- ID:
- ivo://CDS.VizieR/J/PASP/94/244
- Title:
- UBVRI standard stars in the E-regions
- Short Name:
- J/PASP/94/244
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometry on the UBVRI Kron-Cousins system is presented for 102 stars covering the magnitude range 7 to 16 in the nine Harvard E-regions. These stars, at declination close to -45{deg}, are suitable for use as Southern Hemisphere standards in the photometry of faint stars and galaxies. The large magnitude range in most fields makes the sequences useful for the calibration of the Pickering-Racine wedge, a device widely used to extend photometric sequences to fainter limits on photographic plates. Positions accurate to a few arcseconds as well as identification charts are given for each star.
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- ID:
- ivo://CDS.VizieR/J/A+A/415/63
- Title:
- UBVRI surface brightness of 26 bright galaxies
- Short Name:
- J/A+A/415/63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The UBVRI images of 26 bright spiral galaxies were decomposed in disks and bulges. Correlations of the resulting structural parameters are investigated, giving clues to the formation history of the bulges. We confirm that the large and bright bulges of early-type spirals are similar to elliptical galaxies. They were probably formed prior to the disks in a monolithic collapse or via early mergers. Late-type spirals have tiny and faint bulges with disk-like profiles. These bulges were probably formed after the disk in secular evolution processes, e.g. from a disk instability. The comparison of the color indices of corresponding spirals and bulges with population synthesis computations support above formation scenarios.
- ID:
- ivo://CDS.VizieR/J/ApJ/885/43
- Title:
- UBVRI & ugriz photometry of supernova SN 2017gmr
- Short Name:
- J/ApJ/885/43
- Date:
- 10 Dec 2021
- Publisher:
- CDS
- Description:
- We present high-cadence UV, optical, and near-infrared data on the luminous Type II-P supernova SN2017gmr from hours after discovery through the first 180 days. SN 2017gmr does not show signs of narrow, high-ionization emission lines in the early optical spectra, yet the optical light-curve evolution suggests that an extra energy source from circumstellar medium (CSM) interaction must be present for at least 2 days after explosion. Modeling of the early light curve indicates a ~500R{sun} progenitor radius, consistent with a rather compact red supergiant, and late-time luminosities indicate that up to 0.130{+/-}0.026M{sun} of 56Ni are present, if the light curve is solely powered by radioactive decay, although the 56Ni mass may be lower if CSM interaction contributes to the post-plateau luminosity. Prominent multipeaked emission lines of H{alpha} and [O^I^] emerge after day 154, as a result of either an asymmetric explosion or asymmetries in the CSM. The lack of narrow lines within the first 2 days of explosion in the likely presence of CSM interaction may be an example of close, dense, asymmetric CSM that is quickly enveloped by the spherical supernova ejecta.
- ID:
- ivo://CDS.VizieR/J/AJ/126/632
- Title:
- UBVRIz'HK' photometry of 2Ms CDFN X-ray sources
- Short Name:
- J/AJ/126/632
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical and near-infrared catalog for the X-ray sources in the 2Ms Chandra observation of the Hubble Deep Field North region. We have high-quality multicolor imaging data for all 503 X-ray point sources in the X-ray-selected catalog and reliable spectroscopic redshifts for 284. We spectroscopically identify six high-redshift (z>1) type II quasars (L_2-8keV_>10^44^ergs/s) in our sample. Our spectroscopic completeness for the R<=24 sources is 87%. The spectroscopic redshift distribution shows two broad redshift spikes that have clearly grown over those originally seen in the 1Ms exposure. The spectroscopically identified extragalactic sources already comprise 75% of the measured 2-8keV light. Redshift slices versus 2-8keV flux show that an impressive 54% of the measured 2-8keV light arises from sources at z<1 and 68% from sources at z<2.
- ID:
- ivo://CDS.VizieR/J/AJ/151/33
- Title:
- UBVRIz light curves of 51 Type II supernovae
- Short Name:
- J/AJ/151/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a compilation of UBVRIz light curves of 51 type II supernovae discovered during the course of four different surveys during 1986-2003: the Cerro Tololo Supernova Survey, the Calan/Tololo Supernova Program (C&T), the Supernova Optical and Infrared Survey (SOIRS), and the Carnegie Type II Supernova Survey (CATS). The photometry is based on template-subtracted images to eliminate any potential host galaxy light contamination, and calibrated from foreground stars. This work presents these photometric data, studies the color evolution using different bands, and explores the relation between the magnitude at maximum brightness and the brightness decline parameter (s) from maximum light through the end of the recombination phase. This parameter is found to be shallower for redder bands and appears to have the best correlation in the B band. In addition, it also correlates with the plateau duration, being shorter (longer) for larger (smaller) s values.
