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- ID:
- ivo://CDS.VizieR/II/168
- Title:
- Homogeneous Means in the UBV System
- Short Name:
- II/168
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The present catalog supersedes an earlier edition of Nicolet (1978). It is a collection of weighted mean photoelectric values (V, B-V, U-B) for stars measured in the UBV system. The mean values were computed by combining all individual measurements compiled in the catalog of Mermilliod (1987), except those that were clearly found to be erroneous for some reason or another. Some newer observations compiled since 1987 are also included in the means. The procedure for computing the homogeneous means involved the calculation of normal averages weighted by the number of observations in each list (unity when not published). New weights are assigned based on the deviation of each value from the previous mean, then a new weighted mean is computed. This technique is not as rigorous as that used by Nicolet (comparison of each list with the standard system master list), but the latter cannot often be realized effectively in practice, since many lists do not contain enough stars in common with a standard list. Also, there are now so many references (more than 1500) that it is not feasible to analyze each publication with respect to a standard list. This edition of the catalog contains 92964 stars measured since the introduction of the UBV system in 1953. The data included are star identification in the Geneva coded numbering system, double and variable codes, UBV data and their standard deviations, and number of observations. A second file contains the definition of the coded numbering system. The catalog was prepared at the Institut d'Astronomie de l'Universite de Lausanne in Geneva.
- ID:
- ivo://CDS.VizieR/II/80
- Title:
- Homogeneous Photometry Bright Stars on DDO System
- Short Name:
- II/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue of homogeneous photometry of bright stars on the DDO (System McClure and Forrester 1981) is a compilation of DDO photometry of 2196 bright G and K stars prepared from observations made at Kitt Peak National and Cerro Tololo Inter-American Observatories over the last several years using filter sets well matched to the standard system. The catalogue includes a large number of DDO stars whose data have been taken directly from the standard-star paper of McClure (1976AJ.....81..182M), plus a representative sample of stars selected from the Catalogue of Bright Stars (Hoffleit 1964, see Cat. V/50) and the Catalogue of High-Velocity Stars (Eggen 1964, see Cat. V/11) to have good velocities, spectral types and freedom from companion contamination. The catalogue contains HD Catalogue numbers, DM identifications; and the standard photometric indices of the DDO system. The number of observations from which each index was determined is also given, along with standard errors. The DDO 6-filter has the following peak wavelengths and widths: ------------------------ Filter Peak Width [nm] [nm] ------------------------ 35 346.0 38.3 38 381.5 33.0 41 416.6 8.3 42 425.7 7.3 45 451.7 7.6 48 488.6 18.6 ------------------------
- ID:
- ivo://CDS.VizieR/J/A+A/623/A127
- Title:
- Homogeneous sample of 34000 M7-M9.5 dwarfs
- Short Name:
- J/A+A/623/A127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The space density of late M dwarfs, sub-types M7 to M9.5, is not well determined. We have applied the photo-type method of Skrzypek et al. to iz photometry from SDSS and YJHK photometry from UKIDSS, over an effective area of 3070deg^2^, to produce a new, bright J(Vega)<17.5, homogeneous sample of 33665 M7 to M9.5 dwarfs. The typical S/N of each source summed over the 6 bands is >100. Classifications are provided to the nearest half spectral sub-type. Through comparison with the classifications in the BUD spectroscopic sample of Schmidt et al. (2010, Cat. J/AJ/139/1808), the typing is shown to be accurately calibrated to the BUD classifications, with a precision better than 0.5 sub-types rms, i.e. is as precise as good spectroscopic classification. Sources with large chisq>20 include several catalogued late-type subdwarfs. The new sample of late M dwarfs is highly complete, but there is a bias in the classification of rare peculiar blue or red objects. For example L subdwarfs are misclassified towards earlier types by approximately two spectral sub-types. We estimate that this bias affects only ~1% of sources. Therefore the sample is well suited for measuring the luminosity function, as well as investigating the softening towards the Galactic plane of the exponential variation of density with height.
- ID:
- ivo://CDS.VizieR/J/PASP/124/693
- Title:
- HO Psc UBV(RI)c light curves
- Short Name:
- J/PASP/124/693
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectrum and a photometric analysis of the newly discovered, high-amplitude, solar-type, eclipsing binary HO Piscium. A spectroscopic identification, a period study, q-search, and a simultaneous UBVRcIc light-curve solution are presented. The spectra and our photometric solution indicate that HO Psc is a W-type W UMa shallow-contact (fill-out ~8%) binary system. The primary component has a G6V spectral type with an apparently precontact spectral type of M2V for the secondary component. The small fill-out indicates that the system has not yet achieved thermal contact and thus has recently come into physical contact. This may mean that this solar-type binary system has not attained its ~0.4 mass ratio via a long period of magnetic braking, as would normally be assumed.
