- ID:
- ivo://CDS.VizieR/J/A+A/342/773
- Title:
- Hot carbon stars B-V colour excess
- Short Name:
- J/A+A/342/773
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A study of 140 hot carbon and related stars. Table 3 contains our hot carbon stars (HC)-classification (see section 2.2 in the paper) for 119 hot carbon stars and their colour excess E(B-V) as determined by the method described in section 2.3. The analogous data for 21 peculiar stars (RCB variables, AC Her [a RV Tau star], V553 Cen [a class II-Cepheid] etc...) can be found in Table 4: most of them have an oxygen-type classification.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/162/188
- Title:
- Hot degenerates in the MCT survey. III.
- Short Name:
- J/AJ/162/188
- Date:
- 21 Mar 2022 00:13:43
- Publisher:
- CDS
- Description:
- We present optical spectra of 144 white dwarfs detected in the Montreal-Cambridge-Tololo colorimetric survey, including 120 DA, 12 DB, 4 DO, 1 DQ, and 7 DC stars. We also perform a model atmosphere analysis of all objects in our sample using the so-called spectroscopic technique, or the photometric technique in the case of DC white dwarfs. The main objective of this paper is to contribute to the ongoing effort of confirming spectroscopically all white dwarf candidates in the Gaia survey, in particular in the southern hemisphere. All our spectra are made available in the Montreal White Dwarf Database.
- ID:
- ivo://CDS.VizieR/J/ApJ/614/671
- Title:
- Hot, dusty ultraluminous galaxies at z~2
- Short Name:
- J/ApJ/614/671
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report spectroscopic redshifts for 18 {mu}Jy radio galaxies at a mean redshift of z=2.2 that are faint at both submillimeter and optical wavelengths. While the radio fluxes of these galaxies could indicate far-IR luminosities comparable to high-redshift submillimeter-selected galaxies (>~10^12^L{Sun}), none are detected in the submillimeter.
- ID:
- ivo://CDS.VizieR/J/ApJ/532/308
- Title:
- Hot Horizontal Branch Stars in the Core of M32
- Short Name:
- J/ApJ/532/308
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- File table1.dat contains the STIS near-UV photometry for the hot stars in the core of M32. The catalog includes 8021 stars, and gives position in the STIS image, magnitude, error, region of the image, RA (J2000), and Dec (J2000). The photometry was performed in six distinct regions of the image because of changes in the point spread function across the image. Note that the relative astrometry is quite accurate (tenths of a 0.025 arcsec STIS pixel), but the absolute astrometry is subject to a 1-2 arcsec uncertainty (associated with the position of the guide stars). Three stars were marked with a footnote in the published catalog, because they are associated with planetary nebulae in our field; they are at the following positions (x,y): (354.949, 821.325), (717.148, 669.210), and (994.924, 355.956).
- ID:
- ivo://CDS.VizieR/J/A+A/622/A81
- Title:
- 15 hot Jupiter exoplanets light curves
- Short Name:
- J/A+A/622/A81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Transit events of extrasolar planets offer a wealth of information for planetary characterization. However, for many known targets, the uncertainty of their predicted transit windows prohibits an accurate scheduling of follow-up observations. In this work, we refine the ephemerides of 21 hot Jupiter exoplanets with the largest timing uncertainties. We collected 120 professional and amateur transit light curves of the targets of interest, observed with a range of telescopes of 0.3m-2.2m, and analyzed them along with the timing information of the planets discovery papers. In the case of WASP-117b, we measured a timing deviation compared to the known ephemeris of about 3.5h, and for HAT-P-29b and HAT-P-31b the deviation amounted to about 2h and more. For all targets, the new ephemeris predicts transit timings with uncertainties of less than 6-min in the year 2018 and less than 13-min until 2025. Thus, our results allow for an accurate scheduling of follow-up observations in the next decade.
- ID:
- ivo://CDS.VizieR/J/A+A/647/A180
- Title:
- hot massive Jupiter NGTS-13b photometry
- Short Name:
- J/A+A/647/A180
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of the massive hot Jupiter NGTS-13b by the Next Generation Transit Survey (NGTS). The V=12.7 host star is likely in the subgiant evolutionary phase with logg_*_=4.04+/-0.05, Teff=5819+/-73K, M_*_=1.30^+0.11^_-0.18_M_{sun}_, and R_*_=1.79+/-0.06R_{sun}_. NGTS detected a transiting planet with a period of P=4.12 days around the star, which was later validated with the Transiting Exoplanet Survey Satellite (TESS; TIC 454069765). We confirm the planet using radial velocities from the CORALIE spectrograph. Using NGTS and TESS full-frame image photometry combined with CORALIE radial velocities we determine NGTS-13b to have a radius of R_P_=1.142+/-0.046R_Jup_, mass of M_P_=4.84+/-0.44M_Jup_ and eccentricity e=0.086+/-0.034. Some previous studies suggest that ~4M_Jup_ may be a border between two separate formation scenarios (e.g., core accretion and disk instability) and that massive giant planets share similar formation mechanisms as lower-mass brown dwarfs. NGTS-13b is just above 4M_Jup_ making it an important addition to the statistical sample needed to understand the differences between various classes of substellar companions. The high metallicity, [Fe/H]=0.25+/-0.17, of NGTS-13 does not support previous suggestions that massive giants are found preferentially around lower metallicity host stars, but NGTS-13b does support findings that more massive and evolved hosts may have a higher occurrence of close-in massive planets than lower-mass unevolved stars.
