- ID:
- ivo://CDS.VizieR/J/ApJ/559/812
- Title:
- Globular cluster system in M87
- Short Name:
- J/ApJ/559/812
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive database of kinematic, photometric, and positional information for 352 objects in the field of M87 (NGC 4486), the central giant elliptical galaxy in the Virgo Cluster; the majority of the tracers are globular clusters associated with that galaxy. New kinematic information comes from multislit observations with the Multi-Object Spectrograph (MOS) of the Canada-France-Hawaii Telescope (CFHT), an investigation that has added 96 new velocities to and confirmed many of the earlier values in a preexisting data set of 256 velocities published elsewhere. The photometry, consisting of magnitudes and colors in the Washington (T_1_, C-T_1_) system, is based on CCD observations made at the Cerro Tololo Inter-American Observatory (CTIO) and the Kitt Peak National Observatory (KPNO).
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Search Results
- ID:
- ivo://CDS.VizieR/J/PASP/109/883
- Title:
- Globular metallicity scale. I.
- Short Name:
- J/PASP/109/883
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained 2640 CCD spectra with resolution ~4{AA} in the region 7250-9000{AA} for 976 stars lying near the red giant branches in color-magnitude diagrams of 52 Galactic globular clusters. Radial velocities of ~16km/s accuracy per star determined from the spectra are combined with other criteria to assess quantitative membership probabilities. Measurements of the equivalent widths of the infrared calcium triplet lines yield a relative metal-abundance ranking with a precision that compares favorably to other techniques. Regressions between our system and those of others are derived. Our reduction procedures are discussed in detail, and the resultant catalog of derived velocities and equivalent widths is presented. The metal abundances derived from these data will be the subject of a future paper. (c) Astronomical Society of the Pacific
1393. Globulars of M81
- ID:
- ivo://CDS.VizieR/J/AJ/109/1055
- Title:
- Globulars of M81
- Short Name:
- J/AJ/109/1055
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained photometric BVR, morphological, and astrometric information on 3774 objects located within a 25' radius of M81. This catalogue is complete for 15 <= V <= 21; it is used here to identify globular cluster candidates in M81 and as a database for a statistical analysis of the system as a whole. The M81 globular cluster system is revealed as a strong surface density excess of ~70 objects within an 11 kpc galactocentric radius. The total population is estimated at N_T = 210 +/- 30 globulars. The spatial, (B-V), and (V-R) distributions are very similar to those of the Milky Way and of M31. Small but significant systematic errors in Madore et al.'s [AJ, 106, 2243 (1993)] photometry could be responsible for an overestimate of the Cepheid distance to M81 [(m-M)0 = 27.8] and we propose a revised modulus of (m-M)0 = 27.5 +/- 0.3. The globular cluster luminosity function then reaches its maximum at M_V* = -7.5 +/- 0.4, as it does in the galaxy and in M31. There is suggestive evidence that 13 +/- 5 objects are globulars seen through the disk of M81; spectroscopy or high-resolution imaging will resolve this issue. Using the (B-R)0 index to trace [Fe/H], we notice a weak dependence of mean metallicity on galactocentric distance, as observed in the galaxy and in M31. This result argues in favour of in situ globular formation during the continuous collapse and self-enrichment of an early-type spiral host.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/254
- Title:
- GMBCG galaxy cluster catalog from SDSS DR7
- Short Name:
- J/ApJS/191/254
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a large catalog of optically selected galaxy clusters from the application of a new Gaussian Mixture Brightest Cluster Galaxy (GMBCG) algorithm to SDSS Data Release 7 data. The algorithm detects clusters by identifying the red-sequence plus brightest cluster galaxy (BCG) feature, which is unique for galaxy clusters and does not exist among field galaxies. Red-sequence clustering in color space is detected using an Error Corrected Gaussian Mixture Model. We run GMBCG on 8240 deg^2^ of photometric data from SDSS DR7 to assemble the largest ever optical galaxy cluster catalog, consisting of over 55,000 rich clusters across the redshift range from 0.1<z<0.55. We present Monte Carlo tests of completeness and purity and perform cross-matching with X-ray clusters and with the maxBCG sample at low redshift. These tests indicate high completeness and purity across the full redshift range for clusters with 15 or more members.
