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Start Over Subject photometry Validation Level 2
861. BVRI photometry of 234 spiral galaxies
ID:
ivo://CDS.VizieR/J/A+AS/118/111
Title:
BVRI photometry of 234 spiral galaxies
Short Name:
J/A+AS/118/111
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present V- and I-band CCD surface photometry on 234 inclined Sa-Sd galaxies, completed by similar data in B and R for a reduced subsample. In this first paper of a series, the reduction of the data is discussed, and several comparisons are made with other recent works. Radial profiles are presented for the surface brightness and the characteristics of ellipses fitted to isophotes; global, effective, and isophotal parameters are listed.
862. BVRI photometry of stars in BZ UMa field
ID:
ivo://CDS.VizieR/J/other/IBVS/5526
Title:
BVRI photometry of stars in BZ UMa field
Short Name:
J/other/IBVS/552
Date:
21 Oct 2021
Publisher:
CDS
Description:
The AAVSO has received 4270 CCD measurements of BZ UMa over four nights during its March, 2004 outburst. Analysis of the measurements reveals rapid flickering and quasiperiodic behaviour but no coherent periodicity (beyond the orbital period) and the notable absence of superhumps
863. BVRI photometry of stars in Orion A
ID:
ivo://CDS.VizieR/J/ApJ/764/114
Title:
BVRI photometry of stars in Orion A
Short Name:
J/ApJ/764/114
Date:
21 Oct 2021
Publisher:
CDS
Description:
We extend our previous study of the stellar population of L1641, the lower-density star-forming region of the Orion A cloud south of the dense Orion Nebula Cluster (ONC), with the goal of testing whether there is a statistically significant deficiency of high-mass stars in low-density regions. Previously, we compared the observed ratio of low-mass stars to high-mass stars with theoretical models of the stellar initial mass function (IMF) to infer a deficiency of the highest-mass stars in L1641. We expand our population study to identify the intermediate-mass (late B to G) L1641 members in an attempt to make a more direct comparison with the mass function of the nearby ONC. The spectral-type distribution and the K-band luminosity function of L1641 are similar to those of the ONC, but problems of incompleteness and contamination prevent us from making a detailed test for differences. We limit our analysis to statistical tests of the ratio of high-mass to low-mass stars, which indicate a probability of only 3% that the ONC and the southern region of L1641 were drawn from the same population, supporting the hypothesis that the upper-mass end of the IMF is dependent on environmental density.
864. BVRI photometry of Stock 1 stars
ID:
ivo://CDS.VizieR/J/PASP/114/1382
Title:
BVRI photometry of Stock 1 stars
Short Name:
J/PASP/114/1382
Date:
21 Oct 2021
Publisher:
CDS
Description:
BVRI photometry and J2000.0 positions have been obtained for stars in the field of the open cluster Stock 1. The photometry has been combined with available spectral types and proper motions to investigate cluster membership. We conclude that Stock 1 is a young cluster with a reddening of E(B-V)=0.16+/-0.04, a distance modulus of V_0_-M_V_=7.5+/-0.1, and an age of 300+/-50Myr.
865. BVRI photometry of the eclipsing binary BS Vul
ID:
ivo://CDS.VizieR/J/AJ/144/37
Title:
BVRI photometry of the eclipsing binary BS Vul
Short Name:
J/AJ/144/37
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a detailed study of the close eclipsing binary BS Vulpeculae. Although it is relatively bright (V: 10.9-11.6mag) and belongs to short-periodic variable stars (P=0.48days), it is rather neglected. To perform a thorough period analysis, we collected all available photometric observations that span the time interval of 1898-2010. Observations include archive photographic plate measurements and visually determined eclipse minima timings done in 1979-2003, which were later shown to be biased to accommodate the existing linear ephemeris. Applying our own direct period analysis we found a well-defined shortening of the orbital period of dP/dt=-6.70(17)x10^-11^=-2.11(6)ms/yr, which implies a continual mass flow from the primary to the secondary component. Using the 2003 version of the Wilson-Van Hamme code, our new complete BV(IR)_C_ light curves were analyzed and the physical parameters of the system were derived. We found that BS Vul is a near contact binary system with the primary component filling its critical Roche lobe. The luminosity enhancement on the left shoulder of the secondary minimum shown in the light curves can be explained as a result of a persistent hot spot on the secondary due to the mass transfer from the primary component to the secondary one and heating the facing hemisphere of the secondary component, which is consistent with our result of period analysis. With the period decrease, BS Vul will evolve toward the contact phase. It is another good observational example as predicted by the theory of thermal relaxation oscillations.
