- ID:
- ivo://CDS.VizieR/II/118
- Title:
- UBVRI standards around Celestial Equator
- Short Name:
- II/118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains UBVRI photoelectric observations of 223 stars, mostly in an approximately 2-degree zone centered on the celestial equator. The catalog is intended to provide a uniform set of new standards, available to various sizes of telescopes in both hemispheres, on an internally consistent, homogeneous system. Most of the stars are in Selected Areas 92-115 and fall in the magnitude range of about 7 to 12.5 in V and color range -0.3 to +2.0 in B-V. The data include equatorial coordinates, photoelectric magnitudes and colors, numbers of observations, and computed internal errors. See the complete description by Wayne H. Warren Jr., either in plain ascii (file adc.doc) or in LaTeX format (file adc.tex)
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- ID:
- ivo://CDS.VizieR/J/AJ/133/2502
- Title:
- UBVRI Standard Stars
- Short Name:
- J/AJ/133/2502
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- UBVRI photoelectric observations have been made of 109 stars around the sky, centered more or less at -50{deg} declination. The majority of the stars fall in the magnitude range 10.4<V<15.5 and in the color index range -0.33<(B-V)<+1.66. These new broadband photometric standard stars average 16.4 measurements each from data taken on 116 different nights over a period of 4yr. Similar data are tabulated for 19 stars of interest that were not observed often enough to make them well-defined standard stars.
- ID:
- ivo://CDS.VizieR/J/AJ/146/88
- Title:
- UBVRI standard stars around the celestial equator
- Short Name:
- J/AJ/146/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-quality CCD-based UBVRI photometry is presented for ~45000 stars distributed among 60 different fields centered on the celestial equator and at {delta}{approx}-50{deg}. This photometry has been calibrated to the standard Johnson UBV and Kron-Cousins RI systems via observations of the UBVRI standard stars presented in the works of Landolt. The majority of the stars in our photometric catalog fall in the magnitude range 12<~V<~22 and in the color range -0.3<~(B-V)<~1.8. Each star averages 67 measures in each UBVRI filter from data taken on 250 different photometric nights over a period of ~6.5yr from two different telescopes. Our final photometric database effectively extends the UBVRI standard star network defined by Landolt to much fainter magnitudes and increases the number density of stars within pre-existing standard fields. Hence, these new, fainter standards serve as suitable calibrators for investigators who employ either small or large-aperture telescopes for their observational projects.
- ID:
- ivo://CDS.VizieR/J/AJ/146/131
- Title:
- UBVRI standard stars at +50{deg} declination
- Short Name:
- J/AJ/146/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- UBVRI photoelectric observations have been made of 335 stars around the sky, and centered approximately at +50{deg} declination. The majority of the stars fall in the magnitude range 9<V<16, and in the color range -0.3<(B-V)<+1.8. Those 243 stars best suited as new broadband photometric standard stars average 12.5 measures each from data taken on 98 different nights over a period of 17 years at the Kitt Peak National and Lowell Observatories.
- 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.
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/3028
- Title:
- UVIT and GALEX count rates
- Short Name:
- J/MNRAS/471/3028
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have studied the performance of the Ultraviolet Imaging Telescope payload on AstroSat and derived a calibration of the far-ultraviolet (FUV) and near-ultraviolet (NUV) instruments on board. We find that the sensitivity of both the FUV and NUV channels is as expected from ground calibrations, with the FUV effective area about 35 per cent and the NUV effective area about the same as that of GALEX. The point spread function of the instrument is on the order of 1.2-1.6''. We have found that pixel-to-pixel variations in the sensitivity are less than 10 per cent with spacecraft motion compensating for most of the flat-field variations. We derived a distortion correction but recommend that it be applied post-processing as part of an astrometric solution.
- ID:
- ivo://CDS.VizieR/J/ApJ/669/525
- Title:
- VRI photometric standards for NGC 6946
- Short Name:
- J/ApJ/669/525
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new, very late time optical photometry and spectroscopy of the interesting Type II-P supernova SN 2002hh, in NGC 6946. Gemini/GMOS-N has been used to acquire visible spectra at six epochs between 2004 August and 2006 July, following the evolution of the SN from age 661 to 1358-days. Few optical spectra of Type II supernovae with ages greater than 1yr exist. In addition, g', r', and i' images were acquired at all six epochs. The spectral and photometric evolution of SN 2002hh has been very unusual. Measures of the brightness of this SN, both in the R and I bands, as well as in the Halpha emission flux, show no significant fading over an interval of nearly 2-years.
- ID:
- ivo://CDS.VizieR/J/A+A/634/A133
- Title:
- X-Shooter Spectral Library (XSL). DR2
- Short Name:
- J/A+A/634/A133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the second data release (DR2) of the X-Shooter Spectral Library (XSL), which contains all the spectra obtained over the six semesters of that program. This release supersedes our first data release from 2014, with a larger number of spectra (813 observations of 666 stars) and with a more extended wavelength coverage as the data from the near-infrared arm of the X-Shooter spectrograph are now included. The DR2 spectra then consist of three segments that were observed simultaneously and, if combined, cover the range between 300nm and 2.45um at a spectral resolving power close to R=10000. The spectra were corrected for instrument transmission and telluric absorption, and they were also corrected for wavelength-dependent flux-losses in 85% of the cases. On average, synthesized broad-band colors agree with those of the MILES library and of the combined IRTF and Extended IRTF libraries to within 1%. The scatter in these comparisons indicates typical errors on individual colors in the XSL of 2-4%. The comparison with 2MASS point source photometry shows systematics of up to 5% in some colors, which we attribute mostly to zero-point or transmission curve errors and a scatter that is consistent with the above uncertainty estimates. The final spectra were corrected for radial velocity and are provided in the rest-frame (with wavelengths in air). The spectra cover a large range of spectral types and chemical compositions (with an emphasis on the red giant branch), which makes this library an asset when creating stellar population synthesis models or for the validation of near-ultraviolet to near-infrared theoretical stellar spectra across the Hertzsprung-Russell diagram.
- ID:
- ivo://CDS.VizieR/J/A+A/565/A117
- Title:
- X-Shooter Spectral Library (XSL). DR1
- Short Name:
- J/A+A/565/A117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first release of XSL, the X-Shooter Spectral Library observed at the European Southern Observatory (ESO). This release contains 237 stars spanning the wavelengths 3000-10200{AA} observed at a resolving power R~10000. Telluric standard stars used to correct the Earth atmospheric contamination are presented as well.