- ID:
- ivo://CDS.VizieR/J/AJ/131/866
- Title:
- Hot populations in M87 globular clusters
- Short Name:
- J/AJ/131/866
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To explore the production of UV-bright stars in old, metal-rich populations like those in elliptical galaxies, we have obtained Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph far- and near-UV photometry of globular clusters (GCs) in four fields in the giant elliptical (gE) galaxy M87. To a limit of m_FUV_~25 we detect a total of 66 GCs in common with the deep HST optical-band study of Kundu et al. (1999, Cat. <J/ApJ/513/733>).
- ID:
- ivo://CDS.VizieR/J/MNRAS/425/355
- Title:
- Hot stars in LMC UKST H{alpha} survey
- Short Name:
- J/MNRAS/425/355
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new, accurate positions, spectral classifications, radial and rotational velocities, H{alpha} fluxes, equivalent widths and B, V, I, R magnitudes for 579 hot emission-line stars (classes B0-F9) in the Large Magellanic Cloud (LMC) which include 469 new discoveries. Candidate emission-line stars were discovered using a deep, high-resolution H{alpha} map of the central 25 degree^2^ of the LMC obtained by median stacking a dozen 2h H{alpha} exposures taken with the UK Schmidt Telescope (UKST). Spectroscopic follow-up observations on the Anglo-Australian Telescope, the UKST, the Very Large Telescope, the South African Astronomical Observatory 1.9m and the 2.3-m telescope at Siding Spring Observatory have established the identity of these faint sources down to magnitude R_equiv_~23 for H{alpha} (4.5x10^-17^ergs/cm^2^/s/{AA}).
- ID:
- ivo://CDS.VizieR/I/339
- Title:
- Hot Stuff for One Year (HSOY)
- Short Name:
- I/339
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recently, the first installment of data from ESA's Gaia astrometric satellite mission (Gaia DR1) was released, containing positions of more than 1 billion stars with unprecedented precision, as well as proper motions and parallaxes, however only for a subset of 2 million objects. The second release will include those quantities for most objects. In order to provide a dataset that bridges the time gap between the Gaia DR1 and Gaia DR2 releases and partly remedies the lack of proper motions in the former, HSOY ("Hot Stuff for One Year") was created as a hybrid catalog between Gaia and ground-based astrometry, featuring proper motions (but no parallaxes) for a large fraction of the DR1 objects. While not attempting to compete with future Gaia releases in terms of data quality or number of objects, the aim of HSOY is to provide improved proper motions partly based on Gaia data, allowing studies to be carried out just now or as pilot studies for later projects requiring higher-precision data. The HSOY catalog was compiled using the positions taken from Gaia DR1 combined with the input data from the PPMXL catalog, employing the same weighted least-squares technique that was used to assemble the PPMXL catalog itself. This effect resulted in a four-parameter astrometric catalog containing 583 million stars, with Gaia DR1 quality positions and proper motions with precisions from far less than 1 mas/yr to 5 mas/yr, depending on object brightness and location on the sky.
- ID:
- ivo://CDS.VizieR/J/A+A/576/A44
- Title:
- Hot subdwarf binaries from MUCHFUSS
- Short Name:
- J/A+A/576/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims at finding hot subdwarf stars with massive compact companions like massive white dwarfs (M>1.0M_{sun}_), neutron stars, or stellar-mass black holes. The existence of such systems is predicted by binary evolution theory, and recent discoveries indicate that they exist in our Galaxy. We present orbital and atmospheric parameters and put constraints on the nature of the companions of 12 close hot subdwarf B star (sdB) binaries found in the course of the MUCHFUSS project. The systems show periods between 0.14 and 7.4days. In nine cases the nature of the companions cannot be constrained unambiguously whereas three systems most likely have white dwarf companions. We find that the companion to SDSSJ083006.17+475150.3 is likely to be a rare example of a low-mass helium-core white dwarf. SDSSJ095101.28+034757.0 shows an excess in the infrared that probably originates from a third companion in a wide orbit, which makes this system the second candidate hierarchical triple system containing an sdB star. SDSSJ113241.58-063652.8 is the first helium deficient sdO star with a confirmed close companion. This study brings to 142 the number of sdB binaries with orbital periods of less than 30 days and with measured mass functions. We present an analysis of the minimum companion mass distribution and show that it is bimodal. One peak around 0.1M_{sun}_ corresponds to the low-mass main sequence (dM) and substellar companions. The other peak around 0.4M_{sun}_ corresponds to the white dwarf companions. The derived masses for the white dwarf companions are significantly lower than the average mass for single carbon-oxygen white dwarfs. In a T_eff_-logg diagram of sdB+dM companions, we find signs that the sdB components are more massive than the rest of the sample. The full sample was compared to the known population of extremely low-mass white dwarf binaries as well as short-period white dwarfs with main sequence companions. Both samples show a significantly different companion mass distribution indicating either different selection effects or different evolutionary paths. We identified 16 systems where the dM companion will fill its Roche Lobe within a Hubble time and will evolve into a cataclysmic variable; two of them will have a brown dwarf as donor star. Twelve systems with confirmed white dwarf companions will merge within a Hubble time, two of them having a mass ratio to evolve into a stable AMCVn-type binary and another two which are potential supernova Ia progenitor systems. The remaining eight systems will most likely merge and form RCrB stars or massive C/O white dwarfs depending on the structure of the white dwarf companion.
