- ID:
- ivo://CDS.VizieR/VI/103
- Title:
- The Hopkins Ultraviolet Telescope (HUT)
- Short Name:
- VI/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hopkins Ultraviolet Telescope HUT was one of three ultraviolet instruments of the ASTRO-1 mission flown on the space shuttle Columbia during 2-10 December 1990. 106 spectrophotometric observations of 77 targets were obtained in the far-UV (i.e., 912-1850{AA}) at a resolution of ~3{AA}. A few sources were observed in the 415-912{AA} region with a 1.5{AA} resolution. The same three instruments were later flown on the space shuttle Endeavour from 3-17 March 1995 as part of the ASTRO-2 mission. During the longer ASTRO-2 mission, 385 observations of 265 targets were obtained.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/373/730
- Title:
- The IUE Absolute Flux Scale
- Short Name:
- J/A+A/373/730
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Tables tablea1 to tablea6 show the absolute fluxes of the IUE standard stars used for the derivation of the cameras Inverse Sensitivity Curves for the IUE Final Archive. The relative fluxes of the standard stars have been derived with the WD model, and the zero point of the scale has been set by OAO-2 observations. These fluxes define the absolute flux scale of IUE. Table tableb1 contains the model fluxes of the White Dwarf G191 B2B scaled to the OAO-2 flux scale.
- ID:
- ivo://CDS.VizieR/J/PASP/106/745
- Title:
- The Spectrum of IC 418
- Short Name:
- J/PASP/106/745
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A detailed high spectral resolution study of the spectrum of IC 418 is made for the region 3650{AA} to 10050{AA}, using the Hamilton echelle spectrograph of Lick Observatory, and of the UV spectral region with archival International Ultraviolet Explorer (IUE) data.
- ID:
- ivo://CDS.VizieR/J/ApJ/741/79
- Title:
- The Spitzer-SDSS-GALEX Spectroscopic Survey
- Short Name:
- J/ApJ/741/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer-SDSS-GALEX Spectroscopic Survey (SSGSS) provides a new sample of 101 star-forming galaxies at z<0.2 with unprecedented multi-wavelength coverage. New mid- to far-infrared spectroscopy from the Spitzer Space Telescope is added to a rich suite of previous imaging and spectroscopy, including ROSAT, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, and Spitzer/SWIRE. Sample selection ensures an even coverage of the full range of normal galaxy properties, spanning two orders of magnitude in stellar mass, color, and dust attenuation. In this paper we present the SSGSS data set, describe the science drivers, and detail the sample selection, observations, data reduction, and quality assessment.
- ID:
- ivo://CDS.VizieR/VI/104
- Title:
- The Ultraviolet Imaging Telescope (UIT)
- Short Name:
- VI/104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- UIT was one of three ultraviolet telescopes on the ASTRO-1 mission flown on the space shuttle Columbia during 2-10 December 1990. The same three instruments were later flown on the space shuttle Endeavour during 3-17 March 1995, as part of the ASTRO-2 mission. Exposures were obtained on 70-mm photographic film in the 1200-3300 Angstrom range using broadband filters and later digitized using a Perkin-Elmer microdensitometer. Image resolution was 3 arcseconds over a 40 minute field of view. Overall, UIT-1 obtained 821 exposures of 66 targets, and UIT-2 obtained 758 images of 193 targets.
- ID:
- ivo://CDS.VizieR/J/ApJ/759/112
- Title:
- The UV low-redshift intergalactic medium
- Short Name:
- J/ApJ/759/112
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive catalog of ultraviolet (HST/STIS and FUSE) absorbers in the low-redshift intergalactic medium (IGM) at z<0.4. The catalog draws from much of the extensive literature on IGM absorption and reconciles discrepancies among several previous catalogs through a critical evaluation of all reported absorption features in light of new HST/COS data. We report on 746 H I absorbers down to a rest-frame equivalent width of 12m{AA} over a maximum redshift path length {Delta}z=5.38. We also confirm 111 O VI absorbers, 29 C IV absorbers, and numerous absorption lines due to other metal ions. We characterize the bivariate distribution of absorbers in redshift and column density as a power law, ({partial}^2^N/{partial}z{partial}N){propto}N^-{beta}^, where {beta}=2.08+/-0.12 for O VI and {beta}=1.68+/-0.03 for H I. Utilizing a more sophisticated accounting technique than past work, our catalog accounts for ~43% of the baryons: 24+/-2% in the photoionized Ly{alpha} forest and 19+/-2% in the warm-hot IGM as traced by O VI. We discuss the large systematic effects of various assumed metallicities and ionization states on these calculations, and we implement recent simulation results in our estimates.
