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5001. Photometry and lines of (z~0.2-1.0) galaxies
ID:
ivo://CDS.VizieR/J/A+A/448/893
Title:
Photometry and lines of (z~0.2-1.0) galaxies
Short Name:
J/A+A/448/893
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the spectrophotometric properties of a sample of 141 emission-line galaxies at redshifts in the range 0.2<z<1.0 with a peak around 0.2<=z<=0.4. The analysis is based on medium resolution (Rs=500-600), optical spectra obtained at VLT and Keck. The targets are mostly "Canada-France Redshift Survey" (<VII/225>) emission-line galaxies, with the addition of field galaxies randomly selected behind lensing clusters. We complement this sample with galaxy spectra from the "Gemini Deep Deep Survey" (<J/AJ/127/2455>) public data release. We have computed absolute magnitudes of the galaxies and measured the line fluxes and equivalent widths of the main emission/absorption lines. The last two have been measured after careful subtraction of the fitted stellar continuum using the platefit software originally developed for the SDSS and adapted to our data. We present a careful comparison of this software with the results of manual measurements.
5002. Photometry and Metallicity in ABCG 209 galaxies
ID:
ivo://CDS.VizieR/J/A+A/424/79
Title:
Photometry and Metallicity in ABCG 209 galaxies
Short Name:
J/A+A/424/79
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse the properties of galaxy populations in the rich Abell cluster ABCG 209 at redshift z~0.21, on the basis of spectral classification of 102 member galaxies. We take advantage of available structural parameters to study separately the properties of bulge-dominated and disk-dominated galaxies. The star formation histories of the cluster galaxy populations are investigated by using line strengths and the 4000{AA} break, through a comparison to stellar population synthesis models. The dynamical properties of different spectral classes are examined in order to infer the past merging history of ABCG 209. The cluster is characterized by the presence of two components: an old galaxy population, formed very early (z_f>~3.5), and a younger (z_f>~1.2) population of infalling galaxies. We find evidence of a merger with an infalling group of galaxies occurred 3.5-4.5Gyr ago. The correlation between the position of the young H_delta-strong galaxies and the X-ray flux shows that the hot intracluster medium triggered a starburst in this galaxy population ~3Gyr ago.
5003. Photometry and models of long-period asteroids
ID:
ivo://CDS.VizieR/J/A+A/610/A7
Title:
Photometry and models of long-period asteroids
Short Name:
J/A+A/610/A7
Date:
21 Oct 2021
Publisher:
CDS
Description:
The available set of spin and shape modelled asteroids is strongly biased against slowly rotating targets and those with low lightcurve amplitudes. This is due to the observing selection effects. As a consequence, the current picture of asteroid spin axis distribution, rotation rates, radiometric properties, or aspects related to the object's internal structure might be affected too. To counteract these selection effects, we are running a photometric campaign of a large sample of main belt asteroids omitted in most previous studies. Using least chi-squared fitting we determined synodic rotation periods and verified previous determinations. When a dataset for a given target was sufficiently large and varied, we performed spin and shape modelling with two different methods to compare their performance. We used the convex inversion method and the non-convex SAGE algorithm, applied on the same datasets of dense lightcurves. Both methods search for the lowest deviations between observed and modelled lightcurves, though using different approaches. Unlike convex inversion, the SAGE method allows for the existence of valleys and indentations on the shapes based only on lightcurves. We obtain detailed spin and shape models for the first five targets of our sample: (159) Aemilia, (227) Philosophia, (329) Svea, (478) Tergeste, and (487) Venetia. When compared to stellar occultation chords, our models obtained an absolute size scale and major topographic features of the shape models were also confirmed. When applied to thermophysical modelling (TPM), they provided a very good fit to the infrared data and allowed their size, albedo, and thermal inertia to be determined. Convex and non-convex shape models provide comparable fits to lightcurves. However, some non-convex models fit notably better to stellar occultation chords and to infrared data in sophisticated thermophysical modelling (TPM). In some cases TPM showed strong preference for one of the spin and shape solutions. Also, we confirmed that slowly rotating asteroids tend to have higher-than-average values of thermal inertia, which might be caused by properties of the surface layers underlying the skin depth.
