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291. CaII spectroscopy of SMC red giants
ID:
ivo://CDS.VizieR/J/AJ/138/517
Title:
CaII spectroscopy of SMC red giants
Short Name:
J/AJ/138/517
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained near-infrared spectra covering the CaII triplet lines for a large number of stars associated with 16 Small Magellanic Cloud (SMC) clusters using the VLT + FORS2. These data compose the largest available sample of SMC clusters with spectroscopically derived abundances and velocities. Our clusters span a wide range of ages and provide good areal coverage of the galaxy.
292. CaII transmission spectrum of WASP-33b and KELT-9b
ID:
ivo://CDS.VizieR/J/A+A/632/A69
Title:
CaII transmission spectrum of WASP-33b and KELT-9b
Short Name:
J/A+A/632/A69
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ultra-hot Jupiters are emerging as a new class of exoplanets. Studying their chemical compositions and temperature structures will improve the understanding of their mass loss rate as well as their formation and evolution. We present the detection of ionized calcium in the two hottest giant exoplanets - KELT-9b and WASP-33b. By utilizing transit datasets from CARMENES and HARPS-N observations, we achieved high confidence level detections of CaII using the cross-correlation method. We further obtain the transmission spectra around the individual lines of the CaII H&K doublet and the near-infrared triplet, and measure their line profiles. The CaII H&K lines have an average line depth of 2.02+/-0.17% (effective radius of 1.56Rp) for WASP-33b and an average line depth of 0.78+/-0.04% (effective radius of 1.47Rp) for KELT-9b, which indicates that the absorptions are from very high upper atmosphere layers close to the planetary Roche lobes. The observed CaII lines are significantly deeper than the predicted values from the hydrostatic models. Such a discrepancy is probably a result of hydrodynamic outflow that transports a significant amount of CaII into the upper atmosphere. The prominent CaII detection with the lack of significant CaI detection implies that calcium is mostly ionized in the upper atmospheres of the two planets.
293. Ca II triplet lines in cool stars
ID:
ivo://CDS.VizieR/J/A+AS/124/359
Title:
Ca II triplet lines in cool stars
Short Name:
J/A+AS/124/359
Date:
21 Oct 2021
Publisher:
CDS
Description:
CCD spectra of the infrared triplet lines of ionized calcium at {lambda}{lambda}8498, 8542, 8662 have been obtained at a spectral resolution of 0.4{AA} in 146 stars brighter than V=+7.0 spanning a range in spectral types from F7 to M4 of all luminosity classes and a range in metallicity [Fe/H] from -3.0 to +1.1. These have been analysed to investigate the dependence of the Ca II triplet strengths on stellar parameters like luminosity, temperature and metallicity. A detailed study reveals a strong dependence on luminosity, much stronger for metal rich stars than for the metal poor ones and a milder dependence on metallicity, although much more conspicuous in supergiants than in dwarfs. All these correlations are found to be non-linear over the parameter space covered. The present study also shows chromospheric activity to be an important phenomenon affecting the strength and the shape of the line profiles. Stars of similar luminosity and metallicity have varying Ca II line depths owing to varying chromospheric emission filling in their Ca II absorption. The Ca II triplet strength is thus observed to be a triparametric discriminant in cool stars.
294. CaII triplet of RGB from VLT/FLAMES obs.
ID:
ivo://CDS.VizieR/J/MNRAS/383/183
Title:
CaII triplet of RGB from VLT/FLAMES obs.
