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23351. UV-FIR obs. of post-starburst galaxies & dust masses
ID:
ivo://CDS.VizieR/J/ApJ/879/131
Title:
UV-FIR obs. of post-starburst galaxies & dust masses
Short Name:
J/ApJ/879/131
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive dust masses (M_dust_) from the spectral energy distributions of 58 post-starburst galaxies (PSBs). There is an anticorrelation between specific dust mass (M_dust_/M_*_) and the time elapsed since the starburst ended, indicating that dust was either destroyed, expelled, or rendered undetectable over the ~1Gyr after the burst. The M_dust_/M_*_ depletion timescale, 205_-37_^+58^Myr, is consistent with that of the CO-traced M_H2_/M_*_, suggesting that dust and gas are altered via the same process. Extrapolating these trends leads to the M_dust_/M_*_ and M_H2_/M_*_ values of early-type galaxies (ETGs) within 1-2Gyr, a timescale consistent with the evolution of other PSB properties into ETGs. Comparing Mdust and M_H2_ for PSBs yields a calibration, log M_H2_=0.45logM_dust_+6.02, that allows us to place 33 PSBs on the Kennicutt-Schmidt (KS) plane, {Sigma}SFR-{Sigma}M_H2_. Over the first ~200-300Myr, the PSBs evolve down and off of the KS relation, as their star formation rate (SFR) decreases more rapidly than M_H2_. Afterwards, M_H2_ continues to decline whereas the SFR levels off. These trends suggest that the star formation efficiency bottoms out at 10^-11^/yr and will rise to ETG levels within 0.5-1.1Gyr afterwards. The SFR decline after the burst is likely due to the absence of gas denser than the CO-traced H2. The mechanism of the M_dust_/M_*_ and M_H2_/M_*_ decline, whose timescale suggests active galactic nucleus/low-ionization nuclear emission-line region feedback, may also be preventing the large CO-traced molecular gas reservoirs from collapsing and forming denser star-forming clouds.
23352. UV-FIR SED results of SDSS QSOs and their hosts
ID:
ivo://CDS.VizieR/J/ApJ/824/70
Title:
UV-FIR SED results of SDSS QSOs and their hosts
Short Name:
J/ApJ/824/70
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this work, we present a study of 207 quasars selected from the Sloan Digital Sky Survey quasar catalogs and the Herschel Stripe 82 survey. Quasars within this sample are high-luminosity quasars with a mean bolometric luminosity of 10^46.4^erg/s. The redshift range of this sample is within z Herschel-SPIRE bands, the quasar sample is complete yet highly biased. Based on the multi-wavelength photometric observation data, we conducted a spectral energy distribution (SED) fitting through UV to FIR. Parameters such as active galactic nucleus (AGN) luminosity, far-IR (FIR) luminosity, stellar mass, as well as many other AGN and galaxy properties are deduced from the SED fitting results. The mean star formation rate (SFR) of the sample is 419M_{sun}_/yr and the mean gas mass is ~10^11.3^M_{sun}_. All of these results point to an IR luminous quasar system. Compared with star formation main sequence (MS) galaxies, at least 80 out of 207 quasars are hosted by starburst galaxies. This supports the statement that luminous AGNs are more likely to be associated with major mergers. The SFR increases with the redshift up to z=2. It is correlated with the AGN bolometric luminosity, where L_FIR_{propto}L_Bol_^0.46+/-0.03^. The AGN bolometric luminosity is also correlated with the host galaxy mass and gas mass. Yet the correlation between L_FIR_ and L_Bol_ has higher significant level, implies that the link between AGN accretion and the SFR is more primal. The M_BH_/M_*_ ratio of our sample is 0.02, higher than the value 0.005 in the local universe. It might indicate an evolutionary trend of the M_BH_/M_*_ scaling relation.
23353. UV Flux distributions of gamma Dor stars
ID:
ivo://CDS.VizieR/J/A+A/472/241
Title:
UV Flux distributions of gamma Dor stars
Short Name:
J/A+A/472/241
Date:
21 Oct 2021
Publisher:
CDS
Description:
It seems that the recently identified class of pulsating stars, the gamma Dor type-variables, includes objects with different metal abundances and a large percentage of binaries. We looked for indicators of metal abundance peculiarities and stellar binarity in a sample of 40 confirmed gamma Dor stars. Absolute magnitudes from Hipparcos parallaxes and UV magnitudes, from the S2/S68 experiment on board the TD1 satellite, are retrieved from databases and compared with predicted values. A set of non variable normal stars is used to check the consistency of this analysis and also serve as reference stars. Twenty-nine stars of the gamma Dor star sample, which is 73% of it, are discovered having abnormal UV fluxes constantly showing UV flux excesses compared to those computed with the atmospheric parameters (Teff, logg, and metallicity) determined from calibration of the uvbyBeta indices. The reason for this UV excess of flux at 196.5nm and at 236.5nm, which was previously known only for HD 209295, cannot be ascribed to binarity alone. An extra source of UV flux or less UV absorption - yet unknown - must be present.