5004. Photometry and motions in Arches and Quintuplet
ID:
ivo://CDS.VizieR/J/A+A/578/A4
Title:
Photometry and motions in Arches and Quintuplet
Short Name:
J/A+A/578/A4
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the circumstellar disc fraction as determined from L-band excess observations of the young, massive Arches and Quintuplet clusters residing in the central molecular zone of the Milky Way. The Quintuplet cluster was searched for L-band excess sources for the first time. We find a total of 26 excess sources in the Quintuplet cluster, and 21 sources with L-band excesses in the Arches cluster, of which 13 are new detections. With the aid of proper motion membership samples, the disc fraction of the Quintuplet cluster could be derived for the first time to be 4.0+/-0.7. There is no evidence for a radially varying disc fraction in this cluster. In the case of the Arches cluster, a disc fraction of 9.2+/-1.2 approximately out to the cluster's predicted tidal radius, r<1.5pc (Habibi et al., 2013A&A...556A..26H, Cat. J/A+A/556/A26), is found. This excess fraction is consistent with our previously found disc fraction in the cluster in the radial range 0.3<r<0.8pc. In both clusters, the host star mass range covers late A to early B-type stars, 2<M<15M_{sun}, as derived from J-band photospheric magnitudes. We discuss the unexpected finding of dusty circumstellar discs in these UV intense environments in the context of primordial disc survival and formation scenarios of secondary discs. We consider the possibility that the L-band excess sources in the Arches and Quintuplet clusters could be the high-mass counterparts to T Tauri pre-transitional discs. As such a scenario requires a long pre-transitional disc lifetime in a UV intense environment, we suggest that mass transfer discs in binary systems are a likely formation mechanism for the B-star discs observed in these starburst clusters.
5005. Photometry and polarimetry of Ae star VV Ser
ID:
ivo://CDS.VizieR/J/AZh/78/60
Title:
Photometry and polarimetry of Ae star VV Ser
Short Name:
J/AZh/78/60
Date:
21 Oct 2021
Publisher:
CDS
Description:
Results of long-term photometric and polarimetric observations of the classical Herbig Ae star VV Ser, performed at the Crimean Astrophysical Observatory as part of a program of photometric and polarimetric monitoring of UX Ori stars are presented.
5006. Photometry and proper motions in IC4665
ID:
ivo://CDS.VizieR/J/A+A/532/A103
Title:
Photometry and proper motions in IC4665
Short Name:
J/A+A/532/A103
Date:
21 Oct 2021
Publisher:
CDS
Description:
Knowledge of the mass function in open clusters constitutes one way to constrain the formation of low-mass stars and brown dwarfs along with the knowledge of the frequency of multiple systems and the properties of disks. The aim of the project is to determine the shape of the mass function in the low-mass and substellar regimes in the pre-main sequence (27Myr) cluster IC4665 located at 350pc from the Sun. We have cross-matched the near-infrared photometric data from the Eighth Data Release (DR8) of the UKIRT Infrared Deep Sky Survey (UKIDSS) Galactic Clusters Survey (GCS) with previous optical data obtained with the Canada-France-Hawaii (CFH) wide-field camera to improve the determination of the luminosity and mass functions in the low-mass and substellar regimes. The availability of i and z photometry taken with the CFH12K camera on the Canada France Hawaii Telescope added strong constraints to the UKIDSS photometric selection in this cluster located in a dense region of our Galaxy. We have derived the luminosity and mass functions of the cluster down to J=18.5mag, corresponding to masses of ~0.025M_{sun}_ at the distance and age of IC4665 according to theoretical models. In addition, we have extracted new candidate members down to ~20 Jupiter masses in a previously unstudied region of the cluster. We have derived the mass function over the 0.6-0.04M_{sun}_ mass range and found that it is best represented by a log-normal function with a peak at 0.25-0.16M_{sun}_, consistent with the determination in the Pleiades.
5007. Photometry and Proper Motions in M67
ID:
ivo://CDS.VizieR/V/52
Title:
Photometry and Proper Motions in M67
Short Name:
V/52
Date:
21 Oct 2021
Publisher:
CDS
Description:
Relative proper motions were determined for 1068 stars with limiting magnitude b=16.5 and located within an area 130'*130' centered at alpha=8h 47.7m,delta=+12 deg.00' and l=215.6deg.,b=+31.2deg.(1950.0). Five plate pairs taken with the Pulkovo normal astrograph with mean epoch difference of 62 years were used. The proper motions have a mean error of 0''.0020 per year and were measured relative to reference stars with 13.5<b<14.5. Photographic UBV magnitudes were determined using the photoelectric standards of Johnson, Sandage (1955ApJ...121..616J) and Eggen, Sandage (1964ApJ...140..130E). Three plates in each colour taken with the Schmidt telescope of the Radioastrophysical Observatory of the Latvian SSR were measured. In addition a plate taken with the Pulkovo 26inch telescope was used to determine v-magnitudes. The cluster members were selected on the basis of proper motion (vector point diagram) and photometric (V/B-V and U-B/B-V) criteria.
