- ID:
- ivo://CDS.VizieR/J/MNRAS/463/2125
- Title:
- White dwarf binary pathways survey
- Short Name:
- J/MNRAS/463/2125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The number of spatially unresolved white dwarf plus main-sequence star binaries has increased rapidly in the last decade, jumping from only ~30 in 2003 to over 3000. However, in the majority of known systems the companion to the white dwarf is a low-mass M dwarf, since these are relatively easy to identify from optical colours and spectra. White dwarfs with more massive FGK type companions have remained elusive due to the large difference in optical brightness between the two stars. In this paper, we identify 934 main-sequence FGK stars from the Radial Velocity Experiment survey in the Southern hemisphere and the Large Sky Area Multi-Object Fiber Spectroscopic Telescope survey in the Northern hemisphere, that show excess flux at ultraviolet wavelengths which we interpret as the likely presence of a white dwarf companion. We obtained Hubble Space Telescope ultraviolet spectra for nine systems which confirmed that the excess is indeed caused, in all cases, by a hot compact companion, eight being white dwarfs and one a hot subdwarf or pre-helium white dwarf, demonstrating that this sample is very clean. We also address the potential of this sample to test binary evolution models and Type Ia supernovae formation channels.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/401/1429
- Title:
- WiggleZ dark energy survey (DR1)
- Short Name:
- J/MNRAS/401/1429
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The WiggleZ Dark Energy Survey is a survey of 240000 emission-line galaxies in the distant Universe, measured with the AAOmega spectrograph on the 3.9-m Anglo-Australian Telescope (AAT). The primary aim of the survey is to precisely measure the scale of baryon acoustic oscillations (BAO) imprinted on the spatial distribution of these galaxies at look-back times of 4-8Gyr. The target galaxies are selected using ultraviolet (UV) photometry from the Galaxy Evolution Explorer satellite, with a flux limit of NUV<22.8mag. We also require that the targets are detected at optical wavelengths, specifically in the range 20.0<r<22.5mag. We use the Lyman break method applied to the UV colours, with additional optical colour limits, to select high-redshift galaxies. The galaxies generally have strong emission lines, permitting reliable redshift measurements in relatively short exposure times on the AAT. The median redshift of the galaxies is z_med_=0.6. The redshift range containing 90 per cent of the galaxies is 0.2<z<1.0. The survey will sample a volume of ~1Gpc^3^ over a projected area on the sky of 1000deg^2^, with an average target density of 350deg^-2^.
- ID:
- ivo://CDS.VizieR/J/MNRAS/474/4151
- Title:
- WiggleZ Dark Energy Survey final DR
- Short Name:
- J/MNRAS/474/4151
- Date:
- 02 Mar 2022 00:09:00
- Publisher:
- CDS
- Description:
- The WiggleZ Dark Energy Survey measured the redshifts of over 200000 ultraviolet (UV)-selected (N_UV_<22.8mag) galaxies on the Anglo-Australian Telescope. The survey detected the baryon acoustic oscillation signal in the large-scale distribution of galaxies over the redshift range 0.2<z<1.0, confirming the acceleration of the expansion of the Universe and measuring the rate of structure growth within it. Here, we present the final data release of the survey: a catalogue of 225415 galaxies and individual files of the galaxy spectra. We analyse the emission-line properties of these UV-luminous Lyman-break galaxies by stacking the spectra in bins of luminosity, redshift, and stellar mass. The most luminous (-25mag<M_FUV_< -22mag) galaxies have very broad H{beta} emission from active nuclei, as well as a broad second component to the [OIII] (495.9nm, 500.7nm) doublet lines that is blueshifted by 100km/s, indicating the presence of gas outflows in these galaxies. The composite spectra allow us to detect and measure the temperature-sensitive [OIII] (436.3nm) line and obtain metallicities using the direct method. The metallicities of intermediate stellar mass (8.8<log(M*/M_{sun}_)<10) WiggleZ galaxies are consistent with normal emission-line galaxies at the same masses. In contrast, the metallicities of high stellar mass (10<log(M*/M_{sun}_)<12) WiggleZ galaxies are significantly lower than for normal emission-line galaxies at the same masses. This is not an effect of evolution as the metallicities do not vary with redshift; it is most likely a property specific to the extremely UV-luminous WiggleZ galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/418/841
- Title:
- XMM-Newton observations of N11 in the LMC
- Short Name:
- J/A+A/418/841
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the XMM-Newton observatory, we have observed the giant H II region N11 of the LMC. The field includes three OB associations LH9, LH9, and LH13. Our XMM observations included parallel observations with the OM camera that provided us with unique UV and optical photometry of more than 6000 sources. In this paper we present the photometrical data for these sources as well as their cross-identifications with several catalogues.
