- ID:
- ivo://CDS.VizieR/J/ApJ/712/L21
- Title:
- Calcium abundances in 17 globular clusters
- Short Name:
- J/ApJ/712/L21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use abundances of Ca, O, Na, and Al from high-resolution UVES spectra of 200 red giants in 17 globular clusters (GCs) to investigate the correlation found by Lee et al. (2009Icar..199..413C) between chemical enrichment from SNII and star-to-star variations in light elements in GC stars. We find that (1) the [Ca/H] variations between first and second generation stars are tiny in most GCs (~0.02-0.03dex, comparable with typical observational errors). In addition, (2) using a large sample of red giants in M4 (NGC 6121) with abundances from UVES spectra from Marino et al. (2008, Cat. J/A+A/490/625), we find that Ca and Fe abundances in the two populations of Na-poor and Na-rich stars are identical.
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- ID:
- ivo://CDS.VizieR/J/ApJ/750/140
- Title:
- Candidate globular clusters in NGC 1316
- Short Name:
- J/ApJ/750/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study mass functions of globular clusters derived from Hubble Space Telescope/Advanced Camera for Surveys images of the early-type merger remnant galaxy NGC 1316, which hosts a significant population of metal-rich globular clusters of intermediate age (~3Gyr). For the old, metal-poor ("blue") clusters, the peak mass of the mass function M_p_ increases with internal half-mass density {rho}_h_ as M_p_{prop.to}{rho}_h_^0.44^, whereas it stays approximately constant with galactocentric distance R_gal_. The mass functions of these clusters are consistent with a simple scenario in which they formed with a Schechter initial mass function and evolved subsequently by internal two-body relaxation. For the intermediate-age population of metal-rich ("red") clusters, the faint end of the previously reported power-law luminosity function of the clusters with R_gal_>9kpc is due to many of those clusters having radii larger than the theoretical maximum value imposed by the tidal field of NGC 1316 at their R_gal_. This renders disruption by two-body relaxation ineffective. Only a few such diffuse clusters are found in the inner regions of NGC 1316. Completeness tests indicate that this is a physical effect. Using comparisons with star clusters in other galaxies and cluster disruption calculations using published models, we hypothesize that most red clusters in the low-{rho}_h_ tail of the initial distribution have already been destroyed in the inner regions of NGC 1316 by tidal shocking, and that several remaining low-{rho}_h_ clusters will evolve dynamically to become similar to "faint fuzzies" that exist in several lenticular galaxies. Finally, we discuss the nature of diffuse red clusters in early-type galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/403/429
- Title:
- Candidate globular clusters in NGC 5170
- Short Name:
- J/MNRAS/403/429
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Here, we present Hubble Space Telescope/Advanced Camera for Surveys (ACS) imaging, in the B and I bands, of the edge-on Sb/Sc galaxy NGC 5170. Excluding the central disc region, we detect 142 objects with colours and sizes typical of globular clusters (GCs). Our main result is the discovery of a "blue tilt" (a mass-metallicity relation), at the 3{sigma} level, in the metal-poor GC subpopulation of this Milky Way like galaxy.
- ID:
- ivo://CDS.VizieR/J/AJ/130/1177
- Title:
- C and N abundances for M15 stars
- Short Name:
- J/AJ/130/1177
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of a large sample of moderate-resolution Keck Low Resolution Imaging Spectrometer spectra of subgiants and stars at the base of the red giant branch (RGB) in the Galactic globular cluster (GC) M15 (NGC 7078), most within the range 16.5<V<19.5 (1.2<M_V_<4.2), with the goal of deriving C abundances (from the G band of CH) and N abundances (from the NH band at 3360{AA}).
- ID:
- ivo://CDS.VizieR/J/AJ/145/43
- Title:
- CASE. V. Three eclipsing binaries in M4
- Short Name:
- J/AJ/145/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use photometric and spectroscopic observations of the eclipsing binaries V65, V66, and V69 in the field of the globular cluster M4 to derive masses, radii, and luminosities of their components. The orbital periods of these systems are 2.29, 8.11, and 48.19days, respectively. The measured masses of the primary and secondary components (M_p_ and M_s_) are 0.8035+/-0.0086 and 0.6050+/-0.0044M_{sun}_ for V65, 0.7842+/-0.0045 and 0.7443+/-0.0042M_{sun}_ for V66, and 0.7665+/-0.0053 and 0.7278+/-0/0048M_{sun}_ for V69. The measured radii (R_p_ and R_s_) are 1.147+/-0.010 and 0.6110 +/- 0.0092R_{sun}_ for V66, 0.9347+/-0.0048 and 0.8298+/-0.0053R_{sun}_ for V66, and 0.8655+/-0.0097 and 0.8074+/-0.0080R_{sun}_ for V69. The orbits of V65 and V66 are circular, whereas that of V69 has an eccentricity of 0.38. Based on systemic velocities and relative proper motions, we show that all three systems are members of the cluster. We find that the distance to M4 is 1.82+/-0.04kpc-in good agreement with recent estimates based on entirely different methods. We compare the absolute parameters of V66 and V69 with two sets of theoretical isochrones in mass-radius and mass-luminosity diagrams, and for assumed [Fe/H]=-1.20, [{alpha}/Fe]=0.4, and Y=0.25 we find the most probable age of M4 to be between 11.2 and 11.3Gyr. Color-magnitude diagram (CMD) fitting with the same parameters yields an age close to, or slightly in excess of, 12Gyr. However, considering the sources of uncertainty involved in CMD fitting, these two methods of age determination are not discrepant. Age and distance determinations can be further improved when infrared eclipse photometry is obtained.
