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17221. VR light curves of M2 variables
ID:
ivo://CDS.VizieR/J/MNRAS/372/69
Title:
VR light curves of M2 variables
Short Name:
J/MNRAS/372/69
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of CCD V and R photometry of the RR Lyrae stars in M2. The periodicities of most variables are revised and new ephemerides are calculated. Light-curve decomposition of the RR Lyrae stars was carried out and the corresponding mean physical parameters [Fe/H]=-1.47, Teff=6276K, logL=1.63L_{sun}_ and M_V_=0.71 from nine RRab and [Fe/H]=-1.61, M=0.54M_{sun}_, Teff=7215K, logL=1.74L_{sun}_ and M_V_=0.71 from two RRc stars were calculated. A comparison of the radii obtained from the above luminosity and temperature with predicted radii from non-linear convective models is discussed. The estimated mean distance to the cluster is 10.49+/-0.15kpc. These results place M2 correctly in the general globular cluster sequences for Oosterhoff type, mass, luminosity and temperature, all as a function of the metallicity. Mean relationships for M, logL/L_{sun}_, Teff and MV as a function of [Fe/H] for a family of globular clusters are offered. These trends are consistent with evolutionary and structural notions on the horizontal branch. Eight new variables are reported.
17222. VR light curves of 15 RR Lyrae in NGC 4147
ID:
ivo://CDS.VizieR/J/other/RMxAA/40.209
Title:
VR light curves of 15 RR Lyrae in NGC 4147
Short Name:
J/other/RMxAA/40
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of CCD V and R photometry of the RR Lyrae stars known in NGC 4147. The periodicities of most variables are revised and new ephemerides are calculated. The Blazhko effect has been detected in V2 and V6. Three previously reported variables; V5, V9, and V15 are found to be non-variable. A new variable V18 was discovered with a period of 0.49205-days and an amplitude of 0.15mag. Using the approach of Fourier decomposition of the light curves, the physical parameters of the RRab and RRc variables were estimated. The cluster is of the Oosterhoff type I. With the newly values [Fe/H]=-1.22+/-0.31 and 16.8+/-1.3kpc, the cluster fits very well into the Oosterhoff type-metallicity and metallicity-temperature sequence found in globular clusters. A comparison with ZAHB models indicates that the RRab stars have not yet evolved off the horizontal branch, a result consistent with the mean period of the RRab variables and with the metallicity of the cluster derived in this work.
17223. VRO 42.05.01 CO datacubes
ID:
ivo://CDS.VizieR/J/A+A/627/A75
Title:
VRO 42.05.01 CO datacubes
Short Name:
J/A+A/627/A75
Date:
21 Oct 2021
Publisher:
CDS
Description:
The environment of supernova remnants (SNRs) is a key factor in their evolution, particularly at later stages of their existence. Mixed-morphology (MM) SNRs have a peculiar centre-filled X-ray shape that remains enigmatic. It is often assumed that they evolve in very dense environments, and that the X-ray morphology is due to interactions between the SNRs and their surroundings. We aim to determine whether VRO 42.05.01 is embedded in, and interacting with, a dense molecular environment. We also aim to understand the multi-wavelength emission from the environment of this SNR, and whether the interstellar material can be responsible for the the MM nature of the source, and for its strange radio and optical shape. We used the IRAM telescope in Pico Veleta, Spain, to search for signs of interaction between the SNR and neighbouring molecular clouds. We observed a region of 260 140 towards the west of VRO 42.05.01 and a region of 80 40 towards the north of the remnant in the ^12^CO J=1-0, ^13^CO J=1-0, and ^12^CO J=2-1 transitions with the EMIR receiver. We made maps of the properties of the observed molecular clouds (peak temperatures, central velocities, velocity dispersions), as well as maps of column density along the line of sight, and ratio of the ^12^CO J=2-1 to ^12^CO J=1-0 transitions.We also analyse archival optical, infrared, and radio spectroscopic data for other hints on the nature of the medium. We do not find conclusive physical proof that the SNR is interacting with the few, clumpy molecular clouds that surround it in the region of our observations, although there is some suggestion of such interaction (in a region outside our map) from infrared emission. We find that there is a velocity gradient in one of the molecular clouds that is consistent with a stellar wind blown by a 12-14M_{sun}_ progenitor star.We reassess the literature distance to VRO 42.05.01, and propose that it has a local standard of rest velocity of ~6km/s, and that it is located 1.0+/-0.4kpc away (the earlier distance value was 4.5+/-1.5kpc).We find that a dust sheet intersects VRO 42.05.01 and is possibly related to its double shell-shaped morphology.