Short Name:
J/MNRAS/383/183
Date:
21 Oct 2021
Publisher:
CDS
Description:
We demonstrate that low-resolution CaII triplet (CaT) spectroscopic estimates of the overall metallicity ([Fe/H]) of individual red giant branch (RGB) stars in two nearby dwarf spheroidal galaxies (dSphs) agree to +/-0.1-0.2dex with detailed high-resolution spectroscopic determinations for the same stars over the range -2.5<[Fe/H]<-0.5. For this study, we used a sample of 129 stars observed in low- and high-resolution modes with VLT/FLAMES in the Sculptor and Fornax dSphs. We also present the data-reduction steps we used in our low-resolution analysis and show that the typical accuracy of our velocity and CaT [Fe/H] measurement is ~2km/s and 0.1dex, respectively. We conclude that CaT[Fe/H] relations calibrated on globular clusters can be applied with confidence to RGB stars in composite stellar populations over the range -2.5<[Fe/H]<-0.5.
295. Ca4227 indices in early-type galaxies
ID:
ivo://CDS.VizieR/J/AJ/130/2666
Title:
Ca4227 indices in early-type galaxies
Short Name:
J/AJ/130/2666
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have investigated the abundance of calcium in early-type galaxies by measuring the strength of the CaI {lambda}4227 absorption line in their integrated spectra. The database used is the large sample of early-type galaxy integrated spectra in Caldwell and coworkers (2003AJ....125.2891C). We have measured Ca abundances from the CaI {lambda}4227 feature both by using the Lick Ca4227 index and by defining a new index, Ca4227_r_, that avoids the CN4216 molecular band in the continuum on the blueward side of the line.
296. Calcium triplet index in LMC stars
ID:
ivo://CDS.VizieR/J/AJ/135/836
Title:
Calcium triplet index in LMC stars
Short Name:
J/AJ/135/836
Date:
21 Oct 2021
Publisher:
CDS
Description:
Infrared CaII triplet (CaT) spectroscopy has been used to derive stellar metallicities for individual stars in four Large Magellanic Cloud fields situated at galactocentric distances of 3{deg}, 5{deg}, 6{deg}, and 8{deg} to the north of the bar. The combination of spectroscopy with deep CCD photometry has allowed us to break the RGB age-metallicity degeneracy and compute the ages for the objects observed spectroscopically. The obtained age-metallicity relationships (AMRs) for our four fields are statistically indistinguishable. We conclude that the lower mean metallicity in the outermost field is a consequence of it having a lower fraction of intermediate-age stars, which are more metal-rich than the older stars. The disk AMR is similar to that for clusters. However, the lack of objects with ages between 3 and 10Gyr is not observed in the field population. Finally, we used data from the literature to derive consistently the AMR of the bar. Simple chemical evolution models have been used to reproduce the observed AMRs with the purpose of investigating which mechanism has participated in the evolution of the disk and bar.
297. CALIFA DR3
ID:
ivo://org.gavo.dc/califa/q3/s
Title:
CALIFA DR3
Short Name:
califa ssa
Date:
27 Dec 2024 08:31:03
Publisher:
The GAVO DC team
Description:
Split spectra from the CALIFA DR3 cubes. This service serves one spectrum each per pixel in each cube where there is at least one valid spaxel. Where both V500 and COMB data is available, COMB spectra are served. WARNING: The individual spectra are not independent. Also, error estimates over wide spectral ranges based on the error estimates served here are unreliable.
298. CALIFA DR3 tables
ID:
ivo://org.gavo.dc/califa/q3/tables
Title:
CALIFA DR3 tables
Date:
14 Aug 2024 00:01:52
Publisher:
The GAVO DC team
Description:
The Calar Alto Legacy Integral Field Area (CALIFA) survey provides spatially resolved spectroscopic information for 667 galaxies, mainly within the local universe (0.005 < z < 0.03). CALIFA data was obtained using the PPAK integral field unit (IFU), with a hexagonal field-of-view of 1.3 square arcmin, with a 100% covering factor by adopting a three-pointing dithering scheme. has been taken in two setups: V500 (6 Å bin size, 646 galaxies) and V1200 (2.3 Å bin size, 484 galaxies). A final product ("COMBO") combining both data sets, covering 3700-7500 Å at 6 Å bin size, is made availble for 484 galaxies. CALIFA is a legacy survey, intended for the community. This is the (final) Data Release 3. This is the VO/TAP publication with a simple web interface on top. See http://califa.caha.es/ for the upstream site.