- ID:
- ivo://CDS.VizieR/J/AJ/127/2915
- Title:
- Triple systems (cool primary + hot binary)
- Short Name:
- J/AJ/127/2915
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the course of comparing parameters of evolved cool star plus hot main-sequence star binaries with theoretical isochrones, some discrepancies are found between implied stellar masses and the spectroscopic binary mass function or the measured angular separation. These are naturally explained if there is a third star in the system. Multiplicity is also required to explain some comparisons of "cool plus hot binary" IUE and optical spectral energy distribution analysis with measured flux ratios, especially Tycho's two-color photometry of separate components. Out of a sample of 136 cool-plus-hot binary star systems under study, measurements are now indicating several systems considered double (HD 5373, 23089, 26673, 29094, 49126, 71129, 149379, 179002, 187299), and probably a few others (including HD 136415), to have at least three stellar components. Several other cases of suspected triple systems are confirmed. For comparison, there are eight known triples included in the project. In all, about 25% of the systems contain three or more components within a few arcseconds. Estimated separations are provided, which may be of use when not known from interferometry. In general, the triple systems have one post-main-sequence component and two upper main-sequence components, usually revolving around each other. One new triple system, HD 149379, has as its middle component an F giant in the brief first crossing of the Hertzsprung gap.
- ID:
- ivo://CDS.VizieR/VI/107
- Title:
- Tubingen Ultraviolet Echelle Spectrometer
- Short Name:
- VI/107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Tubingen Echelle Spectrograph (TUES), designed and managed at the University of Tubingen, flew on the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrograph (ORFEUS)-SPAS II space shuttle mission in 1996, returning spectra in the 900 Angstrom to 1400 Angstrom wavelength range. The instrument was designed to achieve a spectral resolution of 10000 when used with an entrance aperture of 10" diameter. During the 17.7 day flight, TUES returned 239 spectra of 62 targets.
- ID:
- ivo://CDS.VizieR/J/A+A/632/A46
- Title:
- TW Hydrae association with X-shooter
- Short Name:
- J/A+A/632/A46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Measurements of the protoplanetary disk frequency in young star clusters of different ages indicate disk lifetimes <10Myr. However, our current knowledge of how mass accretion in young stars evolves over the lifespans of disks is subject to many uncertainties, especially at the lower stellar masses. In this study, we investigate ongoing accretion activity in the TW Hydrae association (TWA), the closest association of pre-main sequence stars with active disks. The age (8-10Myr) and the proximity of the TWA render it an ideal target to probe the final stages of disk accretion down to brown dwarf masses. The study is based on homogeneous spectroscopic data from 300nm to 2500nm, obtained synoptically with X-shooter, which allows simultaneous derivation of individual extinction, stellar parameters, and accretion parameters for each star. The continuum excess emission diagnostics is used to estimate the accretion luminosities and mass accretion rates of our disk-bearing targets, and the shape and intensity of permitted and forbidden emission lines are analyzed to probe the physics of the star-disk interaction environment.
- ID:
- ivo://CDS.VizieR/J/ApJ/841/102
- Title:
- Type 2 AGN host galaxies in Chandra-COSMOS
- Short Name:
- J/ApJ/841/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the star formation properties of a large sample of ~2300 X-ray-selected Type 2 Active Galactic Nuclei (AGNs) host galaxies out to z~3 in the Chandra COSMOS Legacy Survey in order to understand the connection between the star formation and nuclear activity. Making use of the existing multi-wavelength photometric data available in the COSMOS field, we perform a multi-component modeling from far-infrared to near-ultraviolet using a nuclear dust torus model, a stellar population model and a starburst model of the spectral energy distributions (SEDs). Through detailed analyses of SEDs, we derive the stellar masses and the star formation rates (SFRs) of Type 2 AGN host galaxies. The stellar mass of our sample is in the range of 9<logM_stellar_/M_{sun}_<12 with uncertainties of ~0.19dex. We find that Type 2 AGN host galaxies have, on average, similar SFRs compared to the normal star-forming galaxies with similar M_stellar_ and redshift ranges, suggesting no significant evidence for enhancement or quenching of star formation. This could be interpreted in a scenario, where the relative massive galaxies have already experienced substantial growth at higher redshift (z>3), and grow slowly through secular fueling processes hosting moderate-luminosity AGNs.
