- ID:
- ivo://CDS.VizieR/J/A+A/596/A49
- Title:
- Synthetic GALEX photometry for IUE sources
- Short Name:
- J/A+A/596/A49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Galaxy Evolution Explorer (GALEX) has produced the largest photometric catalogue of ultraviolet (UV) sources. As such, it has defined the new standard bands for UV photometry: the near UV band (NUV) and the far UV band (FUV). However, due to brightness limits, the GALEX mission has avoided the Galactic plane which is crucial for astrophysical research and future space missions. The International Ultraviolet Explorer (IUE) satellite obtained 63,755 spectra in the low dispersion mode ({lambda}/{delta}{lambda}~300) during its 18-year lifetime. We have derived the photometry in the GALEX bands for the stellar sources in the IUE Archive to extend the GALEX database with observations including the Galactic plane. Good quality spectra have been selected for the IUE classes of stellar sources. The GALEX FUV and NUV magnitudes have been computed using the GALEX transmission curves, as well as the conversion equations between flux and magnitudes provided by the mission (galexgi.gsfc.nasa.gov). Consistency between GALEX and IUE synthetic photometries has been tested using White Dwarfs (WD) contained in both samples. The non-linear response performance of GALEX inferred from this data agrees with the results from GALEX calibration. The photometric database is made available to the community through the services of the Centre de Donnees Stellaires at Strasbourg (CDS). The catalogue contains FUV magnitudes for 1628 sources, ranging from FUV=1.81 to FUV=18.65mag. In the NUV band, the catalogue includes observations for 999 stars ranging from NUV=3.34 to NUV=17.74mag. UV photometry for 1490 sources not included in the GALEX AIS GR5 catalogue is provided; most of them are hot (O-A spectral type) stars. The sources in the catalogue are distributed over the full sky, including the Galactic plane.
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- ID:
- ivo://CDS.VizieR/J/ApJS/224/36
- Title:
- The AllWISE motion survey (AllWISE2)
- Short Name:
- J/ApJS/224/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the AllWISE Data Release to continue our search for Wide-field Infrared Survey Explorer (WISE)-detected motions. In this paper, we publish another 27846 motion objects, bringing the total number to 48000 when objects found during our original AllWISE motion survey are included. We use this list, along with the lists of confirmed WISE-based motion objects from the recent papers by Luhman (2014, J/ApJ/781/4) and by Schneider et al. (2016, J/ApJ/817/112), and candidate motion objects from the recent paper by Gagne et al. (2014, J/ApJ/783/121), to search for widely separated, common-proper-motion systems. We identify 1039 such candidate systems. All 48000 objects are further analyzed using color-color and color-mag plots to provide possible characterizations prior to spectroscopic follow-up. We present spectra of 172 of these, supplemented with new spectra of 23 comparison objects from the literature, and provide classifications and physical interpretations of interesting sources. Highlights include: (1) the identification of three G/K dwarfs that can be used as standard candles to study clumpiness and grain size in nearby molecular clouds because these objects are currently moving behind the clouds, (2) the confirmation/discovery of several M, L, and T dwarfs and one white dwarf whose spectrophotometric distance estimates place them 5-20pc from the Sun, (3) the suggestion that the Na I "D" line be used as a diagnostic tool for interpreting and classifying metal-poor late-M and L dwarfs, (4) the recognition of a triple system including a carbon dwarf and late-M subdwarf, for which model fits of the late-M subdwarf (giving [Fe/H]~-1.0) provide a measured metallicity for the carbon star, and (5) a possible 24pc distant K5 dwarf + peculiar red L5 system with an apparent physical separation of 0.1pc.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/24
- Title:
- The COSMOS2015 catalog
- Short Name:
- J/ApJS/224/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the COSMOS2015 catalog, which contains precise photometric redshifts and stellar masses for more than half a million objects over the 2deg^2^ COSMOS field. Including new YJHKs images from the UltraVISTA-DR2 survey, Y-band images from Subaru/Hyper-Suprime-Cam, and infrared data from the Spitzer Large Area Survey with the Hyper-Suprime-Cam (SPLASH) Spitzer legacy program, this near-infrared-selected catalog is highly optimized for the study of galaxy evolution and environments in the early universe. To maximize catalog completeness for bluer objects and at higher redshifts, objects have been detected on a {chi}^2^ sum of the YJHKs and z^++^ images. The catalog contains ~6x10^5^ objects in the 1.5deg^2^ UltraVISTA-DR2 region and ~1.5x10^5^ objects are detected in the "ultra-deep stripes" (0.62deg^2^) at Ks<=24.7 (3{sigma}, 3", AB (AB) magnitude). Through a comparison with the zCOSMOS-bright spectroscopic redshifts, we measure a photometric redshift precision of {sigma}_{Delta}z/(1+zs)_=0.007 and a catastrophic failure fraction of {eta}=0.5%. At 3<z<6 , using the unique database of spectroscopic redshifts in COSMOS, we find {sigma}_{Delta}z/(1+zs)_=0.021 and {eta}=13.2% . The deepest regions reach a 90% completeness limit of 10^10^M_{sun}_ to z=4. Detailed comparisons of the color distributions, number counts, and clustering show excellent agreement with the literature in the same mass ranges. COSMOS2015 represents a unique, publicly available, valuable resource with which to investigate the evolution of galaxies within their environment back to the earliest stages of the history of the universe.
