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- ID:
- ivo://CDS.VizieR/J/A+A/454/179
- Title:
- BVR phot. of Basel 11b, King 14, Czernik 43
- Short Name:
- J/A+A/454/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To progress in galactic studies based on open clusters, e.g. cluster formation rate or kinematical properties, one needs to improve the number of open clusters observed. However, only half of the 1700 known galactic open clusters have been properly observed so far, making any statistical investigation insignificant, especially at larger distances from the Sun. We study marginally investigated or neglected open clusters with Bessell CCD BVR photometry, whose data were used to fit isochrones to the individual color-magnitude diagrams. We examined the galactic clusters Basel 11b, King 14 and Czernik 43, the last being observed for the first time to this extent. As well as a careful comparison to available photometry, their parameters such as age, interstellar reddening, distance and apparent diameter were determined. The obtained cluster properties were verified by near infrared 2MASS data. The three investigated intermediate age clusters are all located in the galactic disk with distances between 1.8 and 3.0kpc from the Sun.
- ID:
- ivo://CDS.VizieR/J/A+A/436/117
- Title:
- BVR photometry in N214C
- Short Name:
- J/A+A/436/117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the Large Magellanic Cloud HII region N 214C using imaging and spectroscopy obtained at the ESO New Technology Telescope. On the basis of the highest resolution images so far obtained of the OB association LH 110, we show that the main exciting source of the HII region, Sk -71 51, is in fact a tight cluster of massive stars consisting of at least 6 components in an area ~4" wide. Spectroscopic observations allow us to revise the spectral type of the main component (#17) to O2V((f*))+OB, a very rare, hot type. We also classify several other stars associated with N 214C and study the extinction and excitation characteristics of the HII region. Moreover, we obtain BVR photometry and astrometry of 2365 stars and from the corresponding color-magnitude diagram study the stellar content of N 214C and the surrounding LH 110. Furthermore, we discover a striking compact blob of ionized gas in the outer northern part of N 214C. A spherical structure of ~5", in radius (~1.3pc), it is split into two lobes by absorbing dust running diametrically through its center. We discuss the possible nature of this object.
- ID:
- ivo://CDS.VizieR/J/AJ/131/1032
- Title:
- BVR photometry of BO CVn and SS Com
- Short Name:
- J/AJ/131/1032
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- BO CVn and SS Com are two short-period W UMa-type binary stars with spectral types earlier than F5. In the present paper new CCD photometric light curves in B, V, and R bands of BO CVn and the first complete light curve in V band of SS Com are presented.
- ID:
- ivo://CDS.VizieR/J/AJ/153/231
- Title:
- BVR photometry of EPIC 211957146
- Short Name:
- J/AJ/153/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the multi-band photometric and spectroscopic study of an over-contact binary system, EPIC211957146. The light curves exhibit a variable O' Connell effect, confirmed from our observational data and the Kepler K2 data. The best photometric solution incorporating a dark spot over the primary component unveils that the system has a low-mass ratio (q~0.17) and a high inclination (i~85{deg}). To confirm the solution and constrain the uncertainty, Monte-Carlo simulations are performed and the results are reported. Based on the O-C diagram analysis, we see that the variable shows a period increase at the rate of dP/dt~1.06x10^-6^days/yr, which is higher than the theoretically predicted value. Presence of a third body having a period of ~16.23years is evident from the O-C diagram. No filled-in effect is observed in the H{alpha} line, while the effect is vividly present in the Na line. From the Kepler K2 data, we found that the primary and secondary minima exhibit an anti-correlated O-C variation followed by an erratic behavior. This is possibly caused by the longitudinal motion of the spot, and hence, we set a lower limit of ~40days for the spot modulation. We also observe a possibly associated photometric difference in the primary depth by comparing our light curves with Kepler K2 normalized light curves. This system has a low-mass ratio and a high fill-out factor, and, theoretically, such a physical configuration would lead to a merger.
- ID:
- ivo://CDS.VizieR/J/AJ/151/124
- Title:
- BVR photometry of IZ Mon and AR Dra
- Short Name:
- J/AJ/151/124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multi-color photometric observations for two neglected near-contact binaries, IZ Mon (P=0.77980^d^) and AR Dra (P=0.67584^d^). By the aid of the updated W-D analysis code, the photometric solutions were deduced from the multi-color light curves (LCs). IZ Mon is a semi-detached binary with a mass ratio of q=0.388(+/-0.002) , while AR Dra is a detached star with a mass ratio of q=0.652(+/-0.002). The asymmetric LCs of IZ Mon were modeled by a hot spot on the secondary's surface, which may be attributed to mass transfer from the primary. Based on all collected eclipse times for two systems, we constructed their timing residual curves. The orbital period for IZ Mon may be continuously decreasing at a rate of dP/dt=-2.06(+/-0.04)days/yr, which may result from mass and angular momentum loss from the central system. For AR Dra, there exists a cyclic variation with a period of P_3_=104.9(+/-2.9)yr due to light-time orbit effect via the presence of the third body, whose mass is more than 0.28(+/-0.02)M_{Sun}_. Finally, two near-contact binaries, IZ Mon and AR Dra, will evolve into contact binaries.
