. About 3.4*10^5^ BVI measurements of these stars were collected during the OGLE-II microlensing survey. The Catalog data include period, BVI photometry, astrometry, and R_21_, phi_21_ parameters of the Fourier decomposition of I-band light curve. The vast majority of objects from the Catalog are the classical Cepheids pulsating in the fundamental or first overtone mode. The remaining objects include Population II Cepheids and red giants with pulsation-like light curves. Tests of completeness performed in overlapping parts of adjacent fields indicate that completeness of the Catalog is very high: >96%. Statistics and distributions of basic parameters of Cepheids are also presented. Finally, we show the light curves of three eclipsing systems containing Cepheid detected among objects of the Catalog. All presented data, including individual BVI observations are available from the OGLE Internet archive at URL: ftp://sirius.astrouw.edu.pl/ogle/ogle2/var_stars/lmc/cep/catalog/
160. BVI photometry of OGLE SMC Cepheids
ID:
ivo://CDS.VizieR/J/AcA/49/437
Title:
BVI photometry of OGLE SMC Cepheids
Short Name:
J/AcA/49/437
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Catalog of Cepheids from the SMC which contains data for 2049 objects detected in the 2.4 square degree area of central parts of the SMC. For each object period, BVI photometry, astrometry, and R_21_, {phi}_21_ parameters of the Fourier decomposition of I-band light curve are provided. The Catalog is based on observations collected during the OGLE-II microlensing survey. Tests of completeness performed in overlapping parts of adjacent fields indicate that completeness of the Catalog is very high: approx 92%. Statistics and distributions of basic parameters of Cepheids are also presented. All presented data, including individual BVI observations (approx 4.7*10^5^ BVI measurements), are available from the OGLE Internet archive at URL: ftp://sirius.astrouw.edu.pl/ogle/ogle2/var_stars/smc/cep/catalog