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- ID:
- ivo://CDS.VizieR/J/A+A/607/A96
- Title:
- HD 166734 ESPRESSO spectra
- Short Name:
- J/A+A/607/A96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HD 166734 is an eccentric eclipsing binary system composed of two supergiant O-type stars, orbiting with a 34.5-day period. In this rare configuration for such stars, the two objects mainly evolve independently, following single-star evolution so far. This system provides a chance to study the individual parameters of two supergiant massive stars and to derive their real masses. An intensive monitoring was dedicated to HD 166734. We analyzed mid- and high-resolution optical spectra to constrain the orbital parameters of this system. We also studied its light curve for the first time, obtained in the VRI filters. Finally, we disentangled the spectra of the two stars and modeled them with the CMFGEN atmosphere code in order to determine the individual physical parameters. HD 166734 is a O7.5If+O9I(f) binary. We confirm its orbital period but we revise the other orbital parameters. In comparison to what we found in the literature, the system is more eccentric and, now, the hottest and the most luminous component is also the most massive one. The light curve exhibits only one eclipse and its analysis indicates an inclination of 63.0+/-2.7{deg}. The photometric analysis provides us with a good estimation of the luminosities of the stars, and therefore their exact positions in the Hertzsprung-Russell diagram. The evolutionary and the spectroscopic masses show good agreement with the dynamical masses of 39.5M_{sun}_ for the primary and 33.5M_{sun}_ for the secondary, within the uncertainties. The two components are both enriched in helium and in nitrogen and depleted in carbon. In addition, the primary also shows a depletion in oxygen. Their surface abundances are however not different from those derived from single supergiant stars, yielding, for both components, an evolution similar to that
- ID:
- ivo://CDS.VizieR/J/ApJ/551/111
- Title:
- HDF early-type and spiral galaxies
- Short Name:
- J/ApJ/551/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the internal optical colors of a complete sample of I_814_<24mag early-type and spiral galaxies from the northern and southern Hubble Deep Fields (HDF). The subset of galaxies in the HDF-North are also investigated in the near-infrared using NICMOS photometry. We compare the central (inner 5% radius) colors of those spirals with clearly visible bulges with the integrated colors of ellipticals in our sample.
- ID:
- ivo://CDS.VizieR/J/A+A/588/A10
- Title:
- HD 149404 FEROS, Coralie and IUE spectra
- Short Name:
- J/A+A/588/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Mass and momentum exchanges in close massive binaries play an important role in their evolution, and produce several observational signatures such as asynchronous rotation and altered chemical compositions, that remain after the stars detach again. We investigated these effects for the detached massive O-star binary HD 149404 (O7.5 If + ON9.7 I, P=9.81-days), which is thought to have experienced a past episode of case A Roche-lobe overflow (RLOF). Using phase-resolved spectroscopy, we performed the disentangling of the optical spectra of the two stars. The reconstructed primary and secondary spectra were then analysed with the CMFGEN model atmosphere code to determine stellar parameters, such as the effective temperatures and surface gravities, and to constrain the chemical composition of the components. We complemented the optical study with the study of IUE spectra, which we compare to the synthetic binary spectra. The properties of the stars were compared to evolutionary models.
- ID:
- ivo://CDS.VizieR/J/ApJ/481/673
- Title:
- HDF flanking fields and related data
- Short Name:
- J/ApJ/481/673
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- File flanking.dat contains Unpublished Catalogue of Galaxies identified by the DEEP Team in the Flanking Fields. This is the source catalogue that Vogt et al. (1997ApJ...479L.121V), Phillips et al. (1997ApJ...489..543P), Guzman et al. (1997ApJ...489..559G), and Mendez & Guzman (1998A&A...333..106M) used to select objects. The photometry in this catalogue was carried out using circular apertures of 3 arcsec diameter, as described by Phillips et al. (1997ApJ...489..543P). These will present small differences (~0.12mag, rms) relative to published values for the sample of 51 compact galaxies that were analysed by Phillips et al. (1997ApJ...489..543P) and Guzman et al. (1997ApJ...489..559G). This is because for the papers, the I(814) magnitudes were recalculated using elliptical apertures to 8 arcsec. The differences should only be significant in the case of galaxies with larger apparent sizes or with elongated shapes.
