- ID:
- ivo://CDS.VizieR/J/ApJ/716/942
- Title:
- Bulges of nearby galaxies with Spitzer
- Short Name:
- J/ApJ/716/942
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate scaling relations of bulges using bulge-disk decompositions at 3.6um and present bulge classifications for 173 E-Sd galaxies within 20Mpc. Pseudobulges and classical bulges are identified using Sersic index, Hubble Space Telescope morphology, and star formation activity (traced by 8um emission). In the near-IR pseudobulges have n_b_<2 and classical bulges have n_b_>2, as found in the optical. Sersic index and morphology are essentially equivalent properties for bulge classification purposes. We confirm, using a much more robust sample, that the Sersic index of pseudobulges is uncorrelated with other bulge structural properties, unlike for classical bulges and elliptical galaxies. Also, the half-light radius of pseudobulges is not correlated with any other bulge property. We also find a new correlation between surface brightness and pseudobulge luminosity; pseudobulges become more luminous as they become more dense.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/465/943
- Title:
- BVI and RV curves of 5 eclipsing binaries
- Short Name:
- J/A+A/465/943
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We detected tertiary components of close binaries from spectroscopy and light curve modelling, investigated the light-travel time effect and the possibility of magnetic activity cycles, measured mass ratios for unstudied systems, and derived absolute parameters. We carried out new photometric and spectroscopic observations of five bright close eclipsing binaries, predominantly in the southern skies. We obtained full Johnson BV light curves, which were modelled with the Wilson-Devinney code. Radial velocities were measured with the cross-correlation method using IAU radial velocity standards as spectral templates. Period changes were studied with the O-C method, utilising published epochs of minimum light (XY Leo) and ASAS photometry (VZ Lib). For three objects (DX Tuc, QY Hya, V870 Ara), absolute parameters have been determined for the first time. We spectroscopically detected the tertiary components in XY Leo and VZ Lib and discovered one in QY Hya. For XY Leo we updated the light-time effect parameters and detected a secondary periodicity of about 5100d in the O-C diagram that may hint at the existence of short-period magnetic cycles. A combination of recent photometric data shows that the orbital period of the tertiary star in VZ Lib is likely to be over 1500d. QY Hya is a semi-detached X-ray active binary in a triple system with K and M-type components, while V870 Ara is a contact binary with the third smallest spectroscopic mass ratio for a W UMa star to date. Being close to the theoretical minimum for contact binaries, this small mass ratio suggests that V870 Ara has the potential of constraining evolutionary scenarios of binary mergers. The inferred distances to these systems are compatible with the Hipparcos parallaxes.
- ID:
- ivo://CDS.VizieR/J/other/Obs/131.386
- Title:
- BVIc light curves of 8 RR Lyr-type stars
- Short Name:
- J/other/Obs/131.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We took a total of 1175 B, V, and Ic-band CCD frames for 11 GCVS RR Lyr-type variables, for which only the coordinates were known. Observations were made with the 76-crn telescope of the South African Astronomical Observatory. We confirm the variability types, determine the periods, and build the light curves for five objects: BL Aps (P=0.598d), GR Pav (P=0.583d), HI Pav (P=0.643d), HZ Pav (P=0.803d), and IR Pav (P=0.561d). The objects SY Aps (P=0.279d) and IV Pav (P=0.408d) proved to be W UMa-type eclipsing variables; TW Aps (P=0.149d), an SX Phe-type variable; TT Aps (P=482d), an SRD-type semiregular variable, and SW Aps and GI Pav, constant stars.
- ID:
- ivo://CDS.VizieR/J/ApJS/137/209
- Title:
- BVIc photoelectric obs. of southern Cepheids
- Short Name:
- J/ApJS/137/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A total of 2097 photometric observations in the BVI_C_ system are presented for 117 Cepheids located in the southern hemisphere. The main purpose of the photometry is to provide new epochs of maximum brightness for studying Cepheid period changes, as well as to establish current light elements for the Cepheids.
