- ID:
- ivo://CDS.VizieR/J/ApJ/845/72
- Title:
- The factory & the beehive. III. PTFEB132.707+19.810
- Short Name:
- J/ApJ/845/72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Theoretical models of stars constitute the fundamental bedrock upon which much of astrophysics is built, but large swaths of model parameter space remain uncalibrated by observations. The best calibrators are eclipsing binaries in clusters, allowing measurement of masses, radii, luminosities, and temperatures for stars of known metallicity and age. We present the discovery and detailed characterization of PTFEB132.707+19.810, a P=6.0day eclipsing binary in the Praesepe cluster ({tau}~600-800Myr; [Fe/H]=0.14+/-0.04). The system contains two late-type stars (SpT_P_=M3.5+/-0.2; SpT_S_=M4.3+/-0.7) with precise masses (M_p_=0.3953+/-0.0020M_{sun}_; M_s_=0.2098+/-0.0014M_{sun}_) and radii (R_p_=0.363+/-0.008R_{sun}_; R_s_=0.272+/-0.012R_{sun}_). Neither star meets the predictions of stellar evolutionary models. The primary has the expected radius but is cooler and less luminous, while the secondary has the expected luminosity but is cooler and substantially larger (by 20%). The system is not tidally locked or circularized. Exploiting a fortuitous 4:5 commensurability between Porb and P_rot,prim_, we demonstrate that fitting errors from the unknown spot configuration only change the inferred radii by <~1%-2%. We also analyze subsets of data to test the robustness of radius measurements; the radius sum is more robust to systematic errors and preferable for model comparisons. We also test plausible changes in limb darkening and find corresponding uncertainties of ~1%. Finally, we validate our pipeline using extant data for GU Boo, finding that our independent results match previous radii to within the mutual uncertainties (2%-3%). We therefore suggest that the substantial discrepancies are astrophysical; since they are larger than those for old field stars, they may be tied to the intermediate age of PTFEB132.707+19.810.
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- ID:
- ivo://CDS.VizieR/J/ApJ/863/181
- Title:
- The fifth catalog of LMC Wolf-Rayet stars
- Short Name:
- J/ApJ/863/181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We summarize the results of our 4yr survey searching for Wolf-Rayet (WR) stars in the Large Magellanic Cloud (LMC) and Small Magellanic Cloud. Over the course of this survey we have discovered 15 new WR stars and 12 Of-type stars. In this last year we discovered two rare Of-type stars: an O6.5f?p and an O6nfp, in addition to the two new Of?p stars discovered in our first year and the three Onfp stars discovered in our second and third years. However, even more exciting was our discovery of a new type of WR star, ones we are calling WN3/O3s owing to their spectroscopic signatures. We describe the completeness limits of our survey and demonstrate that we are sensitive to weak-lined WRs several magnitudes fainter than any we have discovered, arguing that there is not a population of fainter WRs waiting to be discovered. We discuss the nature of the WN3/O3s, summarizing the results of our extensive spectroscopy and modeling. We also examine the important claim made by others that the WN3/O3s are isolated compared to other massive stars. We find that if we use a more complete sample of reference massive stars, the WN3/O3s show the same spatial distribution as other early WNs, consistent with a common origin. Finally, we use this opportunity to present the "Fifth Catalog of LMC Wolf-Rayet Stars," which includes revised coordinates and updated spectral types for all 154 known LMC WRs.