- ID:
- ivo://CDS.VizieR/J/ApJ/863/144
- Title:
- The ELQS in SDSS footprint. II. North Gal. Cap
- Short Name:
- J/ApJ/863/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the North Galactic Cap sample of the Extremely Luminous Quasar Survey (ELQS-N), which targets quasars with M_1450_{<}-27 at 2.8<=z<5 in an area of ~7600deg^2^ of the Sloan Digital Sky Survey (SDSS) footprint with 90{deg}<RA<270{deg}. Based on a near-infrared/infrared JKW2 color cut, the ELQS selection efficiently uses random forest methods to classify quasars and to estimate photometric redshifts; this scheme overcomes some of the difficulties of pure optical quasar selection at z~3. As a result, we retain a completeness of >70% over z~3.0-5.0 at m_i_<~17.5, limited toward fainter magnitudes by the depth of the Two Micron All Sky Survey. The presented quasar catalog consists of a total of 270 objects, of which 39 are newly identified in this work with spectroscopy obtained at the Vatican Advanced Technology Telescope and the MMT 6.5m telescope. In addition to the high completeness, which allowed us to discover new quasars in the already well-surveyed SDSS North Galactic Cap, the efficiency of our selection is relatively high at ~79%. Using 120 objects of this quasar sample we are able to extend the previously measured optical quasar luminosity function (QLF) by one magnitude toward the bright end at 2.8<=z<=4.5. A first analysis of the QLF suggests a relatively steep bright-end slope of {beta}~-4 for this sample. This result contrasts with previous results in the same redshift range, which find a much flatter slope around {beta}~-2.5, but agrees with recent measurements of the bright-end slope at lower and higher redshifts. Our results constrain the bright-end slope at z=2.8-4.5 to {beta}{<}-2.94 with a 99% confidence.
- ID:
- ivo://CDS.VizieR/J/ApJS/243/5
- Title:
- The ELQS in the PS1 footprint (PS-ELQS)
- Short Name:
- J/ApJS/243/5
- Date:
- 08 Mar 2022 13:10:17
- Publisher:
- CDS
- Description:
- We present the results of the Extremely Luminous Quasar Survey in the 3{pi} survey of the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS; PS1). This effort applies the successful quasar selection strategy of the Extremely Luminous Survey in the Sloan Digital Sky Survey footprint (~12000deg^2^) to a much larger area (~21486deg^2^). This spectroscopic survey targets the most luminous quasars (M_1450_<=-26.5; m_i_<=18.5) at intermediate redshifts (z>=2.8). Candidates are selected based on a near-infrared JKW2 color cut using WISE AllWISE and 2MASS photometry to mainly reject stellar contaminants. Photometric redshifts (z_reg_) and star-quasar classifications for each candidate are calculated from near-infrared and optical photometry using the supervised machine learning technique random forests. We select 806 quasar candidates at z_reg_>=2.8 from a parent sample of 74318 sources. After exclusion of known sources and rejection of candidates with unreliable photometry, we have taken optical identification spectra for 290 of our 334 good PS-ELQS candidates. We report the discovery of 190 new z>=2.8 quasars and an additional 28 quasars at lower redshifts. A total of 44 good PS-ELQS candidates remain unobserved. Including all known quasars at z>=2.8, our quasar selection method has a selection efficiency of at least 77%. At lower declinations, -30<=DEC<=0, we approximately treble the known population of extremely luminous quasars. We provide the PS-ELQS quasar catalog with a total of 592 luminous quasars (m_i_<=18.5, z>=2.8). This unique sample will not only be able to provide constraints on the volume density and quasar clustering of extremely luminous quasars, but also offers valuable targets for studies of the intergalactic medium.