23354. UV fluxes and electron density of AG Peg
ID:
ivo://CDS.VizieR/J/A+A/317/712
Title:
UV fluxes and electron density of AG Peg
Short Name:
J/A+A/317/712
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we study in detail the variability of the symbiotic nova AG Peg in the IUE range during the period 1978-1995. We find that the luminosity of the hot component decreased steadily from about 1850L_{sun}_ in 1978 to 430L_{sun}_ in 1995 while its effective temperature remained nearly constant, 86500+/-1300K. At the same time, the mass loss rate decreased by a factor of 4-5 although the ejection velocity remained constant. The observed fainting of both the narrow and the broad emission lines is ascribed to the decrease of the luminosity and ionizing flux from the hot source. The narrow emission lines and the long wavelength UV continuum show periodic variations arising from a dense and asymmetric nebular region associated with the cool star. Radial velocity variations of the narrow lines indicate that this region is receding from the center of mass of the system, and support the presence of the ablation tail suggested by Penston and Allen (1985MNRAS.212..939P). No periodic flux variations are seen in the short wavelength ultraviolet continuum and in the broad emission lines, which are both formed in the fast wind from the hot component.
23355. UV galaxies in CANDELS from z=8 to z=4
ID:
ivo://CDS.VizieR/J/ApJ/756/164
Title:
UV galaxies in CANDELS from z=8 to z=4
Short Name:
J/ApJ/756/164
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the evolution of galaxy rest-frame ultraviolet (UV) colors in the epoch 4<~z<~8. We use new wide-field near-infrared data in the Great Observatories Origins Deep Survey-South field from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, Hubble Ultra Deep Field (HUDF) 2009, and Early Release Science programs to select galaxies via photometric redshift measurements. Our sample consists of 2812 candidate galaxies at z>~3.5, including 113 at z=~7-8. We fit the observed spectral energy distribution to a suite of synthetic stellar population models and measure the value of the UV spectral slope ({beta}) from the best-fit model spectrum. We run simulations to show that this measurement technique results in a smaller scatter on {beta} than other methods, as well as a reduced number of galaxies with catastrophically incorrect {beta} measurements (i.e., {Delta}{beta}>1).
23356. UVILLSS Catalogue
ID:
ivo://CDS.VizieR/VI/84
Title:
UVILLSS Catalogue
Short Name:
VI/84
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue is an extension in the ultraviolet region (129 to 3903 Angstroems) of the ILLSS catalogue (Coluzzi, 1993; catalog <VI/71>) which lists lines in the optical region. The data are from "Ultraviolet Multiplet Table" (Moore 1950, 1952, 1962) and arranged in two files: the catalogue and the references. There are two versions of each file, one presented in the author's original format, and the second organised as a table. The reference files are arranged by element: for each spectrum the first line contains within parenthesis the Ionization Potential; the grade of analysis; the grade denoting the relative number of classified lines included as compared with the total number classified in the ultraviolet; the date of completion of the manuscript; the limit for three spectra H, He I, He II. The limit in cm-1 has been multiplied by the factor 0.00012345 to obtain the tabulated ionisation potential, which is expressed in electron-Volts. The analysis grades range from A to E, grade A indicating that the analysis is essentially complete ,and grade E that the structure has been recognised, but is limited to a single multiplet or transition. List A, List B, etc., denote the relative numbers of classified lines listed here as compared with the total number classified in the ultraviolet, A denoting that all classified lines in the ultraviolet are listed, and D that only a few of the leading ones are tabulated. The letters on the left, A, B, C, etc. preceding the reference, indicate the source used for the wavelength quoted in the Table. Those papers used only for analysis or intensity follow the ones used for wavelength, and are not preceded by the letters denoting the source. The letters "WL", "I", "T", indicating what was taken from each paper for the Table compilation , denote, respectively, wavelength, intensity, and terms, the last referring to the analysis of the spectrum. These informations are taken from Moore (1950).
