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16501. UV mag of candidate galaxies at 3~<z~<8.5
ID:
ivo://CDS.VizieR/J/ApJ/810/71
Title:
UV mag of candidate galaxies at 3~<z~<8.5
Short Name:
J/ApJ/810/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a robust measurement and analysis of the rest-frame ultraviolet (UV) luminosity functions at z=4-8. We use deep Hubble Space Telescope imaging over the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey/GOODS fields, the Hubble Ultra Deep Field, and the Hubble Frontier Field deep parallel observations near the Abell 2744 and MACS J0416.1-2403 clusters. The combination of these surveys provides an effective volume of 0.6-1.2x10^6^Mpc^3^ over this epoch, allowing us to perform a robust search for faint (M_UV_=-18) and bright (M_UV_<-21) high-redshift galaxies. We select candidate galaxies using a well-tested photometric redshift technique with careful screening of contaminants, finding a sample of 7446 candidate galaxies at 3.5<z<8.5, with >1000 galaxies at z~6-8. We measure both a stepwise luminosity function for candidate galaxies in our redshift samples, and a Schechter function, using a Markov Chain Monte Carlo analysis to measure robust uncertainties. At the faint end, our UV luminosity functions agree with previous studies, yet we find a higher abundance of UV-bright candidate galaxies at z>=6.
16502. UV Observations of the SMC
ID:
ivo://CDS.VizieR/J/AJ/113/1011
Title:
UV Observations of the SMC
Short Name:
J/AJ/113/1011
Date:
21 Oct 2021
Publisher:
CDS
Description:
A mosaic of four UIT (Ultraviolet Imaging Telescope) far-UV (FUV) ({lambda}_(eff)_=1620{AA}) images, with derived stellar and H II region photometry, is presented for most of the Bar of the SMC. The UV morphology of the SMC's Bar shows that recent star formation there has left striking features including: (a) four concentrations of UV-bright stars spread from northeast to southwest at nearly equal (~30arcmin=0.5kpc) spacings; (b) one of the concentrations, near DEM 55, comprises a well-defined 8-arcmin diameter ring surrounded by a larger H{alpha} ring, suggestive of sequential star formation. FUV PSF photometry is obtained for 11,306 stars in the FUV images, resulting in magnitudes m(162). We present a FUV luminosity function for the SMC Bar, complete to m(162)~14.5. Detected objects are well correlated with other SMC Population I material; of 711 H{alpha} emission-line stars and small nebulae within the UIT fields of view, 520 are identified with FUV sources. The FUV photometry is compared with available ground-based catalogs of supergiants, yielding 191 detections of 195 supergiants with spectral type earlier than F0 in the UIT fields. The (m(162)-V) color for supergiants is a sensitive measure of spectral type. The bluest observed colors for each type agree well with colors computed from unreddened Galactic spectral atlas stars for types earlier than about A0; for later spectral types the observed SMC stars range significantly bluer, as predicted by comparison of low-metallicity and Galactic-composition models. Redder colors for some stars of all spectral types are attributed to the strong FUV extinction arising from even small amounts of SMC dust. Internal SMC reddenings are determined for all catalog stars. All stars with E(B-V)>0.15 are within regions of visible H{alpha} emission. FUV photometry for 42 H{alpha} -selected H II regions in the SMC Bar is obtained for stars and for total emission (as measured in H II-region-sized apertures). The flux-weighted average ratio of total to stellar FUV flux is 2.15; consideration of the stellar FUV luminosity function indicates that most of the excess total flux is due to scattered FUV radiation, rather than stars fainter than m(162)=14.5. Both stellar and total emission are well correlated with H{alpha} fluxes measured by Kennicutt and Hodge (1986ApJ...306..130K), yielding FUV/H{alpha} flux ratios that are consistent with models of SMC metallicity, ages from 1-5Myr, and moderate (E(B-V)=0.0-0.1mag) internal SMC extinction. (Copyright) 1997 American Astronomical Society.
