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371. 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.
372. 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.
373. 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.
374. BVRi'z'JHKs photometry of ERO objects
ID:
ivo://CDS.VizieR/J/PASJ/55/1079
Title:
BVRi'z'JHKs photometry of ERO objects
Short Name:
J/PASJ/55/1079
Date:
21 Oct 2021
Publisher:
CDS
Description:
We studied the evolution of elliptical galaxies at z>~1 using a sample of 247 Extremely Red Objects (EROs) with R-Ks>3.35 (AB) and Ks<=22.1 (AB) constructed from BVRi'z'JHKs multicolor data of a 114arcmin^2^ area in the Subaru/XMM-Newton Deep Field taken with the Subaru Telescope and the UH 2.2m telescope. By fitting template spectra of old galaxies (OGs) and young, dusty starbursts (DSs) to the multicolor data, we classified EROs into these two classes and estimated their redshifts. We found that 58% of the EROs in our sample belong to the OG class and that these OGs have a wide range of colors at any redshift. We derived rest-frame B-band luminosity functions of OGs in our sample at z=1-1.5 and 1.5-2.5, and found that the number density of galaxies obeying passive evolution drops at z>~1.5 by a factor of three or more. The spatial correlation length of OGs is estimated to be r_0_>~8h^-1^Mpc, which is comparable to, or larger than, those of present-day early-type galaxies of similar luminosities. We also discussed properties of DSs in our data.
375. BVRJHKgr photometry of bright spiral galaxies
ID:
ivo://CDS.VizieR/J/ApJS/162/80
Title:
BVRJHKgr photometry of bright spiral galaxies
Short Name:
J/ApJS/162/80
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometrically calibrated images and surface photometry in the B, V, R, J, H, and K bands of 25, and in the g, r, and K bands of five nearby bright (B^0^_T_<12.5 mag) spiral galaxies with inclinations of 30{deg}-65{deg} spanning the Hubble sequence from Sa to Scd. Data are from The Ohio State University Bright Spiral Galaxy Survey (Eskridge et al., Cat. <J/ApJS/143/73>), the Two Micron All Sky Survey (2006AJ....131.1163S), and the Sloan Digital Sky Survey Second Data Release (Abazajian et al., 2004AJ....128..502A). Radial surface brightness profiles are extracted, and integrated magnitudes are measured from the profiles. Axis ratios, position angles, and scale lengths are measured from the near-infrared images. A one-dimensional bulge/disk decomposition is performed on the near-infrared images of galaxies with a nonnegligible bulge component, and an exponential disk is fit to the radial surface brightness profiles of the remaining galaxies.
376. BVR phot. of Basel 11b, King 14, Czernik 43
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.
377. BVR photometry in N214C
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.
378. BVR photometry of IZ Mon and AR Dra
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.
379. BVR photometry of MS0302+17
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.
380. BVR photometry of NGC 4594 globular clusters
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.