- 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/ApJS/187/64
- Title:
- The simultaneous optical-to-X-ray SED of AGNs
- Short Name:
- J/ApJS/187/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report Swift observations of a sample of 92 bright soft X-ray selected active galactic nuclei (AGNs). This sample represents the largest number of AGNs observed to study the spectral energy distribution (SED) of AGNs with simultaneous optical/UV and X-ray data. The principal motivation of this study is to understand the SEDs of AGNs in the optical/UV to X-ray regime and to provide bolometric corrections which are important in determining the Eddington ratio L/L_Edd_. In particular, we rigorously explore the dependence of the UV-EUV contribution to the bolometric correction on the assumed EUV spectral shape. We find strong correlations of the spectral slopes {alpha}_X_ and {alpha}_UV_ with L/L_Edd_.
- ID:
- ivo://CDS.VizieR/J/ApJ/796/L18
- Title:
- Type Ia supernova 2011de UVOT photometry
- Short Name:
- J/ApJ/796/L18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present and discuss the ultraviolet (UV)/optical photometric light curves and absolute magnitudes of the Type Ia supernova (SN Ia) 2011de from the Swift Ultraviolet/Optical Telescope. We find it to be the UV brightest SN Ia yet observed - more than a factor of 10 brighter than normal SNe Ia in the mid-ultraviolet. We find that the UV/optical brightness and broad light curve evolution can be modeled with additional flux from the shock of the ejecta hitting a relatively large red giant companion separated by 6x10^13^ cm. However, the post-maximum behavior of other UV-bright SNe Ia can also be modeled in a similar manner, including objects with UV spectroscopy or pre-maximum photometry which is inconsistent with this model. This suggests that similar UV luminosities can be intrinsic or caused by other forms of shock interaction. The high velocities reported for SN 2011de make it distinct from the UV-bright "super-Chandrasekhar" SNe Ia and the NUV-blue group of normal SNe Ia. SN 2011de is an extreme example of the UV variations in SNe Ia.
- ID:
- ivo://CDS.VizieR/J/ApJS/104/287
- Title:
- UIT near-UV bright objects catalog
- Short Name:
- J/ApJS/104/287
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a photometric catalog of 2244 objects detected by the Ultraviolet Imaging Telescope in the near-ultraviolet (NUV; 1650A<lambda<2900A) during the Astro-1 Space Shuttle mission. Sources in the catalog are as faint as m_nuv~18.8, or f_nuv~1.1x10^-16ergs/s/cm^2/A, but the survey is not complete to this level. Optical catalogs were used to cross identify sources and derive NUV-V colors. A majority of the objects (88%) do indeed have proposed optical identifications from catalogs, and most are stars. Our purpose in creating the catalog is to form a database useful for identifying very blue objects and performing Galactic UV stellar population studies.
- ID:
- ivo://CDS.VizieR/J/A+A/598/A1
- Title:
- [U]LIRGs - on the trail of AGN's types
- Short Name:
- J/A+A/598/A1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The aim of this work is to characterize physical properties of Ultra Luminous Infrared Galaxies (ULIRGs) and Luminous Infrared Galaxies (LIRGs) detected in the far-infrared (FIR) 90um band in the AKARI Deep Field-South (ADF-S) survey. In particular, we want to estimate the active galactic nucleus (AGN) contribution to the LIRGs and ULIRGs' infrared emission and which types of AGNs are related to their activity. We examined 69 galaxies at redshift >=0.05 detected at 90um by the AKARI satellite in the AKARI Deep-Field South (ADF-S), with optical counterparts and spectral coverage from the ultraviolet to the FIR. We used two independent spectral energy distribution fitting codes: one fitting the SED from FIR to FUV (CIGALE) (we use the results from CIGALE as a reference) and gray-body + power spectrum fit for the infrared part of the spectra (CMCIRSED) in order to identify a subsample of ULIRGs and LIRGs, and to estimate their properties. A final catalog of 39 LIRGs and ULIRGs is used for our analysis.