- ID:
- ivo://CDS.VizieR/J/AJ/112/407
- Title:
- The FIRST bright QSO survey
- Short Name:
- J/AJ/112/407
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The FIRST radio survey provides a new resource for constructing a large quasar sample. With source positions accurate to better than 1" and a point source sensitivity limit of 1mJy, it reaches 50 times deeper than previous radio catalogs. We report here on the results of the pilot phase for a FIRST Bright Quasar Survey (FBQS). Based on matching the radio catalog from the initial 300{deg}^2^ of FIRST coverage with the optical catalog from the Automated Plate Machine (APM) digitization of Palomar Sky Survey plates, we have defined a sample of 219 quasar candidates brighter than E=17.50. We have obtained optical spectroscopy for 151 of these and classified 25 others from the literature, yielding 69 quasars or Seyfert 1 galaxies, of which 51 are new identifications. The brightest new quasar has an E magnitude of 14.6 and z=0.91; four others are brighter than E=16. The redshifts range from z=0.12 to 3.42. Half of the detected objects are radio quiet with L_21-cm_<10^32.5^ergs/s. We use the results of this pilot survey to establish criteria for the FBQS that will produce a quasar search program which will be 70% efficient and 95% complete to a 21-cm flux density limit of 1.0mJy.
- ID:
- ivo://CDS.VizieR/J/ApJ/698/1095
- Title:
- The FIRST-2MASS red QSO survey. II.
- Short Name:
- J/ApJ/698/1095
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results on a survey to find extremely dust-reddened Type 1 quasars. Combining the FIRST radio survey, the 2MASS Infrared Survey and the Sloan Digital Sky Survey, we have selected a candidate list of 122 potential red quasars. With more than 80% spectroscopically identified objects, well over 50% are classified as dust-reddened Type 1 quasars, whose reddenings (E(B-V)) range from approximately 0.1 to 1.5mag. They lie well off the color selection windows usually used to detect quasars and many fall within the stellar locus, which would have made it impossible to find these objects with traditional color selection techniques. The reddenings found are much more consistent with obscuration happening in the host galaxy rather than stemming from the dust torus. We find an unusually high fraction of broad absorption line (BAL) quasars at high redshift, all but one of them belonging to the low-ionization BAL (LoBAL) class and many also showing absorption in the metastable FeII line (FeLoBAL). The discovery of further examples of dust-reddened LoBAL quasars provides more support for the hypothesis that BAL quasars (at least LoBAL quasars) represent an early stage in the lifetime of the quasar. The fact that we see such a high fraction of BALs could indicate that the quasar is in a young phase in which quasar feedback from the BAL winds is suppressing star formation in the host galaxy.
- ID:
- ivo://CDS.VizieR/J/AJ/158/13
- Title:
- The first 300 stars observed by the GPIES
- Short Name:
- J/AJ/158/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a statistical analysis of the first 300 stars observed by the Gemini Planet Imager Exoplanet Survey. This subsample includes six detected planets and three brown dwarfs; from these detections and our contrast curves we infer the underlying distributions of substellar companions with respect to their mass, semimajor axis, and host stellar mass. We uncover a strong correlation between planet occurrence rate and host star mass, with stars M_*_>1.5 M_{sun}_ more likely to host planets with masses between 2 and 13 M_Jup_ and semimajor axes of 3-100 au at 99.92% confidence. We fit a double power-law model in planet mass (m) and semimajor axis (a) for planet populations around high-mass stars (M_*_>1.5 M_{sun}_) of the form d^2^N/(dm da){prop.to}m^{alpha}^{alpha}^{beta}^, finding {alpha}=-2.4+/-0.8 and {beta}=-2.0+/-0.5, and an integrated occurrence rate of 9_-4_^+5^% between 5-13 M_Jup_ and 10-100 au. A significantly lower occurrence rate is obtained for brown dwarfs around all stars, with 0.8_-0.5_^+0.8^% of stars hosting a brown dwarf companion between 13-80 M_Jup_ and 10-100 au. Brown dwarfs also appear to be distributed differently in mass and semimajor axis compared to giant planets; whereas giant planets follow a bottom-heavy mass distribution and favor smaller semimajor axes, brown dwarfs exhibit just the opposite behaviors. Comparing to studies of short-period giant planets from the radial velocity method, our results are consistent with a peak in occurrence of giant planets between ~1 and 10 au. We discuss how these trends, including the preference of giant planets for high-mass host stars, point to formation of giant planets by core/pebble accretion, and formation of brown dwarfs by gravitational instability.