866. BVRI photometry of the Type II-P SN 2017eaw
ID:
ivo://CDS.VizieR/J/MNRAS/487/832
Title:
BVRI photometry of the Type II-P SN 2017eaw
Short Name:
J/MNRAS/487/832
Date:
21 Oct 2021
Publisher:
CDS
Description:
Broadband BVRI light curves of SN 2017eaw in NGC 6946 reveal the classic elements of a Type II-P supernova. The observations were begun on 16 May 2017 (UT), approximately 1 d after the discovery was announced, and the photometric monitoring was carried out over a period of nearly 600d. The light curves show a well-defined plateau and an exponential tail which curves slightly at later times. An approximation to the bolometric light curve is derived and used to estimate the amount of ^56^Ni created in the explosion; from various approaches described in the literature, we obtain M(^56^Ni)=0.115_-0.022_^+0.027^M_{sun}_. We also estimate that 43 per cent of the bolometric flux emitted during the plateau phase is actually produced by the ^56^Ni chain. Other derived parameters support the idea that the progenitor was a red supergiant.
867. BVRI photometry of V367 Cyg
ID:
ivo://CDS.VizieR/J/A+A/368/932
Title:
BVRI photometry of V367 Cyg
Short Name:
J/A+A/368/932
Date:
21 Oct 2021
Publisher:
CDS
Description:
New BVRI photoelectric observations of the interacting binary V367 Cyg were made during two consecutive seasons, 1996 and 1997, using the two-channel photometer at Mt. Suhora Observatory. Data left in the instrumental system and sorted with time of observations.
868. BVRI photom. of DV Psc and known short-period EBs
ID:
ivo://CDS.VizieR/J/ApJ/877/75
Title:
BVRI photom. of DV Psc and known short-period EBs
Short Name:
J/ApJ/877/75
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using 27 sets of new multiband photometry light curves acquired from our long-term photometric campaign carried out in the last 5yr and high-resolution spectroscopic data from seven nights, we analyzed the physical mechanisms of period variation, starspot cycle, optical flares, and chromospheric activities of the eclipsing binary DV Psc. Our updated O-C diagram covering a period of approximately 20yr shows an oscillation in its orbital period. This variations might be caused by a third body with an orbital period of 14.58+/-0.28yr. There are two active regions of starspots at longitude belts of about 90{deg} and 270{deg}. We obtained its starspot cycles with periods of 3.60+/-0.03yr and 3.42+/-0.02yr at about 90{deg} and 270{deg}, respectively. Moreover, the magnitude difference of Max.I-Max.II shows cyclic oscillation of 5.15+/-0.01yr. During our decade long photometric campaign, we observed DV Psc a total of 326.4hr, detected 18 outbursts (12 of them have never been reported) with flare energies in the range of (6.62-1106.85)x10^24^J. The slope of the relationship between the phase of the max flare and spots is 0.842 +/-0.083, implying a correlation between spots and flares. We discovered evidence for a correlation between the rotation period and the activity cycle for the short-period eclipsing binaries. Our high-resolution spectroscopic observations of DV Psc show obvious emissions above continuum in the H{alpha} line and small self-reversal emissions of the CaII IRT lines.
869. BVRIr photometry of HD 189733
ID:
ivo://CDS.VizieR/J/ApJ/650/1160
Title:
BVRIr photometry of HD 189733
Short Name:
J/ApJ/650/1160
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on the BVRI multiband follow-up photometry of the transiting extrasolar planet HD 189733b. We revise the transit parameters and find a planetary radius of Rp=1.154+/-0.033R_J_ and an inclination of i_P_=89.79+/-0.24{deg}. The new density (~1g/cm^3^) is significantly higher than the former estimate (~0.75g/cm^3^); this shows that from the current sample of nine transiting planets, only HD 209458 (and possibly OGLE-10b) have anomalously large radii and low densities. We note that due to the proximity of its parent star, HD 189733b currently has one of the most precise radius determinations among extrasolar planets. We calculate new ephemerides, P=2.218573+/-0.000020-days and T0=2453639.39420+/-0.00024 (HJD), and estimate the timing offsets of the 11 distinct transits with respect to the predictions of a constant orbital period, which can be used to reveal the presence of additional planets in the system.
870. BVRI+SDSS+2MASS and WISE photometry of 289 stars
ID:
ivo://CDS.VizieR/J/MNRAS/417/2230
Title:
BVRI+SDSS+2MASS and WISE photometry of 289 stars
Short Name:
J/MNRAS/417/2230
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present colour transformations for the conversion of the W1 and W2 magnitudes of the Wide-field Infrared Survey Explorer (WISE) photometric system to the Johnson-Cousins BVRI, Sloan Digital Sky Survey gri and Two-Micron All-Sky Survey JHKs photometric systems, for dwarfs.