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2381. CCD photometry of star clusters in the LMC
ID:
ivo://CDS.VizieR/J/MNRAS/450/2122
Title:
CCD photometry of star clusters in the LMC
Short Name:
J/MNRAS/450/2122
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Washington system colour-magnitude diagrams (CMDs) for 17 practically unstudied star clusters located in the bar as well as in the inner disc and outer regions of the Large Magellanic Cloud (LMC). Cluster sizes were estimated from star counts distributed throughout the entire observed fields. Based on the best fits of theoretical isochrones to the cleaned (C-T_1_, T_1_) CMDs, as well as on the {delta}T_1_ parameter and the standard giant branch method, we derive ages and metallicities for the cluster sample. Four objects are found to be intermediate-age clusters (1.8-2.5 Gyr), with [Fe/H] ranging from -0.66 to -0.84. With the exception of SL 263, a very young cluster (~16 Myr), the remaining 12 objects are aged between 0.32 and 0.89 Gyr, with their [Fe/H] values ranging from -0.19 to -0.50. We combined our results with those for other 231 clusters studied in a similar way using the Washington system. The resulting age-metallicity relationship shows a significant dispersion in metallicities, whatever age is considered. Although there seems to exist a clear tendency for the younger clusters to be more metal rich than the intermediate ones, we believe that none of the chemical evolution models currently available in the literature reasonably well represents the recent chemical enrichment processes in the LMC clusters. The present sample of 17 clusters is part of our ongoing project of generating a data base of LMC clusters homogeneously studied using the Washington photometric system and applying the same analysis procedure.
2382. CCD photometry of variable stars in M9
ID:
ivo://CDS.VizieR/J/AJ/112/618
Title:
CCD photometry of variable stars in M9
Short Name:
J/AJ/112/618
Date:
21 Oct 2021
Publisher:
CDS
Description:
CCD observations have been used to derive precise light curves for six of the previously known RR Lyrae variables in the Oosterhoff type II globular cluster M9 and to search for additional variables. Nine variables have been discovered, eight of the RR Lyrae type. As a result, the total number of RR Lyrae variables has been revised from 9 to 17 (9 RRc and 8 RRab), the mean period of the RRc stars has been revised from 0.341d to 0.342d and that of the RRab stars from 0.621d to 0.638d. Simon's method that relates physical properties of RRc stars to the pulsation period and Fourier phase parameter {phi}_31_ has been used to determine the mass, luminosity, and temperature for one of the RRc stars. Published observations of RR Lyrae stars in M15 have been used to test Simon's method (1993ApJ...410..526S, 1993, IAUCo, 139, 315) and the results are promising. The formulae of Jurcsik and Kovacs (1996A&A...312..111J) for relating Fourier parameters of RRab stars to [Fe/H] have been used to derive a metal abundance for M9.
2383. CCD photometry & velocities of NGC 3680 stars
ID:
ivo://CDS.VizieR/J/A+AS/118/407
Title:
CCD photometry & velocities of NGC 3680 stars
Short Name:
J/A+AS/118/407
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new CCD photometry in the b and y colours of the Stroemgren uvby system for 310 stars in a 13'x13' field centered on the intermediate-age open cluster NGC 3680. Careful cross-checks indicate that previously published BV photometry of NGC 3680 is affected by random and/or systematic errors precluding its use in critical comparison with theoretical isochrone computations. Detailed notes on several individual stars are given. In addition, we present =~400 new photoelectric radial-velocity observations of 109 stars obtained with the CORAVEL scanner during the period 1988-1994. These data allow substantially complete identification of member and non-member stars in the field, and of spectroscopic binaries in both groups. Rotational velocities have also been derived for the programme stars, and our velocity variability criteria for stars of all rotations are described. The further astrophysical discussion of the data, including the definition of radial-velocity membership criteria, theoretical isochrone fitting, and the dynamical state of the cluster and the origin of its "bimodal turnoff", will appear in a separate paper (Nordstroem et al. 1996).
2384. CCD positions for eight Jovian irregular satellites
ID:
ivo://CDS.VizieR/J/A+A/453/349
Title:
CCD positions for eight Jovian irregular satellites
Short Name:
J/A+A/453/349
Date:
21 Oct 2021
Publisher:
CDS
Description:
The astrometric positions of eight irregular Jovian satellites are given for the oppositions of the planet from 1995 to 1999. These positions were measured on 204 CCD frames obtained at the Cassegrain focus of a 1.6m reflector. They are compared with the theoretically calculated positions from JPL Development Ephemeris. The observed minus-calculated standard deviation for all observations of the eight satellites are {sigma}_RA_=0.071" and {sigma}_DE_=0.052". The USNO-A2.0 (<I/252>) catalog was used for the astrometric calibration.
