- ID:
- ivo://CDS.VizieR/J/MNRAS/448/2608
- Title:
- UV and optical photometric data for SN 2013by
- Short Name:
- J/MNRAS/448/2608
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multiband ultraviolet and optical light curves, as well as visual-wavelength and near-infrared spectroscopy of the Type II linear (IIL) supernova (SN) 2013by. We show that SN 2013by and other SNe IIL in the literature, after their linear decline phase that start after maximum, have a sharp light-curve decline similar to that seen in SNe IIP. This light-curve feature has rarely been observed in other SNe IIL due to their relative rarity and the intrinsic faintness of this particular phase of the light curve. We suggest that the presence of this drop could be used as a physical parameter to distinguish between subclasses of SNe II, rather than their light-curve decline rate shortly after peak. Close inspection of the spectra of SN 2013by indicate asymmetric line profiles and signatures of high-velocity hydrogen. Late (~90d after explosion) near-infrared spectra of SN 2013by exhibit oxygen lines, indicating significant mixing within the ejecta. From the late-time light curve, we estimate that 0.029 M_{sun}_ of ^56^Ni was synthesized during the explosion. It is also shown that the V-band light-curve slope is responsible for part of the scatter in the luminosity (V magnitude 50d after explosion) versus ^56^Ni relation. Our observations of SN 2013by and other SNe IIL through the onset of the nebular phase indicate that their progenitors are similar to those of SNe IIP.
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- ID:
- ivo://CDS.VizieR/J/AJ/126/1208
- Title:
- UVBI magnitudes and redshifts in HDF-South
- Short Name:
- J/AJ/126/1208
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 97 (*) spectroscopic redshifts of z<1 galaxies in the Hubble Deep Field South (HDF-S) and its flanking fields (FFs). In the HDF-S proper we observed approximately half the galaxies brighter than I_814_(AB)=24 and obtained redshifts for 76% of them. Targets in our HDF-S sample were preselected to be at z<1 based on photometric redshifts, while in the FFs a simple magnitude cut was used. The photometric redshift preselection in the HDF-S resulted in a spectroscopic success rate that is significantly higher than in the FFs, where no preselection was applied. The rms precision of our redshift measurements, determined from repeat observations, is {delta}z=0.0003. We present the photometry and redshifts for the 97 objects for which we secured spectroscopic redshifts and describe the basic properties of this sample. The photometry was derived from the HST observations; the spectroscopy was obtained at the VLT using the FORS2 spectrograph on the Kueyen (UT2) and Yepun (UT4) 8.2m telescopes. (*) Actually, 103 redshifts in table1.
- ID:
- ivo://CDS.VizieR/J/ApJ/469/629
- Title:
- UV-brightest stars of M33 and its nucleus
- Short Name:
- J/ApJ/469/629
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the UV-brightest sources in the nearby galaxy M33. Our catalog of 356 sources is constructed from far-ultraviolet (FUV; 1500A) and near-ultraviolet (NUV; 2400A) images obtained with the Ultraviolet Imaging Telescope (UIT) matched with ground-based UBV data. We find that our survey is limited by the FUV flux and is complete to F_1500=2.5x10^-15ergs/cm^2^/s/A, other than in the most crowded regions; this corresponds roughly to Mbol=-9.2 to -10.0 (or masses of 40-60M_{sun}_), for Teff=50,000{deg} to 10,000{deg}. We use Hubble Space Telescope (HST) WFPC2 images of several M33 fields to conclude that at least one-half of our sample is uncontaminated by unresolved neighbors, at least at the 0.1" (0.4pc) level, a resolution similar to that achieved in the LMC from the ground. Spectral types have been obtained for 131 of our objects. We discuss the spatial distribution of the UIT sources, finding that they provide an excellent tracer of the spiral arm pattern and confirm that star formation continues in the nuclear region to the present day. Our survey has found a large number of O and early B-type supergiants, including stars as early as O6, but the optical spectroscopic sample is dominated by later type B supergiants, as these are the visually brighter. Among the brightest stars (both at 1500A and at V) are the "superluminous" Wolf-Rayet stars first discovered by Conti & Massey in the largest H II regions of M33; these objects are now known to be small groups of stars in modest analog to R136 in 30 Dor. In general, our survey has failed to detect the known W-R stars, as they are too faint, but we did find several new late-type WN stars and composite systems, which are brighter. Two stars of high absolute visual magnitude (M_v~-9.0) are found to be B I + WN binaries, similar to HDE 269546 in the LMC; one of these is multiple at HST resolution. Most interesting, perhaps, is our finding six Ofpe/WN9 "slash" stars, five of them newly discovered. These stars show properties intermediate between those of Of and WN stars and are believed to be a quiescent form of luminous blue variables (LBVs). Our spectroscopy found five additional stars that are spectroscopically similar to the known LBVs of M33. One of these stars has recently been shown to be spectroscopically variable, and we suggest that all of these stars deserve continued scrutiny. The nucleus of M33 is the visually brightest object in our survey, and its UV colors are indicative of a hotter component than its optical photometry or spectral type would suggest. We discuss the possibility that the pointlike nucleus may contain a few interesting hot stars that dominate the light in the UV, and we make the comparison to the cluster of He I emission-line stars found near the center of the Milky Way. We comment on which color-magnitude and color-color plots make the best diagnostic tools for studying the hot, massive star population of a galaxy like M33.