17224. VR photometry for 914 stars in NGC 188
ID:
ivo://CDS.VizieR/J/AJ/152/129
Title:
VR photometry for 914 stars in NGC 188
Short Name:
J/AJ/152/129
Date:
21 Oct 2021
Publisher:
CDS
Description:
We used the newly commissioned 50cm Binocular Network telescope at Qinghai Station of Purple Mountain Observatory (Chinese Academy of Sciences) to observe the old open cluster NGC188 in V and R as part of a search for variable objects. Our time-series data span a total of 36 days. Radial velocity and proper-motion selection resulted in a sample of 532 genuine cluster members. Isochrone fitting was applied to the cleaned cluster sequence, yielding a distance modulus of (m-M)_V_^0^=11.35+/-0.10mag and a total foreground reddening of E(V-R)=0.062+/-0.002mag. Light-curve solutions were obtained for eight W Ursae Majoris eclipsing binary systems (W UMas), and their orbital parameters were estimated. Using the latter parameters, we estimate a distance to the W UMas that is independent of the host cluster's physical properties. Based on combined fits to six of the W UMas (EP Cep, EQ Cep, ES Cep, V369 Cep, and-for the first time-V370 Cep and V782 Cep), we obtain an average distance modulus of (m-M)_V_^0^=11.31+/-0.08mag, which is comparable to that resulting from our isochrone fits. These six W UMas exhibit an obvious period-luminosity relation. We derive more accurate physical parameters for the W UMa systems and discuss their initial masses and ages. The former show that these W UMa systems have likely undergone angular momentum evolution within a convective envelope (W-type evolution). The ages of the W UMa systems agree well with the cluster's age.
17225. VR photometry of Century Survey galaxies
ID:
ivo://CDS.VizieR/J/AJ/122/714
Title:
VR photometry of Century Survey galaxies
Short Name:
J/AJ/122/714
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use 64{deg}^2^ of deep V and R CCD images to measure the local V- and R-band luminosity functions of galaxies. The V_0_<16.7 and R_0_<16.2 redshift samples contain 1255 and 1251 galaxies and are 98.1% and 98.2% complete, respectively.
17226. VR photometry of type II Cepheids
ID:
ivo://CDS.VizieR/J/AJ/128/1748
Title:
VR photometry of type II Cepheids
Short Name:
J/AJ/128/1748
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 1256 new photometric observations of 36 Cepheids with periods longer than 8 days. The majority are likely type II Cepheids, but we have included about a dozen classical Cepheids for comparison purposes, a few stars of uncertain type, and one putative RV Tauri star. We discuss the appearance of the light curves, the Fourier parameters, and the light-curve stability in terms of differentiation between type I and type II Cepheids. Although we encounter the same difficulties as previous investigators in using these parameters for this purpose, we are able to identify some stars of particular interest, including several likely type I Cepheids at large distances from the Galactic plane. Six stars with especially large period changes are identified and discussed.
17227. VR photometry of type II Cepheids. III
ID:
ivo://CDS.VizieR/J/AJ/130/832
Title:
VR photometry of type II Cepheids. III
Short Name:
J/AJ/130/832
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 741 new photometric observations for 22 Cepheids with periods between 3 and 8 days. Many of the stars are probable type II Cepheids, but we have included some type I Cepheids for comparison.
17228. vsini of B0-B3 stars in 7 young clusters
ID:
ivo://CDS.VizieR/J/AJ/133/1092
Title:
vsini of B0-B3 stars in 7 young clusters
Short Name:
J/AJ/133/1092
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a study aimed at assessing the differences in the distribution of rotation speeds N(vsini) among young (1-15Myr) B stars spanning a range of masses 6M_{sun}_<M<12M_{sun}_ and located in different environments: seven low-density ({rho}<1M_{sun}_/pc^3^) ensembles that are destined to become unbound stellar associations, and eight high-density ({rho}>>1M_{sun}_/pc^3^) ensembles that will survive as rich, bound stellar clusters for ages well in excess of 10^8^yr.
17229. vsini of binaries with evolved component
ID:
ivo://CDS.VizieR/J/ApJ/578/943
Title:
vsini of binaries with evolved component
Short Name:
J/ApJ/578/943
Date:
21 Oct 2021
Publisher:
CDS
Description:
In the present study we analyze the behavior of the rotational velocity, vsini, for a large sample of 134 spectroscopic binary systems with a giant star component of luminosity class III, along the spectral region from middle F to middle K.
17230. vsini of evolved metal-poor stars
ID:
ivo://CDS.VizieR/J/A+A/458/895
Title:
vsini of evolved metal-poor stars
Short Name:
J/A+A/458/895
Date:
21 Oct 2021
Publisher:
CDS
Description:
Precise rotational velocities vsini are presented for a large sample of 100 metal-poor stars, most of them evolving off the main-sequence. The survey was carried out with the FEROS and CORALIE spectrometers. For the vsini measurements, obtained from spectral synthesis, we estimate an uncertainty of about 2.0km/s. For the large majority of the stars composing the present sample rotational velocities have been measured for the first time.

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