2385. CCD R photometry in the UMa supercluster
ID:
ivo://CDS.VizieR/J/PAZh/27/403
Title:
CCD R photometry in the UMa supercluster
Short Name:
J/PAZh/27/403
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric parameters for 98 early-type galaxies in the central for 11 clusters, belonging to the Ursa Major supercluster, are presented. Galaxies in the following clusters have been observed: A1270, A1291, A1377, A1318, A1383, A1436, Anon1, Anon2, Anon3, Anon4, Sh166. The derivation of the effective parameters takes the seeing into account.
2386. CCD R photometry of 17 clusters of galaxies
ID:
ivo://CDS.VizieR/J/A+A/382/389
Title:
CCD R photometry of 17 clusters of galaxies
Short Name:
J/A+A/382/389
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a study of streaming motion of galaxy clusters around the Giant Void (RA~13h, DE~40{deg}, z~0.11 and a diameter of 150/hMpc) in the distribution of rich Abell clusters. We used the Kormendy relation as a distance indicator taking into account galaxy luminosities. Observations were carried out in Kron-Cousins R_c_ system on the 6m and 1m telescopes of SAO RAS. For 17 clusters in a spherical shell of 25/hMpc in thickness centered on the void no significant diverging motion (expected to be generated by the mass deficit in the void) has been detected. This implies that cosmological models with low {Omega}_m_ are preferred. To explain small mass underdensity inside the Giant Void, a mechanism of void formation with strong biasing is required.
2387. CCD R Photometry of WHISP Dwarf Galaxies
ID:
ivo://CDS.VizieR/J/A+A/390/863
Title:
CCD R Photometry of WHISP Dwarf Galaxies
Short Name:
J/A+A/390/863
Date:
21 Oct 2021
Publisher:
CDS
Description:
R-band surface photometry is presented for 171 late-type dwarf and irregular galaxies. For a subsample of 46 galaxies B-band photometry is presented as well. We present surface brightness profiles as well as isophotal and photometric parameters including magnitudes, diameters and central surface brightnesses. Absolute photometry is accurate to 0.1 mag or better for 77% of the sample. For over 85% of the galaxies the radial surface brightness profiles are consistent with published data within the measured photometric uncertainty. For most of the galaxies in the sample HI data have been obtained with the Westerbork Synthesis Radio Telescope. The galaxies in our sample are part of the WHISP project (Westerbork HI Survey of Spiral and Irregular Galaxies), which aims at mapping about 500 nearby spiral and irregular galaxies in HI. The availability of HI data makes this data set useful for a wide range of studies of the structure, dark matter content and kinematics of late-type dwarf galaxies.
2388. CCD search for Cepheids in Crux and Centaurus
ID:
ivo://CDS.VizieR/II/162
Title:
CCD search for Cepheids in Crux and Centaurus
Short Name:
II/162
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains the results of a photometric survey for variable stars in a 9.4 square degree region along the galactic plane in Crux and Centaurus. A total of 300308 stars were observed at seven epochs over 42 days; 224 524 of these stars were detected at multiple epochs and were tested for possible variations in brightness that exceed observational error. 2422 stars are identified as variable at a formal confidence level of 99%; 270 of the new variables brighter than I=14.0 are classified as long period variables. A list of 242 likely short period variables with RMS amplitudes >=0.060mag is given. From this list, 37 Cepheid candidates were selected after inspection of their light curves.
2389. CCD search for Cepheids in Crux and Centaurus
ID:
ivo://CDS.VizieR/J/AJ/101/1763
Title:
CCD search for Cepheids in Crux and Centaurus
Short Name:
II/162
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains the results of a photometric survey for variable stars in a 9.4 square degree region along the galactic plane in Crux and Centaurus. A total of 300308 stars were observed at seven epochs over 42 days; 224 524 of these stars were detected at multiple epochs and were tested for possible variations in brightness that exceed observational error. 2422 stars are identified as variable at a formal confidence level of 99%; 270 of the new variables brighter than I=14.0 are classified as long period variables. A list of 242 likely short period variables with RMS amplitudes &#8805;0.060mag is given. From this list, 37 Cepheid candidates were selected after inspection of their light curves.
2390. CCD speckle obs. of binary stars. II.
ID:
ivo://CDS.VizieR/J/AJ/120/2638
Title:
CCD speckle obs. of binary stars. II.
Short Name:
J/AJ/120/2638
Date:
21 Oct 2021
Publisher:
CDS
Description:
Speckle observations of 145 double stars and suspected double stars are presented and discussed. On the basis of multiple observations, a total of 280 position angle and separation measures are determined, as well as 23 high-quality nondetections. All observations were taken with the (unintensified) Rochester Institute of Technology fast-readout CCD camera mounted on the Lowell-Tololo 61 cm telescope at the Cerro Tololo Inter-American Observatory during 1999 October. We find that the measures, when judged as a whole against ephemeris positions of binaries with very well-known orbits, have root mean square deviations of 18+/-03{deg} in position angle and 13+/-2mas in separation. Eleven double stars discovered by Hipparcos were also successfully observed, and the change in position angle and/or separation since the Hipparcos observations was substantial in three cases.

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