Search

Start Over Capability Type Simple Cone Search
1811. BVRH{alpha} photometry of candidates Be stars
ID:
ivo://CDS.VizieR/J/ApJ/652/458
Title:
BVRH{alpha} photometry of candidates Be stars
Short Name:
J/ApJ/652/458
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present B, V, R, and H{alpha} photometry of eight clusters in the Small Magellanic Cloud, five in the Large Magellanic Cloud, and three Galactic clusters and use two-color diagrams (2-CDs) to identify candidate Be star populations in these clusters. We find evidence that the Be phenomenon is enhanced in low-metallicity environments, based on the observed fractional early-type candidate Be star content of clusters of age 10-25Myr.
1812. BVRHalpha photometry of NGC 1818
ID:
ivo://CDS.VizieR/J/A+A/317/448
Title:
BVRHalpha photometry of NGC 1818
Short Name:
J/A+A/317/448
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present B,V,R,Halpha CCD photometry and astrometry of Be stars in NGC 1818, its small neighbouring cluster NGC 1818B, and the surrounding field down to V = 18 mag. Our Be star identifiers conform to IAU specifications. For a description of the UBVRI and Halpha systems, see e.g. <GCPD/08> and <GCPD/55>
1813. BV(RI)c bands of Cepheids in IC 1613
ID:
ivo://CDS.VizieR/J/A+A/445/901
Title:
BV(RI)c bands of Cepheids in IC 1613
Short Name:
J/A+A/445/901
Date:
21 Oct 2021
Publisher:
CDS
Description:
A set of six BV(RI)c observations collected with the WFI at the ESO 2.2m telescope have been used to derive multicolor data of Cepheids in IC 1613 identified in previous surveys. Since part of the previously known data were obtained only in V,I filters or without filter (Wh) bands, the method of Freedman has been applied to get reliable mean intensity values of Cepheid magnitudes in the various bands. The resulting slopes of the relations in the BVI bands are similar, within the uncertainties, to those previously obtained by other authors for the LMC. The distribution of the Cepheids in the period-color diagrams is compatible with a change near P about 10d as observed in LMC. The distribution in the color-color diagrams is more similar to that in SMC, and this should be related to the very low metallicity of the galaxy.
1814. BVRI CCD photometry in the field of M 31
ID:
ivo://CDS.VizieR/II/208
Title:
BVRI CCD photometry in the field of M 31
Short Name:
II/208
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deep BVRI CCD photometry was performed on a 1 square degree region of M31. The observations were made between September 12 and September 27, 1990, using the McGraw-Hill 1.3m telescope at the Michigan-Dartmouth-MIT (MDM) observatory at Kitt Peak. The catalogue has typical completion limits of 22.3Bmag, 22.2Vmag, 22.2Rmag and 20.9Imag. Photometric accuracy is about 2% at Vmag=19. The final astrometric calibrations take into account the systematic error discovered in the Berkhuijsen etal (1987) catalog (Magnier etal 1993). They are in the J2000 system and are eventually tied to the HST Guide Star Catalog. The final photometric calibrations are tied via the NGC 206 region to photometry taken at the Michigan-Dartmouth-MIT (MDM) 1.3m in September and October 1993. These are tied to the Landolt (1992) system of standard stars, and are in the Johnson-Kron-Cousins system (BVRcIc).
1815. BVRI CCD photometry of 4 galaxy clusters
ID:
ivo://CDS.VizieR/J/other/BASI/30.911
Title:
BVRI CCD photometry of 4 galaxy clusters
Short Name:
J/other/BASI/30.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used the 2.3-meter Vainu Bappu Telescope to perform CCD imaging of X-ray-selected poor clusters of galaxies. Our sample consists of four X-ray luminous clusters in the Einstein Observatory Extended Medium Sensitivity Survey (EMSS) and noted by Gioia & Luppino (1994ApJS...94..583G) to be optically less rich than Abell clusters. The sample spans a redshift range of 0.08<=z<=0.22. We have assembled catalogs of galaxies detected in the cluster fields to a magnitude limit m_V_~22. This paper describes the data reduction performed on the CCD images, the methods used to construct the extended object catalogs, the photometric calibrations, and some understanding of their completeness and contamination.
1816. BVRI CCD photometry of NGC 5460
ID:
ivo://CDS.VizieR/J/A+AS/111/275
Title:
BVRI CCD photometry of NGC 5460
Short Name:
J/A+AS/111/275