5008. Photometry and proper motions in Praesepe
ID:
ivo://CDS.VizieR/J/ApJ/784/57
Title:
Photometry and proper motions in Praesepe
Short Name:
J/ApJ/784/57
Date:
21 Oct 2021
Publisher:
CDS
Description:
Membership identification is the first step in determining the properties of a star cluster. Low-mass members in particular could be used to trace the dynamical history, such as mass segregation, stellar evaporation, or tidal stripping, of a star cluster in its Galactic environment. We identified member candidates of the intermediate-age Praesepe cluster (M44) with stellar masses ~0.11-2.4M_{sun}_, using Panoramic Survey Telescope And Rapid Response System and Two Micron All Sky Survey photometry, and PPMXL proper motions. Within a sky area of 3{deg} radius, 1040 candidates are identified, of which 96 are new inclusions. Using the same set of selection criteria on field stars, an estimated false positive rate of 16% was determined, suggesting that 872 of the candidates are true members. This most complete and reliable membership list allows us to favor the BT-Settl model over other stellar models. The cluster shows a distinct binary track above the main sequence, with a binary frequency of 20%-40%, and a high occurrence rate of similar mass pairs. The mass function is consistent with that of the disk population but shows a deficit of members below 0.3 solar masses. A clear mass segregation is evidenced, with the lowest-mass members in our sample being evaporated from this disintegrating cluster.
5009. Photometry and radial velocities in NGC752
ID:
ivo://CDS.VizieR/J/PASP/106/281
Title:
Photometry and radial velocities in NGC752
Short Name:
J/PASP/106/281
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using all available proper-motion and radial-velocity data, including new radial-velocity observations obtained for this investigation, probable members of the open cluster NGC 752 have been identified. Photoelectric data on six systems have been transformed and collated to form an internally consistent sample on the BV system. Binaries have been identified using photometric and radial-velocity data, including a photographic survey for variability and the radial-velocity observations of this study. Analysis of the data leads to the following cluster parameters and their probable errors: E(B-V) = 0.035+/-0.005mag, Fe/H = -0.15+/-0.05dex, and (m-M) = 8.25+/-0.10mag. The spread in color among stars in the color-magnitude diagram (CMD) along the main sequence from the turnoff to the unevolved main sequence is the consequence of a rich population of binaries. Due to its age and the comprehensive data available for the cluster, NGC 752 provides an ideal test of a variety of evolutionary phenomena. Comparison with theoretical isochrones normalized in an internally consistent manner leads to the conclusion that the morphology and distribution of stars in the CMD can best be matched using models that include convective overshoot, particularly those of Schaller et al. (1992A&AS...96..269S). Despite their differences, the traditional and the overshoot isochrones both imply very similar ages, 1.9+/-0.2Gyr and 1.7+/-0.1Gyr, respectively, for the cluster.
5010. Photometry and radial velocities of K2-131
ID:
ivo://CDS.VizieR/J/AJ/154/226
Title:
Photometry and radial velocities of K2-131
Short Name:
J/AJ/154/226
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of a new ultra-short-period planet and summarize the properties of all such planets for which the mass and radius have been measured. The new planet, K2-131b, was discovered in K2 Campaign 10. It has a radius of 1.81_-0.12_^+0.16^ R_{Earth}_ and orbits a G dwarf with a period of 8.9 hr. Radial velocities obtained with Magellan/PFS and TNG/HARPS-N show evidence for stellar activity along with orbital motion. We determined the planetary mass using two different methods: (1) the "floating chunk offset" method, based only on changes in velocity observed on the same night; and (2) a Gaussian process regression based on both the radial velocity and photometric time series. The results are consistent and lead to a mass measurement of 6.5+/-1.6 M_{Earth}_ and a mean density of 6.0_-2.7_^+3.0^ g/cm^3^.