16503. UV/Optical/NIR spectroscopy GRB hosts
ID:
ivo://CDS.VizieR/J/A+A/581/A125
Title:
UV/Optical/NIR spectroscopy GRB hosts
Short Name:
J/A+A/581/A125
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present data and initial results from VLT/X-shooter emission-line spectroscopy of 96 galaxies selected by long gamma-ray bursts (GRBs) at 0.1<z<3.6, the largest sample of GRB host spectra available to date. Most of our GRBs were detected by Swift and 76% are at 0.5<z<2.5 with a median z_med_~1.6.
16504. UVOT Bright Star Catalog
ID:
ivo://nasa.heasarc/uvotbscat
Title:
UVOT Bright Star Catalog
Short Name:
UVOTBSCAT
Date:
28 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This catalog was compiled from 4 catalogs: Tycho-2, GVCS III, NGC, and the Yale Bright Star Catalog. All catalogs were preprocessed before compiling this catalog to achieve uniform columns and units. Next, they were merged into one catalogue before eliminating &quot;red&quot; objects and precessing all coordinates to epoch 2000.0. The catalog was then corrected for missing decimal points. Finally, the catalog was sorted by R.A. for ease of locating objects within the catalogue. The original catalog contained 239,853 objects brighter than 12.0 mags. This table was originally created by the HEASARC in July 2008 based on an input table supplied by the Swift Project which was compiled by Elizabeth Auden at MSSL. It was renamed to UVOTBSCAT in January 2009. This is a service provided by NASA HEASARC .
16505. UVOT imaging of M81 and Holmberg IX
ID:
ivo://CDS.VizieR/J/AJ/141/205
Title:
UVOT imaging of M81 and Holmberg IX
Short Name:
J/AJ/141/205
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Swift UV/Optical Telescope (UVOT) imaging of the galaxies M81 and Holmberg IX. We combine UVOT imaging in three near-ultraviolet (NUV) filters (uvw2: 1928{AA}; uvm2: 2246{AA}; uvw1: 2600{AA}) with ground-based optical imaging from the Sloan Digital Sky Survey to constrain the stellar populations of both galaxies. Our analysis consists of three different methods. First, we use the NUV imaging to identify UV star-forming knots and then perform spectral energy distribution (SED) modeling on the UV/optical photometry of these sources. Second, we measure surface brightness profiles of the disk of M81 in the NUV and optical. Lastly, we use SED fitting of individual pixels to map the properties of the two galaxies.
16506. UVOT light curves of supernovae
ID:
ivo://CDS.VizieR/J/AJ/137/4517
Title:
UVOT light curves of supernovae
Short Name:
J/AJ/137/4517
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present ultraviolet (UV) observations of supernovae (SNe) obtained with the UltraViolet/Optical Telescope (UVOT) on board the Swift spacecraft. This is the largest sample of UV light curves from any single instrument and covers all major SN types and most subtypes.
16507. UVOT photometry of Super-Chandrasekhar mass SNe Ia
ID:
ivo://CDS.VizieR/J/ApJ/787/29
Title:
UVOT photometry of Super-Chandrasekhar mass SNe Ia
Short Name:
J/ApJ/787/29
Date:
21 Oct 2021
Publisher:
CDS
Description:
Among Type Ia supernovae (SNe Ia), a class of overluminous objects exist whose ejecta mass is inferred to be larger than the canonical Chandrasekhar mass. We present and discuss the UV/optical photometric light curves, colors, absolute magnitudes, and spectra of three candidate Super-Chandrasekhar mass SNe - 2009dc, 2011aa, and 2012dn - observed with the Swift Ultraviolet/Optical Telescope. The light curves are at the broad end for SNe Ia, with the light curves of SN 2011aa being among the broadest ever observed. We find all three to have very blue colors which may provide a means of excluding these overluminous SNe from cosmological analysis, though there is some overlap with the bluest of "normal" SNe Ia. All three are overluminous in their UV absolute magnitudes compared to normal and broad SNe Ia, but SNe 2011aa and 2012dn are not optically overluminous compared to normal SNe Ia. The integrated luminosity curves of SNe 2011aa and 2012dn in the UVOT range (1600-6000 {AA}) are only half as bright as SN 2009dc, implying a smaller ^56^Ni yield. While it is not enough to strongly affect the bolometric flux, the early time mid-UV flux makes a significant contribution at early times. The strong spectral features in the mid-UV spectra of SNe 2009dc and 2012dn suggest a higher temperature and lower opacity to be the cause of the UV excess rather than a hot, smooth blackbody from shock interaction. Further work is needed to determine the ejecta and ^56^Ni masses of SNe 2011aa and 2012dn and to fully explain their high UV luminosities.