- ID:
- ivo://CDS.VizieR/J/MNRAS/405/2243
- Title:
- GMOS/WIYN spectroscopic catalogue
- Short Name:
- J/MNRAS/405/2243
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the largest spectroscopic follow-up performed in SWIRE ELAIS-N1. We were able to determine redshifts for 289 extragalactic sources. The values of spectroscopic redshifts of the latter have been compared with the estimated values from our photometric redshift code with very good agreement between the two for both galaxies and quasars.
- ID:
- ivo://CDS.VizieR/J/A+A/655/A106
- Title:
- GO And, 84 UMa, kappa Psc ESPaDOnS spectra
- Short Name:
- J/A+A/655/A106
- Date:
- 11 Mar 2022 13:28:01
- Publisher:
- CDS
- Description:
- The aim of this work is to determine fundamental parameters of three Ap stars, GO And (HD 4778), {kappa} Psc (HD 220825), and 84 UMa (HD 120198), using spectroscopic techniques. By analysing these stars, we complete the sample of Ap stars for which fundamental parameters have additionally been derived by means of interferometry. This enables a cross-comparison of results derived by direct and indirect methods. Our study is based on the analysis of high-resolution spectra with a high signal-to-noise ratio that were obtained with ESPaDOnS spectrograph. We used an iterative method of fundamental parameter determinations that includes self-consistent modelling of the stellar atmosphere, taking individual abundances of chemical elements into account and subsequently fitting a theoretical spectral energy distribution to the observed distribution. The quality of the spectroscopic determinations was evaluated through a comparison with the interferometric results. For all investigated stars we determined fundamental parameters and derived chemical abundances that turn to be typical for Ap stars and are characterised mainly by gradual increase of heavy elements atmospheric abundance from an order of magnitude for iron peak elements up to very significant excesses of 3-4dex of the rare-earth elements relative to the solar values. The only exception is Ba which abundance is close to the solar one. There is also a significant He deficiency in the atmospheres of HD 120198 and HD 220825, whereas He abundance in HD 4778 is close to the solar one. We do not find significant Fe and Cr stratification. Using these abundances we constructed self-consistent atmospheric models for each star. The effect of the surface chemical inhomogeneity on the derived fundamental parameters did not exceed +/-100K in effective temperature which lies within a range of errors in similar self-consistent analyses of Ap stars. Finally, we compared spectroscopically derived effective temperatures, radii, and luminosity for 13 out of 14 Ap stars in benchmarking sample with the interferometric results. While radii and luminosity agree within the quoted errors of both determinations, spectroscopic effective temperatures are higher than the interferometric ones for stars with Teff>9000K. The observed hydrogen line profiles favour the spectroscopically derived temperatures.
- ID:
- ivo://CDS.VizieR/J/ApJ/859/33
- Title:
- GOBELINS. IV. VLBA obs. of Taurus
- Short Name:
- J/ApJ/859/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new trigonometric parallaxes and proper motions of young stellar objects in the Taurus molecular cloud complex from observations collected with the Very Long Baseline Array as part of the Gould's Belt Distances Survey. We detected 26 young stellar objects and derived trigonometric parallaxes for 18 stars with an accuracy of 0.3% to a few percent. We modeled the orbits of six binaries and determined the dynamical masses of the individual components in four of these systems (V1023 Tau, T Tau S, V807 Tau, and V1000 Tau). Our results are consistent with the first trigonometric parallaxes delivered by the Gaia satellite and reveal the existence of significant depth effects. We find that the central portion of the dark cloud Lynds 1495 is located at d=129.5+/-0.3pc, while the B216 clump in the filamentary structure connected to it is at d=158.1+/-1.2pc. The closest and remotest stars in our sample are located at d=126.6+/-1.7pc and d=162.7+/-0.8pc, yielding a distance difference of about 36pc. We also provide a new distance estimate for HL Tau that was recently imaged. Finally, we compute the spatial velocity of the stars with published radial velocity and investigate the kinematic properties of the various clouds and gas structures in this region.