- ID:
- ivo://CDS.VizieR/J/ApJ/538/29
- Title:
- HDF-N Caltech faint galaxy redshift survey. X.
- Short Name:
- J/ApJ/538/29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A redshift survey has been carried out in the region of the Hubble Deep Field North using the Low Resolution Imaging Spectrograph (LRIS) at the Keck Observatory. The resulting redshift catalog, which contains 671 entries, is a compendium of our own data together with published LRIS/Keck data.
- ID:
- ivo://CDS.VizieR/J/AJ/121/2895
- Title:
- HDF-N Caltech faint galaxy redshift survey. XIII.
- Short Name:
- J/AJ/121/2895
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We introduce a new empirical function for modeling the spectral energy distributions (SEDs) of galaxies. We apply it to a sample of 590 galaxies in the region of the Hubble Deep Field (HDF) with z<1.5 using multicolor photometry with wide wavelength coverage combined with spectroscopic redshifts from our 93% complete R-selected redshift survey there.
- ID:
- ivo://CDS.VizieR/J/AJ/122/598
- Title:
- HDF-North serendipitously galaxies
- Short Name:
- J/AJ/122/598
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 74 galaxies detected serendipitously during a campaign of spectroscopic observations of the Hubble Deep Field North (HDF) and its environs. Among the identified objects are five candidate Ly{alpha} emitters at z>~5, a galaxy cluster at z=0.85, and a Chandra source with a heretofore undetermined redshift of z=2.011. We report redshifts for 25 galaxies in the central HDF, 13 of which had no prior published spectroscopic redshift. Of the remaining 49 galaxies, 30 are located in the single-orbit HDF flanking fields. We discuss the redshift distribution of the serendipitous sample, which contains galaxies in the range 0.10<z<5.77 with a median redshift of z=0.85, and we present strong evidence for redshift clustering. By comparing our spectroscopic redshifts with optical/IR photometric studies of the HDF, we find that photometric redshifts are in most cases capable of producing reasonable predictions of galaxy redshifts. Finally, we estimate the line-of-sight velocity dispersion and the corresponding mass and expected X-ray luminosity of the galaxy cluster, we present strong arguments for interpreting the Chandra source as an obscured active galactic nucleus, and we discuss in detail the spectrum of one of the candidate z>~5 Ly{alpha} emitters.
- ID:
- ivo://CDS.VizieR/J/MNRAS/358/149
- Title:
- HDFN SCUBA Super-map. III
- Short Name:
- J/MNRAS/358/149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new submillimetre (submm) super-map in the Hubble Deep Field North (HDF-N) region (Great Observatories Origins Deep Survey North, GOODS-N, field), containing 40 statistically robust sources at 850um. This map contains additional data, and several new sources, including one of the brightest blank-sky extragalactic submm sources ever detected. We have used the Advanced Camera for Surveys (ACS) Hubble Space Telescope (HST) images and ground-based near-infrared (IR) observations from the Great Observatories Origins Deep Survey (GOODS), along with deep radio observations, to develop a systematic approach for counterpart identification. With the depth achieved by this survey, optical counterparts have been found for all the radio-detected (RD) submm sources.
- ID:
- ivo://CDS.VizieR/J/A+A/364/517
- Title:
- HDF-N spiral and irregular galaxies
- Short Name:
- J/A+A/364/517
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze a morphologically-selected complete sample of 52 late-type (spiral and irregular) galaxies in the Hubble Deep Field North with total K-magnitudes brighter than K=20.47 and typical redshifts z~0.5 to 1.4. This sample exploits in particular the ultimate imaging quality achieved by HST in this field, allowing us to clearly disentangle the early- from late-type galaxy morphologies, based on accurate profiles of the surface brightness distributions.