23357. UV Images of Nearby Galaxies
ID:
ivo://CDS.VizieR/J/ApJS/107/215
Title:
UV Images of Nearby Galaxies
Short Name:
J/ApJS/107/215
Date:
21 Oct 2021
Publisher:
CDS
Description:
The accompanying tables are part of a pictorial atlas of UV (2300A) images, obtained with the Hubble Space Telescope (HST) Faint Object Camera, of the central 22"x22" of 110 galaxies. The observed galaxies are an unbiased selection constituting about one half of a complete sample of all large (D>6') and nearby (V< 2000 km/s) galaxies. This is the first extensive UV imaging survey of normal galaxies. The data are useful for studying star formation, low-level nuclear activity, and UV emission by evolved stellar populations in galaxies. At the HST resolution (0.05"), the images display an assortment of morphologies and UV brightnesses. These include bright nuclear point sources, compact young star clusters scattered in the field or arranged in circumnuclear rings, centrally-peaked diffuse light distributions, and galaxies with weak or undetected UV emission. We measure the integrated 2300A flux in each image, and classify the UV morphology. The UV and optical parameters are given in the tables.
23358. UV Interstellar Extinction
ID:
ivo://CDS.VizieR/II/114
Title:
UV Interstellar Extinction
Short Name:
II/114
Date:
21 Oct 2021
Publisher:
CDS
Description:
The documentation is mostly adapted from the "Documentation for the Machine-Readable Version of A catalog of Ultraviolet Interstellar Extinction Excesses for 1415 Stars" by Wayne H. Warren Jr., May 1986, National Space Science Data Center NSSDC/WDC-A-R&S 86-05 This document describes the machine-readable version of the catalog as it is currently being distributed from the Astronomical Data Centers. It is intended to enable users to read and process the data without problems and guesswork, but it is not intended to replace the original published paper, which users should study before processing the data. The format described below is very similar to that given on page 431 of the source reference, but some modifications were made at the ADC (with the consent of the authors) to effect uniformity.
23359. uVI photometry of 3 LMC eclipsing binaries
ID:
ivo://CDS.VizieR/J/MNRAS/349/833
Title:
uVI photometry of 3 LMC eclipsing binaries
Short Name:
J/MNRAS/349/833
Date:
21 Oct 2021
Publisher:
CDS
Description:
CCD differential photometry in the Stromgren u, Johnson V and Cousins I bands is presented of three hot, luminous eclipsing binary stars in the Magellanic Clouds. Observations were made between 1999 April and 2002 July using the McLellan Cassegrain 1-m telescope at MJUO in its f/7.7 configuration in conjunction with the CCD photometer head. The photometry has been extracted using the ISIS difference imaging method and is presented as normalized light.
23360. UV-IR photometry of SMC stars
ID:
ivo://CDS.VizieR/J/ApJ/771/13
Title:
UV-IR photometry of SMC stars
Short Name:
J/ApJ/771/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
The nature of the progenitors of Type Ia supernovae (SNe Ia) is still a mystery. While plausible candidates are known for both the single-degenerate and double-degenerate models, the observed numbers fall significantly short of what is required to reproduce the SNe Ia rate. Some of the most promising single-degenerate Type Ia progenitors are recurrent novae and super-soft sources (SSS). White dwarfs (WDs) with higher mass transfer rates can also be SN Ia progenitors. For these rapidly accreting white dwarfs (RAWDs), more material than is needed for steady burning accretes on the WD, and extends the WD's photosphere. Unlike SSS, such objects will likely not be detectable at soft X-ray energies, but will be bright at longer wavelengths, such as the far-ultraviolet (UV). Possible examples include LMC N66 and the V Sagittae stars. We present a survey using multi-object spectrographs looking for RAWDs in the central core of the Small Magellanic Cloud (SMC), from objects selected to be bright in the far-UV and with blue far UV-V colors. While we find some unusual objects, and recover known planetary nebula and Wolf-Rayet (WR) stars, we detect no candidate RAWD. The upper limits from this non-detection depend on our expectations of what an RAWD should look like, as well assumptions about the internal extinction of the SMC. Assuming they resemble LMC N66 or fainter versions of WR stars we set an upper limit of 10-14 RAWDs in the SMC. However, our survey is unlikely to detect objects like V Sge, and hence we cannot set meaningful upper limits if RAWDs generally resemble V Sge.

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