- ID:
- ivo://CDS.VizieR/J/other/NewA/11.262
- Title:
- BVIc photometry in Lynga 11
- Short Name:
- J/other/NewA/11.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained CCD BVI_KC_ photometry down to V~21.5 for the open cluster Lynga 11 and its surrounding field. This previously unstudied object appears to be rich and highly absorbed. A cluster angular radius of 4.5+/-0.5, equivalent to (3.0+/-0.3)pc, is estimated from star counts in 100-pixel a side boxes distributed throughout the whole observed field. Our analysis suggests that Lynga 11 is moderately young and probably of solar metallicity.
- ID:
- ivo://CDS.VizieR/J/AZh/88/886
- Title:
- BVIc photometry of Cepheids from ASAS-3 catalog
- Short Name:
- J/AZh/88/886
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In 2008-2010, we obtained 6095 CCD frames in the BVIc photometric system for 49 classical Cepheids discovered in the ASAS-3 project. The observations were obtained on the 76-cm telescope of the South African Astronomical Observatory (SAAO, RSA) and the 40-cm telescope of the Cerro Armazones Observatory of the Catholic University of the North (OCA, Chile), with a SBIGCCD ST-10XME camera. We present tabulated observations, light curves, and revised elements for the brightness variations.
- ID:
- ivo://CDS.VizieR/J/AJ/140/677
- Title:
- BVIc photometry of IC 4665
- Short Name:
- J/AJ/140/677
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new, BVIc photometric survey of the young open cluster IC 4665, which improves on previous studies of this young cluster by incorporating a rigorous standardization procedure, thus providing high-fidelity colors and magnitudes for cluster members. We use this new photometric dataset to reevaluate the properties (age and distance) of IC 4665.
- ID:
- ivo://CDS.VizieR/J/PASJ/56/295
- Title:
- BVIc photometry of old open clusters
- Short Name:
- J/PASJ/56/295
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new photometric data for 14 galactic open clusters taken by the 65cm telescope at Gunma Astronomical Observatory. They were in the anti-galactic center region selected from the Catalog of Open Cluster Data (Lynga, 1987, See Cat. <J/A+A/438/1163>). We estimated the parameters of the clusters, i.e., age, metallicity, distance, and reddening, by fitting Padova isochrones to the color-magnitude diagram.
- ID:
- ivo://CDS.VizieR/J/MNRAS/391/1482
- Title:
- BVIc photometry of Trumpler 20
- Short Name:
- J/MNRAS/391/1482
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We show that the open cluster Trumpler 20, contrary to the earlier findings, is actually an old Galactic open cluster. New CCD photometry and high-resolution spectroscopy are used to derive the main parameters of this cluster. At [Fe/H]=-0.11 for a single red giant star, the metallicity is slightly subsolar. The best fit to the colour-magnitude diagrams is achieved using a 1.3-Gyr isochrone with convective overshoot. The cluster appears to have a significant reddening at E(B-V)=0.46 (for B0 spectral type), although for red giants this high reddening yields the colour temperature exceeding the spectroscopic Teff by about 200K. Trumpler 20 is a very rich open cluster, containing at least 700 members brighter than M_V_=+4. It may extend over the field of view available in our study at 20x20arcmin^2^.
- ID:
- ivo://CDS.VizieR/J/A+A/417/945
- Title:
- BVI & JHK photometry of NGC 3960
- Short Name:
- J/A+A/417/945
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a BVI photometric and astrometric catalogue of the open cluster NGC 3960, down to limiting magnitude V~22, obtained from observations taken with the Wide Field Imager camera at the MPG/ESO 2.2m Telescope at La Silla. The photometry of all the stars detected in our field of view has been used to estimate a map of the strong differential reddening affecting this area. Our results indicate that, within the region where the cluster dominates, the E(V-I) values range from 0.21 up to 0.78, with E(V-I)=0.36 (E(B-V)=0.29) at the nominal cluster centroid position; color excesses E(V-I) up to 1 mag have been measured in the external regions of the field of view where field stars dominate. The reddening-corrected color-magnitude diagram (CMD) allows us to conclude that the cluster has an age between 0.9 and 1.4Gyr and a distance modulus of (V-M_V)_0=11.35. Based on observations made with the European Southern Observatory telescopes obtained from the the ESO/ST-ECF Science Archive Facility.