- ID:
- ivo://CDS.VizieR/I/278
- Title:
- Catalog of stars in M3
- Short Name:
- I/278
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Catalog of 1571 stars contained in the globular cluster Messier 3, observed in 1905 at the Observatoire de Paris.
- ID:
- ivo://CDS.VizieR/III/244
- Title:
- Catalog of Stellar Rotational Velocities
- Short Name:
- III/244
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a compilation of the observed projected rotational velocities, V_rot_*sin(i), for 28179 stars from 166 open clusters, globular clusters and associations. The catalog.dat file contains 39351 individual V_rot_*sin(i) data, together with the error and the method of determination. Because of the possible confusion with the use of different names for stars belonging to clusters we have included alternative names using SIMBAD nomenclature. Rotational velocities from CDS catalogue III/226 (Glebocki+ 2000) are included. Information about the number of stars in each cluster as well as other cluster names can be found in the "clusters.dat" file. The bibliographical references are provided in the "refs.dat" file. The file "mean.dat" contains mean V*sin(i) values for each star. The individual v*sin(i) measurements were reduced to a uniform standard (to remove the systematic errors) and a weighted average of V*sin(i) was calculated. The V*sin(i) values used as standards are presented in the "standards.dat" file.
- ID:
- ivo://CDS.VizieR/II/117
- Title:
- Catalog of UBVRI Photometry of Globular Clusters
- Short Name:
- II/117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric data directly obtained in UBVRI or converted to UBVRI magnitudes are tabulated. The data comprise approximately 4600 records from 56 individuals and contains data unpublished at the time of the compilation as well as published data.
- ID:
- ivo://CDS.VizieR/J/ApJS/181/605
- Title:
- Catalog of X-ray sources in NGC 4278
- Short Name:
- J/ApJS/181/605
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the properties of the discrete X-ray sources detected in our monitoring program of the globular cluster (GC) rich elliptical galaxy, NGC 4278, observed with Chandra ACIS-S in six separate pointings, resulting in a co-added exposure of 458ks. From this deep observation, 236 sources have been detected within the region overlapped by all observations, 180 of which lie within the D25 ellipse of the galaxy. These 236 sources range in L_X_ from 3.5x10^36^erg/s (with 3{sigma} upper limit <=1x10^37^erg/s) to ~2x10^40^erg/s, including the central nuclear source which has been classified as a LINER. From optical data, 39 X-ray sources have been determined to be coincident with a GC, these sources tend to have high X-ray luminosity, with 10 of these sources exhibiting L_X_>1x10^38^erg/s. From X-ray source photometry, it has been determined that the majority of the 236 point sources that have well-constrained colors have values that are consistent with typical low-mass X-ray binary spectra, with 29 of these sources expected to be background objects from the log N-log S relation. There are 103 sources in this population that exhibit long-term variability, indicating that they are accreting compact objects. Three of these sources have been identified as transient candidates, with a further three possible transients. Spectral variations have also been identified in the majority of the source population, where a diverse range of variability has been identified, indicating that there are many different source classes located within this galaxy.
- ID:
- ivo://CDS.VizieR/J/A+A/483/183
- Title:
- Catalogue of Blue Stragglers
- Short Name:
- J/A+A/483/183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Blue Stragglers (BSS) Catalogues extracted from the photometric data base of 74 Galactic GCs published by Piotto et al., 2002, Cat. <J/A+A/391/945>. All the clusters were observed in the F439W and F555W photometric bands pointing the HST/WFPC2 camera to the central core. Candidates were selected according to their position in the colour magnitude diagrams. A detailed description of the selection process is given in the paper. We give for each cluster a list of blue straggler candidates together with their photometric data.