- ID:
- ivo://CDS.VizieR/J/ApJ/690/163
- Title:
- The first Swift UV-Opt GRB afterglow catalog
- Short Name:
- J/ApJ/690/163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first Swift Ultraviolet/Optical Telescope (UVOT) gamma-ray burst (GRB) afterglow catalog. The catalog contains data from over 64000 independent UVOT image observations of 229 GRBs first detected by Swift, the High Energy Transient Explorer 2 (HETE2), the International Gamma-Ray Astrophysics Laboratory (INTEGRAL), and the Interplanetary Network (IPN). The catalog covers GRBs occurring during the period from 2005 January 17 to 2007 June 16 and includes ~86% of the bursts detected by the Swift Burst Alert Telescope (BAT). The catalog provides detailed burst positional, temporal, and photometric information extracted from each of the UVOT images. Positions for bursts detected at the 3{sigma} level are provided with a nominal accuracy, relative to the USNO-B1 catalog, of ~0.25". Photometry for each burst is given in three UV bands, three optical bands, and a "white" or open filter. Upper limits for magnitudes are reported for sources detected below 3{sigma}. General properties of the burst sample and light curves, including the filter-dependent temporal slopes, are also provided.
- ID:
- ivo://CDS.VizieR/J/ApJ/874/150
- Title:
- The first 3yrs of DES-SN (DES-SN3YR)
- Short Name:
- J/ApJ/874/150
- Date:
- 08 Dec 2021
- Publisher:
- CDS
- Description:
- We present the analysis underpinning the measurement of cosmological parameters from 207 spectroscopically classified SNe Ia from the first 3 years of the Dark Energy Survey Supernova Program (DES-SN), spanning a redshift range of 0.017<z<0.849. We combine the DES-SN sample with an external sample of 122 low-redshift (z<0.1) SNe Ia, resulting in a "DES-SN3YR" sample of 329 SNe Ia. Our cosmological analyses are blinded: after combining our DES-SN3YR distances with constraints from the Cosmic Microwave Background, our uncertainties in the measurement of the dark energy equation-of-state parameter, w, are 0.042 (stat) and 0.059 (stat+syst) at 68% confidence. We provide a detailed systematic uncertainty budget, which has nearly equal contributions from photometric calibration, astrophysical bias corrections, and instrumental bias corrections. We also include several new sources of systematic uncertainty. While our sample is less than one-third the size of the Pantheon sample, our constraints on w are only larger by 1.4x, showing the impact of the DES-SN Ia light-curve quality. We find that the traditional stretch and color standardization parameters of the DES-SNe Ia are in agreement with earlier SN Ia samples such as Pan-STARRS1 and the Supernova Legacy Survey. However, we find smaller intrinsic scatter about the Hubble diagram (0.077mag). Interestingly, we find no evidence for a Hubble residual step (0.007+/-0.018mag) as a function of host-galaxy mass for the DES subset, in 2.4{sigma} tension with previous measurements. We also present novel validation methods of our sample using simulated SNe Ia inserted in DECam images and using large catalog-level simulations to test for biases in our analysis pipelines.
- ID:
- ivo://CDS.VizieR/I/261
- Title:
- The FON Astrographic Catalogue (FONAC)
- Short Name:
- I/261
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The FONAC is a catalogue of positions, proper motions and photometric data for 2,008,383 of Astrographic Catalogue (AC) stars covering the sky between declinations +90 and -2 degrees. The average epoch of positions is 1988.19. The catalogue is based on the measurements of more then 1700 plates which were taken with the wide-angle astrograph of the Main Astronomical Observatory (MAO) in Kiev within the FON (Photographic Survey of the Northern Sky) project. The AC data were used both as the input catalogue for measuring machine PARSEC (Programming Automatic Radial-Scanning Coordinatometer) and as the first epochs for determination of proper motions of stars. The ACT Reference Catalogue was applied for the reductions of positions and B magnitudes of stars, the GSC1.1 was used for determination of (B-V) values, and the USNO R-magnitudes were used for determination of (B-R) values. The estimated precision is 0.2 arcseconds for the positions, 3 mas/yr for the proper motions, and 0.18mag for the photometry.