- ID:
- ivo://CDS.VizieR/J/A+A/422/407
- Title:
- BVR photometry of MS0302+17
- Short Name:
- J/A+A/422/407
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the supercluster MS0302+17 (ClG 0302+17, z~0.42) using weak lensing analysis and deep wide field BVR photometry with the CFH12K camera. Using (B-V) vs (V-R) evolution tracks we identify early-type members of the supercluster, and foreground ellipticals. We derive a R band catalogue of background galaxies for weak lensing analysis. We compute the correlation functions of light and mass and their cross-correlation and test if light traces mass on supercluster, cluster and galaxy scales. We show that the data are consistent with this assertion. The {zeta}-statistic applied in regions close to cluster centers and global correlation analyses over the whole field converge toward the simple relation M/L=300+/-30M_{sun}_/L_{sun}_ in the B band. This independently confirms the earlier results obtained by Kaiser (1998ApJ...498...26K). If we model dark matter halos around each early-type galaxy by a truncated isothermal sphere, we find that a linear relation M{prop.to}L still holds. In this case, the average halo truncation radius is s_*_<~200(h_70_)^-1^kpc close to clusters cores whereas it reaches a lower limit of ~300(h_70_)^-1^kpc at the periphery. This change of s_*_ as a function of radial distance may be interpreted as a result of tidal stripping of early type galaxies. Nevertheless the lack of information on the spatial distribution of late-type galaxies affects such conclusions concerning variations of s_*_. Though all the data at hand are clearly consistent with the assumption that mass is faithfully traced by light from early-type galaxies, we are not able to describe in detail the contribution of late type galaxies. We however found it to be small. Forthcoming wide surveys in UV, visible, and near infrared wavelengths will provide large enough samples to extend this analysis to late-type galaxies using photometric redshifts.
- ID:
- ivo://CDS.VizieR/J/AJ/132/1593
- Title:
- BVR photometry of NGC 4594 globular clusters
- Short Name:
- J/AJ/132/1593
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A detailed imaging analysis of the globular cluster (GC) system of the Sombrero galaxy (NGC 4594) has been accomplished using a six-image mosaic from the Hubble Space Telescope Advanced Camera for Surveys. The quality of the data is such that contamination by foreground stars and background galaxies is negligible for all but the faintest 5% of the GC luminosity function. This enables the study of an effectively pure sample of 659 GCs until ~2mag fainter than the turnover magnitude, which occurs at M^TOM^_V_=-7.60+/-0.06 for an assumed m-M=29.77. Two GC metallicity subpopulations are easily distinguishable, with the metal-poor subpopulation exhibiting a smaller intrinsic dispersion in color compared to the metal-rich subpopulation.
- ID:
- ivo://CDS.VizieR/J/AJ/143/108
- Title:
- B'V'R' photometry of the BL Lac object S5 0716+714
- Short Name:
- J/AJ/143/108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our optical monitoring of the BL Lac object S5 0716+714 over seven nights in 2006 December. The monitoring was carried out simultaneously at three optical wavelengths with a novel photometric system. The object did not show large-amplitude internight variations during this period. Intranight variations were observed on four nights and probably on one more. Strong bluer-when-brighter chromatism was detected on both intranight and internight timescales. The intranight variation amplitude decreases in the wavelength sequence of B', R', and V'. Cross-correlation analyses revealed that the variability at the B' and V' bands leads that at the R' band by about 30 minutes on one night.
- ID:
- ivo://CDS.VizieR/J/PASP/121/699
- Title:
- BVR photometry of V343 Ori
- Short Name:
- J/PASP/121/699
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- BVR light curves of V343 Orionis were observed with the 85cm telescope at Xinglong Station of the National Astronomical Observatories of the Chinese Academy of Sciences, in 2007 and 2008. Using the Wilson-Devinney program, the photometric solution of V343 Ori was first deduced from those observations. Photometric results indicated that V343 Ori is an A-subtype W Ursae Majoris binary, whose mass ratio and overcontact degree are q=0.253(+/-0.004) and f=86.9%(+/-2.1%), respectively.
