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3521. (S+S) binary galaxies BVRI photometry
ID:
ivo://CDS.VizieR/J/A+A/379/54
Title:
(S+S) binary galaxies BVRI photometry
Short Name:
J/A+A/379/54
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present multicolour broad band (BVRI) photometry for a sample of 33 spiral-spiral (S+S) binary galaxies drawn from the Karachentsev Catalogue of Isolated Pairs of Galaxies (KPG, Cat. <VII/77>). The data is part of a joint observational programme devoted to systematic photometric study of one of the most complete and homogeneous pair samples available in the literature. We present azimuthally averaged colour and surface brightness profiles, colour index (B-I) maps, B band and sharp/filtered B band images as well as integrated magnitudes, magnitudes at different circular apertures and integrated colours for each pair. Internal and external data comparisons show consistency within the estimated errors. Two thirds of the sample have total aperture parameters homogeneously derived for the first time. After reevaluating morphology for all the pairs, we find a change in Hubble type for 24 galaxies compared to the original POSS classifications. More than half of our pairs show morphological concordance which could explain, in part, the strong correlation in the (B-V) colour indices (Holmberg Effect) between pair components. We find a tendency for barred galaxies to show grand design morphologies and flat colour profiles. The measurements will be used in a series of forthcoming papers where we try to identify and isolate the main structural and photometric properties of disk galaxies at different stages of interaction.
3522. SS 433 UBVRI light curves
ID:
ivo://CDS.VizieR/J/other/PZ/31.5
Title:
SS 433 UBVRI light curves
Short Name:
J/other/PZ/31.5
Date:
21 Oct 2021
Publisher:
CDS
Description:
After 33 years of extensive studies of SS 433, we have learnt much about this unique system with moving emission lines in the spectrum. The orbital inclination is known from spectroscopic observations of moving lines; the distance is derived from radio interferometry of relativistic jets; the mass ratio of its components is determined from X-ray observations of jets' eclipses. In 2005, the accretion donor was detected as an A4-A8 giant, and its contribution to eclipse light was measured spectroscopically. In the present paper, the A-type star was detected via multicolor photometry on the basis of its Balmer jump. A method is proposed to estimate the interstellar reddening, able to measure the individual law of interstellar absorption for SS 433 from spectrophotometry.
3523. Standard Galactic field RR Lyrae. I. Photometry
ID:
ivo://CDS.VizieR/J/AJ/153/96
Title:
Standard Galactic field RR Lyrae. I. Photometry
Short Name:
J/AJ/153/96
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a multi-wavelength compilation of new and previously published photometry for 55 Galactic field RR Lyrae variables. Individual studies, spanning a time baseline of up to 30 years, are self-consistently phased to produce light curves in 10 photometric bands covering the wavelength range from 0.4 to 4.5 microns. Data smoothing via the GLOESS technique is described and applied to generate high-fidelity light curves, from which mean magnitudes, amplitudes, rise times, and times of minimum and maximum light are derived. 60000 observations were acquired using the new robotic Three-hundred MilliMeter Telescope (TMMT), which was first deployed at the Carnegie Observatories in Pasadena, CA, and is now permanently installed and operating at Las Campanas Observatory in Chile. We provide a full description of the TMMT hardware, software, and data reduction pipeline. Archival photometry contributed approximately 31000 observations. Photometric data are given in the standard Johnson UBV, Kron-Cousins R_C_I_C_, 2MASS JHK, and Spitzer [3.6] and [4.5] bandpasses.
3524. Standard magnitudes in the E regions
ID:
ivo://CDS.VizieR/II/222
Title:
Standard magnitudes in the E regions
Short Name:
II/222
Date:
21 Oct 2021
Publisher:
CDS
Description:
A single table combines the revised and extended results of 24 series of photometric observations made in South Africa between 1947 and 1960 on the nine Harvard E regions at declination -45{deg}. For each of about 90 stars in each region are tabulated V and B-V on the standard U,B,V system, an ultraviolet-free blue magnitude S'Pg, a photovisual magnitude SPv and, in most cases, an ultraviolet minus blue colour (U-B)_C_. The internal standard error of an entry is +/-0.01mag or less.
3525. StarCAT: STIS UV echelle spectra of stars
ID:
ivo://CDS.VizieR/J/ApJS/187/149
Title:
StarCAT: STIS UV echelle spectra of stars
Short Name:
J/ApJS/187/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
StarCAT is a catalog of high resolution ultraviolet spectra of objects classified as "stars," recorded by Space Telescope Imaging Spectrograph (STIS) during its initial seven years of operations (1997-2004). StarCAT is based on 3184 echelle observations of 545 distinct targets, with a total exposure duration of 5.2Ms. For many of the objects, broad ultraviolet coverage has been achieved by splicing echellegrams taken in two or more FUV (1150-1700{AA}) and/or NUV (1600-3100{AA}) settings. In cases of multiple pointings on conspicuously variable sources, spectra were separated into independent epochs. Otherwise, different epochs were combined to enhance the signal-to-noise ratio (S/N). A post-facto correction to the "calstis" pipeline data sets compensated for subtle wavelength distortions identified in a previous study of the STIS calibration lamps. An internal "fluxing" procedure yielded coherent spectral energy distributions (SEDs) for objects with broadly overlapping wavelength coverage. The best StarCAT material achieves 300m/s internal velocity precision; absolute accuracy at the 1km/s level; photometric accuracy of order 4%; and relative flux precision several times better (limited mainly by knowledge of SEDs of UV standard stars). While StarCAT represents a milestone in the large-scale post-processing of STIS echellegrams, a number of potential improvements in the underlying "final" pipeline are identified.
