- ID:
- ivo://CDS.VizieR/J/MNRAS/381/L84
- Title:
- CT1 photometry of 3 SMC old clusters
- Short Name:
- J/MNRAS/381/L84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results on the age and metallicity estimates of the Small Magellanic Cloud (SMC) clusters L 110, L 112 and L 113 obtained from CCD Washington CT_1_ photometry. We confirm L 113 as a relatively old and metal-poor cluster, and report for the first time that L 110 and 112 are also relatively old clusters (t~6.5Gyr) . Their derived ages and metallicities reinforce previous suggestions that the farther a cluster is from the centre of the galaxy, the older and more metal-poor it is, with some dispersion. In addition, the bursting star formation model still appears to be the most probable paradigm to describe the SMC's star formation history. We call attention to a second possible burst at ~6-7Gyr, besides the known burst at ~3Gyr.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/382/1203
- Title:
- CT1 photometry of 5 SMC star clusters
- Short Name:
- J/MNRAS/382/1203
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Colour-magnitude diagrams in the Washington system are presented for the first time for five star clusters projected on to the outer region of the Small Magellanic Cloud (SMC). The clusters are found to have ages in the range 0.1-1.0Gyr, as derived from the fit of isochrones with Z=0.004. This sample increases substantially the number of young clusters in the outer SMC - particularly in the south-east quadrant - with well-derived parameters. We combine our results with those for other clusters in the literature to derive as large and homogeneous a data base as possible (totalling 49 clusters) in order to study global effects.
- ID:
- ivo://CDS.VizieR/J/MNRAS/389/429
- Title:
- CT1 photometry of 7 young SMC star clusters
- Short Name:
- J/MNRAS/389/429
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD photometry in the Washington system C and T1 passbands down to T1~22 in the fields of L35, L45, L49, L50, L62, L63 and L85, seven poorly studied star clusters in the inner region of the Small Magellanic Cloud (SMC). We measured T1 magnitudes and C-T1 colours for a total of 114826 stars distributed throughout cluster areas of 13.7x13.7arcmin^2^ each. Cluster radii were estimated from star counts distributed throughout the entire observed fields.
- ID:
- ivo://CDS.VizieR/J/A+A/570/A53
- Title:
- CTS C30.10 SALT long-slit spectra
- Short Name:
- J/A+A/570/A53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Quasars can be used as a complementary tool to SN Ia to probe the distribution of dark energy in the Universe by measuring the time delay of the emission line with respect to the continuum. The understanding of the MgII emission line structure is important for cosmological application and for the black hole mass measurements of intermediate redshift quasars. Knowing the shape of MgII line and its variability allows for identification which part of the line should be used to measure the time delay and the black hole mass. We thus aim at determining the structure and the variability of the MgII line, as well as the underlying FeII pseudo-continuum. We performed five spectroscopic observations of a quasar CTS C30.10 (z=0.9000) with the SALT telescope between December 2012 and March 2014, and we studied the variations in the spectral shape in the 2700{AA}-2900{AA} rest frame. We show that the MgII line in this source consists of two kinematic components, which makes the source representative of type B quasars. Both components were modeled well with a Lorentzian shape, and they vary in a similar way. The FeII contribution seems to be related only to the first (blue) MgII component. Broad band spectral fitting instead favor the use of the whole line profile. The contribution of the narrow line region to MgII is very low, below 2%. The MgII variability is lower than the variability of the continuum, which is consistent with the simple reprocessing scenario. The variability level of CTS C30.10 and the measurement accuracy of the line and continuum is high enough to expect that further monitoring will allow the time delay between the MgII line and continuum to be measured.
- ID:
- ivo://CDS.VizieR/J/MNRAS/417/1559
- Title:
- CT1T2 photometry in 14 SMC star clusters
- Short Name:
- J/MNRAS/417/1559
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD photometry in the Washington system C, T1 and T2 passbands down to T1~23 in the fields of L3, L28, HW 66, L100, HW 79, IC 1708, L106, L108, L109, NGC 643, L112, HW 84, HW 85 and HW 86, 14 Small Magellanic Cloud (SMC) clusters, most of them poorly studied objects. We measured T1 magnitudes and C-T1 and T1-T2 colours for a total of 213 516 stars spread throughout cluster areas of 14.7x14.7arcmin^2^ each. We carried out an in-depth analysis of the field star contamination of the colour-magnitude diagrams (CMDs) and statistically cleaned the cluster CMDs.