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present CCD photometry on the BV(RI)_KC_ (Cape) photometric system of the core of the young open cluster, NGC 5460, to a magnitude limit V=~19, R=~19.5. We give photometry for 353 stars and identify 25 as cluster members along with a further 27 as possible members based on their positions in individual colour-magnitude diagrams. We estimate the reddening to the cluster and redefine its distance and age. Four stars are identified as possible variables and their nature discussed.
1817. BV(RI)_C_H{alpha} photometry of NGC 663
ID:
ivo://CDS.VizieR/J/A+A/376/144
Title:
BV(RI)_C_H{alpha} photometry of NGC 663
Short Name:
J/A+A/376/144
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new BV(RI)_C_H{alpha} photometry of the young open cluster NGC 663. The H{alpha} photometry is complete down to magnitude R_C_=15.4, corresponding to spectral type A5 for the cluster members. This allows detection of mild and strong H{alpha} emission in all B-type stars in the cluster. In addition to the 22 Be stars known in the observed field of NGC 663, we discovered four new faint stars of this type. We find that Be stars in NGC 663 cover the whole range of the B spectral type. They are, however, most populous among stars with spectral types falling in the range between B0 and B3, where their fraction amounts to 31+/-8%. Among B-type stars later than B3, Be stars are much less abundant: only 7 out of 101 observed stars, that is, 7+/-3%, were detected. About 70% of the observed Be stars in NGC 663 show detectable variations of light. In the time interval covered by our observations, the ranges of the largest variations reach 0.4mag in the I_C_ band. By means of the isochrone fitting, we derived the cluster distance of 2.1kpc, age of 20-25Myr, and the mean colour excess E(R-I)_C_=0.54mag, with a ~0.1mag scatter due to differential reddening.
1818. BV(RI)_C_JHK H{alpha} photometry in IC 5146
ID:
ivo://CDS.VizieR/J/AJ/123/304
Title:
BV(RI)_C_JHK H{alpha} photometry in IC 5146
Short Name:
J/AJ/123/304
Date:
21 Oct 2021
Publisher:
CDS
Description:
The B0V star BD+46 3474 lies near the front surface of a dense molecular cloud and illuminates the emission/reflection nebula IC 5146. The HAeBe variable BD +46 3471 is embedded in the same cloud, about 10' (3.5pc) away. CCD photometry in BV(RI)_C_ (to V=22) and in JHK (to about K=16.5) has been obtained for the young clusters surrounding each of these two bright stars. Some 100 emission-H{alpha} stars brighter than R=20.5 have been found in the area, most of them in IC 5146. (Among these are two that have spectra resembling a high-excitation Herbig-Haro [HH] object plus a stellar continuum).
1819. BV(RI)_C_photometry of 77 Hyades stars
ID:
ivo://CDS.VizieR/J/AJ/132/111
Title:
BV(RI)_C_photometry of 77 Hyades stars
Short Name:
J/AJ/132/111
Date:
21 Oct 2021
Publisher:
CDS
Description:
New BV(RI)C observations of 77 stars in the Hyades are reported and discussed. The new observations are used to test published magnitudes and color indices for that cluster. For values of (V-R)C and (R-I)C published previously by Taylor & Joner (1985AJ.....90..479T and 2005, Cat. <J/ApJS/159/100>), the tests reveal no detectable scale-factor problems. In addition, the tests show that possible zero-point corrections to the published data can be no larger than a few millimagnitudes. These test results indicate that future studies requiring precision photometry for Hyades stars would be well served by selecting data samples from sources as close as possible to the native Cousins system. Tests of B-V photometry published by Johnson & Knuckles (1955ApJ...122..209J) reveal a zero-point ambiguity of approximately 8mmag in the new data that will require further measurements to resolve.
1820. BVRIc photometry of Stock 8
ID:
ivo://CDS.VizieR/J/MNRAS/384/1675
Title:
BVRIc photometry of Stock 8
Short Name:
J/MNRAS/384/1675
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present UBVIc CCD photometry of the young open cluster Stock 8 with the aim of studying its basic properties such as the amount of interstellar extinction, distance, age, stellar contents and initial mass function (IMF). We also studied the star formation scenario in this region. From optical data, the radius of the cluster is found to be ~6arcmin (~3.6pc) and the reddening within the cluster region varies from E(B-V)=0.40 to 0.60mag. The cluster is located at a distance of 2.05+/-0.10kpc. Using H{alpha} slitless spectroscopy and Two Micron All Sky Survey (2MASS) near-infrared (NIR) data we identified H{alpha} emission and NIR-excess young stellar objects (YSOs), respectively.

Limit your search

more »

more »

more »

more »

more »

more »