295. XMMOMCDFS catalogue
- ID:
- ivo://CDS.VizieR/J/A+A/574/A49
- Title:
- XMMOMCDFS catalogue
- Short Name:
- J/A+A/574/A49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The XMM-Newton X-ray observatory has performed repeated observations of the CDFS in 33 epochs (2001-2010) through the XMM-CDFS Deep Survey. During the X-ray observations, XMM-OM targeted the central 17x17arcmin^2^ region of the X-ray field of view, providing simultaneous optical/UV coverage of the CDFS. The resulting set of data can be taken into account to build an XMM-OM catalogue of the CDFS, filling the UV spectral coverage between the optical surveys and GALEX observations. We present the UV catalogue of the XMM-CDFS Deep Survey. Its main purpose is to provide complementary UV average photometric measurements of known optical/UV sources in the CDFS, taking advantage of the unique characteristics of the survey. The data reduction is intended also to improve the standard source detection on individual observations, by cataloguing faint sources through the stacking of their exposure images. We reprocessed the XMM-OM data of the survey and we stacked the exposures from consecutive observations using the standard SAS tools to process the data obtained during single observations. Average measurements of detections with SAS good quality flags from individual observations and from stacked images have been joined to compile the catalogue. Sources have been validated through the cross-identification within the EIS and COMBO-17 surveys. Photometric data of 1129 CDFS sources are provided into the catalogue, and optical/UV/X-ray photometric and spectroscopic information from other surveys are also included. The stacking extends the detection limits by ~1 mag in the three UV bands, contributing 30% of the catalogued UV sources. The comparison with the available measurements in similar spectral bands confirms the validity of the XMM-OM calibration. The combined COMBO-17/X-ray classification of the "intermediate" sources (e.g. optically diluted and/or X-ray absorbed AGN) is also discussed.
- ID:
- ivo://CDS.VizieR/J/ApJ/840/41
- Title:
- X-ray/UV Swift monitoring of NGC 4151
- Short Name:
- J/ApJ/840/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Swift monitoring of NGC 4151 with an ~6hr sampling over a total of 69days in early 2016 is used to construct light curves covering five bands in the X-rays (0.3-50keV) and six in the ultraviolet (UV)/optical (1900-5500{AA}). The three hardest X-ray bands (>2.5keV) are all strongly correlated with no measurable interband lag, while the two softer bands show lower variability and weaker correlations. The UV/optical bands are significantly correlated with the X-rays, lagging ~3-4days behind the hard X-rays. The variability within the UV/optical bands is also strongly correlated, with the UV appearing to lead the optical by ~0.5-1days. This combination of >~3day lags between the X-rays and UV and <~1day lags within the UV/optical appears to rule out the "lamp-post" reprocessing model in which a hot, X-ray emitting corona directly illuminates the accretion disk, which then reprocesses the energy in the UV/optical. Instead, these results appear consistent with the Gardner & Done (2017MNRAS.470.3591G) picture in which two separate reprocessings occur: first, emission from the corona illuminates an extreme-UV-emitting toroidal component that shields the disk from the corona; this then heats the extreme-UV component, which illuminates the disk and drives its variability.