- ID:
- ivo://CDS.VizieR/J/ApJ/685/235
- Title:
- Host and companion galaxies in the SDSS
- Short Name:
- J/ApJ/685/235
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measure the number of companions per galaxy (N_c_) as a function of r-band absolute magnitude for both the Sloan Digital Sky Survey (DR5) and the Croton and coworkers semianalytic catalog, 2006MNRAS.365...11C, applied to the Millennium Run simulation (Springel et al., 2005Natur.435..629S). For close pairs with projected separations of 5-20kpc/h, velocity differences less than 500km/s, and luminosity ratios between 1:2 and 2:1, we find good agreement between the observations and simulations, with N_c_ consistently close to 0.02 over the range -22<M_r_<-18. For larger pair separations, N_c_(M_r_) instead becomes increasingly steep toward the faint end, implying that luminosity-dependent clustering plays an important role on small scales. Using the simulations to assess and correct for projection effects, we infer that the real-space N_c_(M_r_) for close pairs peaks at about M^*^ and declines by at least a factor of 2 as M_r_ becomes fainter. Conversely, by measuring the number density of close companions, we estimate that at least 90% of all major mergers occur between galaxies which are fainter than L^*^. Finally, measurements of the luminosity density of close companions indicate that L^*^ galaxies likely dominate in terms of the overall importance of major mergers in the evolution of galaxy populations at low redshift.
- ID:
- ivo://CDS.VizieR/J/ApJ/722/566
- Title:
- Host galaxies of SNe Ia in SDSS-II SN survey
- Short Name:
- J/ApJ/722/566
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the host galaxy dependences of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe Ia favor passive host galaxies, while brighter, slowly declining Ia's favor star-forming galaxies. We also find evidence (at between 2{sigma} and 3{sigma}) that SNe Ia are ~0.1+/-0.04mag brighter in passive host galaxies than in star-forming hosts, after the SN Ia light curves have been standardized using the light-curve shape and color variations. This difference in brightness is present in both the SALT2 and MCLS2k2 light-curve fitting methodologies. We see evidence for differences in the SN Ia color relationship between passive and star-forming host galaxies, e.g., for the MLCS2k2 technique, we see that SNe Ia in passive hosts favor a dust law of R_V_=1.0+/-0.2, while SNe Ia in star-forming hosts require R_V_=1.8^+0.2^_-0.4_. The significance of these trends depends on the range of SN colors considered. We demonstrate that these effects can be parameterized using the stellar mass of the host galaxy (with a confidence of >4{sigma}) and including this extra parameter provides a better statistical fit to our data. Our results suggest that future cosmological analyses of SN Ia samples should include host galaxy information.
- ID:
- ivo://CDS.VizieR/J/ApJ/830/13
- Title:
- Host-galaxy NUV-NIR data of 32 superluminous SNe
- Short Name:
- J/ApJ/830/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present ultraviolet through near-infrared photometry and spectroscopy of the host galaxies of all superluminous supernovae (SLSNe) discovered by the Palomar Transient Factory prior to 2013 and derive measurements of their luminosities, star formation rates, stellar masses, and gas-phase metallicities. We find that Type I (hydrogen-poor) SLSNe (SLSNe I) are found almost exclusively in low-mass (M_*_<2x10^9^M_{sun}_) and metal-poor (12+log_10_[O/H]<8.4) galaxies. We compare the mass and metallicity distributions of our sample to nearby galaxy catalogs in detail and conclude that the rate of SLSNe I as a fraction of all SNe is heavily suppressed in galaxies with metallicities >~0.5Z_{sun}_. Extremely low metallicities are not required and indeed provide no further increase in the relative SLSN rate. Several SLSN I hosts are undergoing vigorous starbursts, but this may simply be a side effect of metallicity dependence: dwarf galaxies tend to have bursty star formation histories. Type II (hydrogen-rich) SLSNe (SLSNe II) are found over the entire range of galaxy masses and metallicities, and their integrated properties do not suggest a strong preference for (or against) low-mass/low-metallicity galaxies. Two hosts exhibit unusual properties: PTF 10uhf is an SLSN I in a massive, luminous infrared galaxy at redshift z=0.29, while PTF 10tpz is an SLSN II located in the nucleus of an early-type host at z=0.04.
- 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/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.