299. CALIFA galaxies observational hints
ID:
ivo://CDS.VizieR/J/A+A/604/A4
Title:
CALIFA galaxies observational hints
Short Name:
J/A+A/604/A4
Date:
21 Oct 2021
Publisher:
CDS
Description:
According to numerical simulations, stars are not always kept at their birth galactocentric distances but migrate. The importance of this radial migration in shaping galactic light distributions is still unclear. However, if it is indeed important, galaxies with different surface brightness (SB) profiles must display differences in their stellar population properties. We investigate the role of radial migration on the light distribution and the radial stellar content by comparing the inner colour, age and metallicity gradients for galaxies with different SB profiles. We define these inner parts avoiding the bulge and bar regions and up to around three disc scale lengths (type I, pure exponential) or the break radius (type II, downbending; type III, upbending). We analyse 214 spiral galaxies from the CALIFA survey covering different SB profiles. We make use of GASP2D and SDSS data to characterise their light distribution and obtain colour profiles. The stellar age and metallicity profiles are computed using a methodology based on full-spectrum fitting techniques (pPXF, GANDALF, and STECKMAP) to the IFS CALIFA data. The distributions of the colour, stellar age and stellar metallicity gradients in the inner parts for galaxies displaying different SB profiles are unalike as suggested by Kolmogorov-Smirnov and Anderson-Darling tests. We find a trend in which type II galaxies show the steepest profiles of all and type III the shallowest, with type I galaxies displaying an intermediate behaviour. These results are consistent with a scenario in which radial migration is more efficient for type III galaxies than for type I systems with type II galaxies presenting the lowest radial migration efficiency. In such scenario, radial migration mixes the stellar content flattening the radial stellar properties and shaping different SB profiles. However, in sight of these results we cannot further quantify its importance in shaping spiral galaxies, and other processes such as recent star formation or satellite accretion might play a role.
300. CALIFA SFRs. II. Bulges, bars & disks
ID:
ivo://CDS.VizieR/J/ApJ/848/87
Title:
CALIFA SFRs. II. Bulges, bars & disks
Short Name:
J/ApJ/848/87
Date:
21 Oct 2021
Publisher:
CDS
Description:
We estimate the current extinction-corrected H{alpha} star formation rate (SFR) of the different morphological components that shape galaxies (bulges, bars, and disks). We use a multicomponent photometric decomposition based on Sloan Digital Sky Survey imaging to Calar Alto Legacy Integral Field Area Integral Field Spectroscopy (IFS) datacubes for a sample of 219 galaxies. This analysis reveals an enhancement of the central SFR and specific SFR (sSFR = SFR/M*) in barred galaxies. Along the main sequence, we find that more massive galaxies in total have undergone efficient suppression (quenching) of their star formation, in agreement with many studies. We discover that more massive disks have had their star formation quenched as well. We evaluate which mechanisms might be responsible for this quenching process. The presence of type 2 AGNs plays a role at damping the sSFR in bulges and less efficiently in disks. Also, the decrease in the sSFR of the disk component becomes more noticeable for stellar masses around 10^10.5^M_{sun}_; for bulges, it is already present at ~10^9.5^M_{sun}_. The analysis of the line- of-sight stellar velocity dispersions ({sigma}) for the bulge component and of the corresponding Faber-Jackson relation shows that AGNs tend to have slightly higher {sigma} values than star-forming galaxies for the same mass. Finally, the impact of environment is evaluated by means of the projected galaxy density, {Sigma}5. We find that the SFR of both bulges and disks decreases in intermediate- to high-density environments. This work reflects the potential of combining IFS data with 2D multicomponent decompositions to shed light on the processes that regulate the SFR.

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