- ID:
- ivo://CDS.VizieR/J/AJ/139/1066
- Title:
- X-ray view of NGC 2403 central region
- Short Name:
- J/AJ/139/1066
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Archival Chandra observations are used to study the X-ray emission associated with star formation in the central region of the nearby SAB(s)cd galaxy NGC 2403. The distribution of X-ray emission is compared to the morphology visible at other wavelengths using complementary Spitzer, Galaxy Evolution Explorer, and ground-based H{alpha} imagery.
- ID:
- ivo://CDS.VizieR/J/A+A/572/A89
- Title:
- Young stellar object candidates toward Orion
- Short Name:
- J/A+A/572/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze 359 ultraviolet tiles from the All Sky Imaging Survey of the space mission GALEX covering roughly 400 square degrees toward the Orion star-forming region. There are a total of 1555174 ultraviolet sources that were cross-matched with other catalogs (2MASS, UCAC4, SDSS, DENIS, CMC15, and WISE) to produce a list of 290717 reliable sources with a wide range of photometric information. Using different color selection criteria, we identify 111 young stellar object candidates showing both ultraviolet and infrared excesses, of which 81 are new identifications. We discuss the spatial distribution, the spectral energy distributions, and other physical properties of these stars. Their properties are, in general, compatible with those expected for T Tauri stars. This population of TTS candidates is widely dispersed around the Orion molecular cloud.
- ID:
- ivo://CDS.VizieR/J/ApJ/783/119
- Title:
- z~1 Ly{alpha} emitters. I. 135 candidates from GALEX
- Short Name:
- J/ApJ/783/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We construct a flux-limited sample of 135 candidate z~1 Ly{alpha} emitters (LAEs) from Galaxy Evolution Explorer (GALEX) grism data using a new data cube search method. These LAEs have luminosities comparable to those at high redshifts and lie within a 7Gyr gap present in existing LAE samples. We use archival and newly obtained optical spectra to verify the UV redshifts of these LAEs. We use the combination of the GALEX UV spectra, optical spectra, and X-ray imaging data to estimate the active galactic nucleus (AGN) fraction and its dependence on Ly{alpha} luminosity. We remove the AGNs and compute the luminosity function (LF) from 60 z~1 LAE galaxies. We find that the best-fit LF implies a luminosity density increase by a factor of ~1.5 from z~0.3 to z~1 and ~20 from z~1 to z~2. We find a z~1 volumetric Ly{alpha} escape fraction of 0.7%+/-0.4%.
- ID:
- ivo://CDS.VizieR/J/ApJ/826/114
- Title:
- z~3-6 protoclusters in the CFHTLS deep fields
- Short Name:
- J/ApJ/826/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery of three protoclusters at z~3-4 with spectroscopic confirmation in the Canada-France-Hawaii Telescope Legacy Survey Deep Fields. In these fields, we investigate the large-scale projected sky distribution of z~3-6 Lyman-break galaxies and identify 21 protocluster candidates from regions that are overdense at more than 4{sigma} overdensity significance. Based on cosmological simulations, it is expected that more than 76% of these candidates will evolve into a galaxy cluster of at least a halo mass of 10^14^ M_{sun}_ at z=0. We perform follow-up spectroscopy for eight of the candidates using Subaru/FOCAS, Keck II/DEIMOS, and Gemini-N/GMOS. In total we target 462 dropout candidates and obtain 138 spectroscopic redshifts. We confirm three real protoclusters at z=3-4 with more than five members spectroscopically identified and find one to be an incidental overdense region by mere chance alignment. The other four candidate regions at z~5-6 require more spectroscopic follow-up in order to be conclusive. A z=3.67 protocluster, which has 11 spectroscopically confirmed members, shows a remarkable core-like structure composed of a central small region (<0.5 physical Mpc) and an outskirts region (~1.0 physical Mpc). The Ly{alpha} equivalent widths of members of the protocluster are significantly smaller than those of field galaxies at the same redshift, while there is no difference in the UV luminosity distributions. These results imply that some environmental effects start operating as early as at z~4 along with the growth of the protocluster structure. This study provides an important benchmark for our analysis of protoclusters in the upcoming Subaru/HSC imaging survey and its spectroscopic follow-up with the Subaru/PFS that will detect thousands of protoclusters up to z~6.