- ID:
- ivo://CDS.VizieR/J/AN/323/31
- Title:
- UBVR light curves of ER Vul and RT And
- Short Name:
- J/AN/323/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the light curves of chromospherically active binary systems, RT And and ER Vul, obtained during 1995-1998 in BV/UBVR filters at the Ankara University Observatory and the TUBITAK National Observatory. In addition, the spot distributions for these systems are investigated by using the Wilson-Devinney program. Outside of the eclipses, the light curve variations are attributed to large cool spots located on one of components of the systems. While three spots were located on the primary component in the case of RT And, the location of three spots were considered on the secondary star in the case of ER Vul. From the spot motions in longitudes between 1995 and 1998, it was inferred that the migration period of the distortion wave has at value of 6.6 years for RT And.
- ID:
- ivo://CDS.VizieR/J/AZh/86/158
- Title:
- UBVR light curves of GSC 4596-1254 = SAO 3282
- Short Name:
- J/AZh/86/158
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained the first UBVR photoelectric light curves for a recently discovered eclipsing binary with a period of 9.33d and an appreciable eccentricity (e=0.08). We have used these data to determine the photometric elements of the system for a model with two spherical stars with linear limb darkening. The high accuracy of the observations enabled determination of the absolute parameters of the components using available calibrations. The masses of the components are 1.28 and 1.08M_{sun}_, and their ages are two billion years. The present orientation of the orbital ellipse is unfavorable for studies of the apsidal rotation, which is essentially due to relativistic effects.
- ID:
- ivo://CDS.VizieR/J/A+A/479/827
- Title:
- UBVR light curves of weak-line T Tauri stars
- Short Name:
- J/A+A/479/827
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- T Tauri stars exhibit variability on all timescales, whose origin is still debated. On WTTS the variability is fairly simple and attributed to long-lived, ubiquitous cool spots. We investigate the long term variability of WTTS, extending up to 20 years in some cases, characterize it statistically and discuss its implications for our understanding of these stars. We have obtained a unique, homogeneous database of photometric measurements for WTTS extending up to 20-years. It contains more than 9000 UBVR observations of 48 WTTS. All the data were collected at Mount Maidanak Observatory (Uzbekistan) and they constitute the longest homogeneous record of accurate WTTS photometry ever assembled. Definitive rotation periods for 35 of the 48 stars are obtained. Phased light curves over 5 to 20 seasons are now available for analysis. Light curve shapes, amplitudes and colour variations are obtained for this sample and various behaviors exhibited, discussed and interpreted. Our main conclusion is that most WTTS have very stable long term variability with relatively small changes of amplitude or mean light level. The long term variability seen reflects modulation in the cold spot distributions. Photometric periods are stable over many years, and the phase of minimum light can be stable as well for several years. On the long term, spot properties do change in subtle ways, leading to secular variations in the shape and amplitudes of the light curves.
- ID:
- ivo://CDS.VizieR/J/ApJ/630/784
- Title:
- UBVR observations of nearby galaxies
- Short Name:
- J/ApJ/630/784
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We introduce a data set of 142 mostly late-type spiral, irregular, and peculiar (interacting or merging) nearby galaxies observed in UBVR at the Vatican Advanced Technology Telescope (VATT), and we present an analysis of their radial color gradients.
- ID:
- ivo://CDS.VizieR/J/AN/316/225
- Title:
- UBVR photoelectric survey
- Short Name:
- J/AN/316/225
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalogue of photoelectric stellar magnitudes and colours in the UBVR Johnson system in 47 sky areas with galaxies near the Main Galactic Meridian is presented. The catalogue includes 1141 stars within the V magnitude interval 4.5-15.5mag. The rms errors are +/-0.014, +/-0.026, +/-0.012, +/-0.016mag for stellar magnitudes V and colours (U-B), (B-V), (V-R), respectively. The catalogue contains accurate equatorial coordinates (alpha, delta)_1950.0_, too.