16508. UV photometry in M79
ID:
ivo://CDS.VizieR/J/AJ/112/601
Title:
UV photometry in M79
Short Name:
J/AJ/112/601
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ultraviolet photometry is presented for the globular cluster M79 (NGC 1904) according to the final calibration of the images obtained on the Astro-1 Spacelab mission by the Ultraviolet Imaging Telescope. These results include both point-source and surface photometry at 152nm and 249nm. An ultraviolet color-magnitude (C-M) diagram in these bandpasses is presented. The detected stars are also cross-matched with the ground-based photometry of Ferraro et al. (1992MNRAS.256..391F) to produce C-M and two-color diagrams covering a 4000A span in wavelength. The observed horizontal branch (HB) is compared with stellar interior models of the zero-age HB (ZAHB). Many stars are found in post-HB evolutionary stages more luminous than the ZAHB. The distribution of stars along the ZAHB in m152-m249 color is investigated, and an indication of possible bimodality is found. The relative population of the blue HB tail may vary with radius for radii greater than 1'. Ultraviolet surface brightness and color-index profiles are presented. The previously reported central gradient in the m152-V color index is confirmed, and a faint diffuse component is detected outside a radius of 40" in the 152nm band. Two possible causes of the central color gradient are discussed: mass segregation, and the destruction of red giant envelopes by enhanced mass loss in the cluster core.
16509. U,V photometry in M2 (NGC 7089)
ID:
ivo://CDS.VizieR/J/A+A/548/A107
Title:
U,V photometry in M2 (NGC 7089)
Short Name:
J/A+A/548/A107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present U, V photometry of the globular cluster M2. Stars within 1' and outside of 4' from the cluster center are excluded from the CMD to reduce blending effects and the field star contamination, respectively. We imposed on all stars the selection limits of CHI<2.0 and -1<SHARP<1 on DAOPHOT II photometric parameters. To select a sample of well-measured stars we have followed the procedure given in Lardo et al. (2012A&A...541A.141L), Sect. 5.1. M2 photometry displays an anomalous branch beyond the red edge of the main body of the RGB. The difference in color between stars belonging to this structure and normal RGB stars is quite large (of the order of 0.2-0.3mag, well above the typical measurement errors) and extends down to the SGB region. There may be a second group of stars that are 0.3mag redder with respect to this sequence and can possibly be more, anomalous RGB stars. The observations were carried out during the nights of 2010 July 15 at the Telescopio Nazionale Galileo (TNG) located in La Palma, Canary Islands (Spain), with he DOLORES camera. The DOLORES camera offers a field of view of 8.6'x8.6' with a 0.252"/pix scale. We obtained images of the cluster in the standard Johnson U and V filters for a total of 540s shifted in 3 single exposures in each filter. The seeing condition were average during (~1.2-1.3") during the observing night.
16510. UV photometry in NGC 2808
ID:
ivo://CDS.VizieR/J/ApJ/562/368
Title:
UV photometry in NGC 2808
Short Name:
J/ApJ/562/368
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine new observations of NGC 2808, taken with the far-UV and near-UV cameras on the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). Images were obtained in the far-UV crystal quartz (FUV/F25QTZ; pivot wavelength 1600{AA}), near-UV 2700{AA} continuum (NUV/F25CN270), and clear CCD (CCD/50CCD; pivot wavelength 5850{AA}) modes, employing a cross-shaped dither pattern.

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