- ID:
- ivo://CDS.VizieR/J/A+A/639/A136
- Title:
- The Fornax Deep Survey with the VST. IX.
- Short Name:
- J/A+A/639/A136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A possible pathway for understanding the events and the mechanisms involved in galaxy formation and evolution is an in-depth comprehension of the galactic and inter-galactic fossil sub-structures with long dynamical times-scales: stars in the field and in stellar clusters. This paper continues the series of the Fornax Deep Survey (FDS). Following the previous studies dedicated to extended Fornax cluster members, in this paper we present the catalogs of compact stellar systems in the Fornax cluster as well as extended background sources and point-like sources. We derive ugri photometry of ~1.7 million sources over the ~21 square degree area of FDS centered on the bright central galaxy NGC1399. For a wider area, of ~27 square degrees extending in the direction of NGC1316, we provide gri photometry for ~3.1 million sources. To improve the morphological characterization of sources we generate multi-band image stacks by coadding the best seeing gri-band single exposures with a cut at FWHM<=0.9". We use the multi-band stacks as master detection frames, with a FWHM improved by ~15% and a FWHM variability from field to field reduced by a factor of ~2.5 compared to the pass-band with best FWHM, namely the r-band. The identification of compact sources, in particular of globular clusters (GC), is obtained from a combination of photometric (e.g. colors, magnitudes) and morphometric (e.g. concentration index, elongation, effective radius) selection criteria, by also taking as reference the properties of sources with well-defined classification from spectroscopic or high-resolution imaging data. Using the FDS catalogs, we present a preliminary analysis of globular cluster (GC) distributions in the Fornax area. The study confirms and extends further previous results which were limited to a smaller survey area. We observe the inter-galactic population of GCs, a population of mainly blue GCs centered on NGC1399, extends over ~0.9Mpc, with an ellipticity ~0.65 and a small tilt in the direction of NGC1336. Several sub-structures extend over ~0.5Mpc along various directions. Two of these structures do not cross any bright galaxy; one of them appears to be connected to NGC1404, a bright galaxy close to the cluster core and particularly poor of GCs. Using the gri catalogs we analyze the GC distribution over the extended FDS area, and do not find any obvious GC sub-structure bridging the two brightest cluster galaxies, NGC1316 and NGC1399. Although NGC1316 is more than twice brighter of NGC1399 in optical bands, using gri data, we estimate a factor of ~3-4 richer GC population around NGC1399 compared to NGC1316, out to galactocentric distances of ~40' or ~230kpc
- ID:
- ivo://CDS.VizieR/J/ApJS/236/37
- Title:
- The Gaia-WISE extragalactic astrometric catalog
- Short Name:
- J/ApJS/236/37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Gaia mission has detected a large number of active galactic nuclei (AGNs) and galaxies, but these objects must be identified among the thousandfold more numerous stars. Extant astrometric AGN catalogs do not have the uniform sky coverage required to detect and characterize the all-sky, low-multipole proper motion signals produced by the barycenter motion, gravitational waves, and cosmological effects. To remedy this, we present an all-sky sample of 567,721 AGNs in Gaia Data Release 1, selected using WISE two-color criteria. The catalog has fairly uniform sky coverage beyond the Galactic plane, with a mean density of 12.8 AGNs per square degree. The objects have magnitudes ranging from G=8.8 down to Gaia's magnitude limit, G=20.7. The catalog is approximately 50% complete but suffers from low stellar contamination, roughly 0.2%. We predict that the end-of-mission Gaia proper motions for this catalog will enable detection of the secular aberration drift to high significance (23{sigma}) and will place an upper limit on the anisotropy of the Hubble expansion of about 2%.