- ID:
- ivo://CDS.VizieR/J/A+A/540/A58
- Title:
- CT1T2 photometry of 26 LMC cluster
- Short Name:
- J/A+A/540/A58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With the aim of enlarging the number of studied LMC clusters in the age range 8.0~<log(t)~<9.0, we focus here on a sample of mostly unstudied cluster candidates. We present, for the first time, CCD Washington CT1T2 photometry of stars in the field of 26 LMC clusters. The studied clusters turned out to be small angular size objects with ages within the age range 8.0~<log(t)~< 9.0, which are projected or immersed in dense star fields.
- ID:
- ivo://CDS.VizieR/J/AJ/134/229
- Title:
- CT1T2 Photometry of red giants in 2 globulars
- Short Name:
- J/AJ/134/229
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Washington photometry of the giant branches of the relatively metal-rich globular cluster NGC 6388 and compare it with 47 Tuc. By examining the spatial distribution of stellar colors across the red giant branch and using spectroscopic data on several bright giants, we found that NGC 6388's center is affected by differential reddening of at least {DELTA}E(B-V)~0.1. Most of the width of the red giant branch is caused by that differential reddening. The southeastern outer regions of the cluster seem to be less affected by variable dust extinction, and we find that NGC 6388 is slightly more metal-rich than 47 Tuc, with a distinct asymptotic giant branch. We have put an upper limit on possible variations in [Fe/H] for NGC 6388, finding that it must be less than ~0.2dex. It is unlikely that such a small range in metallicity could be responsible for the blue horizontal branch and blue tail stars in a cluster with a metallicity similar to the more massive 47 Tuc, which only exhibits a red horizontal branch.
- ID:
- ivo://CDS.VizieR/J/ApJ/662/808
- Title:
- Cusp radius in luminous elliptical galaxies
- Short Name:
- J/ApJ/662/808
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Black hole (BH) masses predicted from the M_BH_-sigma relationship conflict with predictions from the M_BH_-L relationship for high-luminosity galaxies, such as brightest cluster galaxies (BCGs). The M_BH_-L relationship predicts that some BCGs may harbor BHs with M_BH_ approaching 10^10^M_{sun}_ while the M_BH_-sigma relationship always predicts M_BH_<3x10^9^M_{sun}_. We argue that the M_BH_-L relationship is a plausible description for galaxies of high luminosity. If the cores in central stellar density are formed by binary BHs, the inner core cusp radius, r{gamma}, may be an independent witness of M_BH_. Using central structural parameters derived from a large sample of early-type galaxies observed by HST, we argue that L is superior to sigma as an indicator of r{gamma}.
- ID:
- ivo://CDS.VizieR/J/MNRAS/431/2106
- Title:
- CU Vir Stroemgren differential photometry
- Short Name:
- J/MNRAS/431/2106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In order to measure the variations of the magnetic chemically peculiar star CU Vir, we obtained 2821 good Stroemgren uvby photometric values from the Four College Automated Photometric Telescope in the period 1998-2012 and 5529 values from the Solar Mass Ejection Imager in the period 2003-2006, allowing us to further clarify the situation concerning its rotational period, described previously by Pyper et al. (1998A&A...339..822P). Our main result is that the O-C data since 1993 are consistent with a constant period of 0.5207137+/-0.0000010d, which is longer than the period 0.52070308d of Pyper et al. (1998A&A...339..822P). The data during the time period 1993-2012 show no evidence of glitches. The data between 1987 and 1993 correspond to a shorter period of 0.520701d, and the inclusion of those data in the previous study made the published period come out shorter. We also cannot rule out a constantly lengthening period if the data since 1987 are included; however, the fit is slightly better for a constant period. At least five more years of consistent data will be required to distinguish between these two models. Radio astronomy data published since 1998 show phase shifts in the radio emission peaks that are inconsistent with the rotation period inferred from the optical photometry. These shifts may be due to instabilities in the region where the radio emissions originate; they indicate that the photosphere and the upper atmosphere are not rigidly coupled.
- ID:
- ivo://CDS.VizieR/J/MNRAS/359/930
- Title:
- CUYS survey of Ha+NII ELG galaxies
- Short Name:
- J/MNRAS/359/930
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the CIDAUCMYale (Centro de Investigaciones de Astronomia, Universidad Complutense de Madrid, and Yale University) Survey (CUYS) for H{alpha}+[NII] 6549, 6584{AA} emission-line galaxies (ELGs) using objective-prism spectra. The most important properties of a catalogue with 427 entries and significant subsets are analysed. The complete sample contains 183 statistically confirmed ELGs in a sky area of 151deg^2^ and redshift up to 0.14. We determine the parameters of the H{alpha} luminosity function using the H{alpha}+[NII] flux directly measured on the ELG spectra in this sample, and the star formation rate density derived is in agreement with values reported in the literature.