- ID:
- ivo://CDS.VizieR/J/A+A/415/273
- Title:
- UVBRI photometry and spectroscopy of AG Dra
- Short Name:
- J/A+A/415/273
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric UBVri observations of the symbiotic star AG Dra in Piwnice Observatory, Torun, Poland, are presented in tables 2 and 3. The 60cm telescope and a single-channel photoelectric photometer have been used. Table 2 lists observations with the EMI9558B photomultiplier tube from March 1996 to September 1999. Table 3 lists observations with the cooled C31034 photomultiplier tube from October 2001 to May 2003. Table 4 lists equivalent widths (EW) of the four emission lines in the spectrum of AG Dra: The Raman scattered line at 6825{AA}, H{alpha}, H{beta} and He II 4686{AA}. The spectroscopic observations have been performed in Tartu Observatory, Estonia, using the 1.5m telescope and a Cassegrain spectrograph. The time interval extends from September 1997 to March 2003.
- ID:
- ivo://CDS.VizieR/J/A+AS/103/183
- Title:
- UVBRI photometry of FK Com
- Short Name:
- J/A+AS/103/183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
4306. uvby-beta Catalogue
- ID:
- ivo://CDS.VizieR/II/215
- Title:
- uvby-beta Catalogue
- Short Name:
- II/215
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is an updated version of the one published in 1990 (Hauck and Mermilliod, 1990) and contains data for more than 63,300 stars in the Galaxy and Magellanic Clouds. In a first table, we present the catalogue itself, giving for each star identifications, coordinates (B1950), visual magnitude, and the mean value of the photoelectric data concerning the star and the data sources. In the second table, we give for each star, the individual measurements. These measurements from which these values were computed were collected from observations published until the middle of 1996. The catalogue includes 533 references.
- ID:
- ivo://CDS.VizieR/J/A+AS/122/559
- Title:
- uvby-beta CCD photometry secondary standard
- Short Name:
- J/A+AS/122/559
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate standard uvby indices are presented for 73 southern B, A, F and G stars in the V magnitude range 8.2 to 10.9. They cover all three transformation regions of the uvby system (Olsen 1983A&AS...54...55O) well. Standard {beta} indices are included for the 55 B, A, and F stars in the sample. Our results provide a useful set of secondary standards for uvby {beta} CCD photometry with southern hemisphere 1-2m class telescopes. A critical comparison with published photometry, in general based on fewer observations, is given.
- ID:
- ivo://CDS.VizieR/J/A+AS/92/841
- Title:
- uvby-beta observations of 528 B stars
- Short Name:
- J/A+AS/92/841
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/II/78
- Title:
- uvby-Beta Phot 398 Members of Visual Multiple Systems
- Short Name:
- II/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue contains mainly two types of visual double stars: Evolved stars with main sequence companions; and systems, for which the IDS gives photometric and spectroscopic data, that suggest the secondary to be above the main sequence if the primary is placed on the main sequence. The photometry has been done with the Danish 50 cm reflector on La Silla, ESO, the limiting magnitude is 12m, separations are larger than 7". Identifications given are IDS, HD, and DM numbers. For each object V, b-y, ml, cl, and beta are given together with the number of nights, weights and r.m.s. errors of one observation (weight 1). The catalogue is published as table IV by E.H. Olsen, Astron. Astrophys. Suppl. 48, 165, where further details and discussion may be found.
- ID:
- ivo://CDS.VizieR/J/A+A/549/A78
- Title:
- uvby{beta} photometric catalog toward Anticenter
- Short Name:
- J/A+A/549/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A uvbyH{beta} Stromgren photometric survey covering 16sq.deg in the anticenter direction was carried out using the Wide Field Camera (WFC) at the Isaac Newton Telescope (INT), with a typical seeing of 1-1.5". Data from three different observing runs (2009A, 2010B, 2011A) were used for the catalog. The calibration to the standard system was undertaken using open clusters. A main catalog of 35974 stars with all Stromgren indexes, and a more extended one with 96980 stars with partial data. The central 8sq.deg have a limiting magnitude of V=17mag while the outer region reaches V=15.5mag. Two catalogs are available, the first one with the final mean values and a second one with all the individual measurements for each star.