- ID:
- ivo://CDS.VizieR/J/ApJ/865/73
- Title:
- GOBELINS. V. Kinematics of Perseus
- Short Name:
- J/ApJ/865/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We derive the distance and structure of the Perseus molecular cloud by combining trigonometric parallaxes from Very Long Baseline Array (VLBA) observations, taken as part of the GOBELINS survey and Gaia Data Release 2. Based on our VLBA astrometry, we obtain a distance of 321+/-10pc for IC 348. This is fully consistent with the mean distance of 320+/-26 measured by Gaia. The VLBA observations toward NGC 1333 are insufficient to claim a successful distance measurement to this cluster. Gaia parallaxes, on the other hand, yield a mean distance of 293+/-22pc. Hence, the distance along the line of sight between the eastern and western edges of the cloud is ~30pc, which is significantly smaller than previously inferred. We use Gaia proper motions and published radial velocities to derive the spatial velocities of a selected sample of stars. The average velocity vectors with respect to the LSR are (u,v,w)=(-6.1+/-1.6, 6.8+/-1.1, -0.9+/-1.2) and (-6.4+/-1.0, 2.1+/-1.4, -2.4+/-1.0)km/s for IC 348 and NGC 1333, respectively. Finally, our analysis of the kinematics of the stars has shown that there is no clear evidence of expansion, contraction, or rotational motions within the clusters.
1399. GO Cyg BV light curves
- ID:
- ivo://CDS.VizieR/J/other/NewA/17.296
- Title:
- GO Cyg BV light curves
- Short Name:
- J/other/NewA/17.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this study, we present long term photometric variations of the close binary system GO Cyg. Modelling of the system shows that the primary is filling Roche lobe and the secondary of the system is almost filling its Roche lobe. The physical parameters of the system are M_1_=3.0+/-0.2M_{sun}_, M_2_=1.3+/-0.1M_{sun}_, R_1_=2.50+/-0.12R_{sun}_, R_2_=1.75+/-0.09R_{sun}_, L_1_=64+/-9L_{sun}_, L_2_=4.9+/-0.7L_{sun}_, and a=5.5+/-0.3R_{sun}_. Our results show that GO Cyg is the most massive system near contact binary (NCB). Analysis of times of the minima shows a sinusoidal variation with a period of 92.3+/-0.5-years due to a third body whose mass is less than 2.3M_{sun}_. Finally a period variation rate of -1.4x10^-9^d/yr has been determined using all available light curves.
1400. GOODS initial results
- ID:
- ivo://CDS.VizieR/II/261
- Title:
- GOODS initial results
- Short Name:
- II/261
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present initial results from the Great Observatories Origins Deep Survey (GOODS) that are primarily, but not exclusively, based on multiband imaging data obtained with the Hubble Space Telescope and the Advanced Camera for Surveys (ACS). The survey covers roughly 320 arcmin2 in the ACS F435W, F606W, F814W, and F850LP bands, divided into two well-studied fields. Existing deep observations from the Chandra X-Ray Observatory and ground-based facilities are supplemented with new, deep imaging in the optical and near-infrared from the European Southern Observatory and from the Kitt Peak National Observatory. Deep observations with the Space Infrared Telescope Facility are scheduled. Reduced data from all facilities are being released worldwide within 36 months of acquisition. Together, this data set provides two deep reference fields for studies of distant normal and active galaxies, supernovae, and faint stars in our own Galaxy. This Letter serves to outline the survey strategy and describe the specific data that have been used in the accompanying letters, summarizing the reduction procedures and sensitivity limits.