3526. 35 star clusters and fields in the SMC
ID:
ivo://CDS.VizieR/J/A+A/647/A135
Title:
35 star clusters and fields in the SMC
Short Name:
J/A+A/647/A135
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this work we study 35 stellar clusters in the Small Magellanic Cloud (SMC) in order to provide their mean metallicities and ages. We also provide mean metallicities of the fields surrounding the clusters. We used Stroemgren photometry obtained with the 4.1 m SOAR telescope and take advantage of (b-y) and m1 colors for which there is a metallicity calibration presented in the literature. The spatial metallicity and age distributions of clusters across the SMC are investigated using the results obtained by Stroemgren photometry. We confirm earlier observations that younger, more metal-rich star clusters are concentrated in the central regions of the galaxy, while older, more metal-poor clusters are located farther from the SMC center. We construct the age-metallicity relation for the studied clusters and find good agreement with theoretical models of chemical enrichment, and with other literature age and metallicity values for those clusters. We also provide the mean metallicities for old and young populations of the field stars surrounding the clusters, and find the latter to be in good agreement with recent studies of the SMC Cepheid population. Finally, the Stroemgren photometry obtained for this study is made publicly available.
3527. Star clusters in IC 10
ID:
ivo://CDS.VizieR/J/ApJ/804/123
Title:
Star clusters in IC 10
Short Name:
J/ApJ/804/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a survey of star clusters in the halo of IC 10, a starburst galaxy in the Local Group, based on Subaru R-band images and NOAO Local Group Survey UBVRI images. We find five new star clusters. All of these star clusters are located far from the center of IC 10, while previously known star clusters are mostly located in the main body. Interestingly, the distribution of these star clusters shows an asymmetrical structure elongated along the east and southwest directions. We derive UBVRI photometry of 66 star clusters, including these new star clusters, as well as previously known star clusters. Ages of the star clusters are estimated from a comparison of their UBVRI spectral energy distribution with the simple stellar population models. We find that the star clusters in the halo are all older than 1Gyr, while those in the main body have various ages, from very young (several Myr) to old (>1Gyr). The young clusters (<10Myr) are mostly located in the H{alpha} emission regions and are concentrated on a small region at 2" in the southeast direction from the galaxy center, while the old clusters are distributed in a wider area than the disk. Intermediate-age clusters (~100 Myr) are found in two groups. One is close to the location of the young clusters and the other is at ~ 4" from the location of the young clusters. The latter may be related to past mergers or tidal interaction.
3528. Star Clusters in M33
ID:
ivo://CDS.VizieR/J/ApJS/122/431
Title:
Star Clusters in M33
Short Name:
J/ApJS/122/431
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we present the discovery of 60 star clusters in 20 multiband Hubble Space Telescope (HST) WFPC2 fields in M33. The fields sample a variety of environments, from outer regions to spiral arms and central regions, as well as a range of galactocentric distances. The HST spatial resolution allowed us to penetrate the crowded, spiral arm regions of M33 yielding the first unbiased, representative sample of star clusters for this galaxy. We discuss the separation of clusters from stellar sources, and from other extended sources such as star-forming regions, H II regions, and supernova remnants. For the clusters we present multiband images and discuss morphology, location, and integrated photometry. Measured cluster colors and magnitudes are presented. The cluster density in our sample as a function of galactocentric distance yields an estimate of 690 total clusters in M33.
3529. Star clusters in M31
ID:
ivo://CDS.VizieR/J/ApJS/177/174
Title:
Star clusters in M31
Short Name:
J/ApJS/177/174
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new survey of star clusters in the southwest field of the M31 disk based on the high-resolution Subaru Suprime-Cam observations is presented. The UBVRI aperture CCD photometry catalog of 285 objects (V<~20.5mag; 169 of them identified for the first time) is provided. Each object is supplemented with multiband color maps presented in the electronic edition of the Astrophysical Journal Supplement. Seventy-seven star cluster candidates from the catalog are located in the Hubble Space Telescope archive frames.
3530. Star formation in Centaurus A Group dwarfs
ID:
ivo://CDS.VizieR/J/AJ/138/1037
Title:
Star formation in Centaurus A Group dwarfs
Short Name:
J/AJ/138/1037
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present H{alpha} narrow-band imaging of 17 dwarf irregular (dI) galaxies in the nearby Centaurus A Group. Although all large galaxies of the group are or recently have been through a period of enhanced star formation, the dIs have normal star formation rates (SFRs) and do not contain a larger fraction of dwarf starbursts than other nearby groups such as the Sculptor Group or the Local Group. Most of the galaxies in the group now have fairly accurately known distances, which enables us to obtain relative distances between dIs and larger galaxies of the group. We find four transition dwarfs in the Group, dwarfs that show characteristics of both dE/dSphs and dIs, and which contain cold gas but no current star formation.