- ID:
- ivo://CDS.VizieR/J/AJ/155/180
- Title:
- A catalog of cool dwarf targets for the TESS
- Short Name:
- J/AJ/155/180
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of cool dwarf targets (V-J>2.7, T_eff_~<4000 K) and their stellar properties for the upcoming Transiting Exoplanet Survey Satellite (TESS), for the purpose of determining which cool dwarfs should be observed using two minute observations. TESS has the opportunity to search tens of thousands of nearby, cool, late K- and M-type dwarfs for transiting exoplanets, an order of magnitude more than current or previous transiting exoplanet surveys, such as Kepler, K2, and ground-based programs. This necessitates a new approach to choosing cool dwarf targets. Cool dwarfs are chosen by collating parallax and proper motion catalogs from the literature and subjecting them to a variety of selection criteria. We calculate stellar parameters and TESS magnitudes using the best possible relations from the literature while maintaining uniformity of methods for the sake of reproducibility. We estimate the expected planet yield from TESS observations using statistical results from the Kepler mission, and use these results to choose the best targets for two minute observations, optimizing for small planets for which masses can conceivably be measured using follow-up Doppler spectroscopy by current and future Doppler spectrometers. The catalog is available in machine readable format and is incorporated into the TESS Input Catalog and TESS Candidate Target List until a more complete and accurate cool dwarf catalog identified by ESA's Gaia mission can be incorporated.
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- ID:
- ivo://CDS.VizieR/J/ApJS/212/18
- Title:
- An atlas of UV-to-MIR galaxy SEDs
- Short Name:
- J/ApJS/212/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an atlas of 129 spectral energy distributions for nearby galaxies, with wavelength coverage spanning from the ultraviolet to the mid-infrared. Our atlas spans a broad range of galaxy types, including ellipticals, spirals, merging galaxies, blue compact dwarfs, and luminous infrared galaxies. We have combined ground-based optical drift-scan spectrophotometry with infrared spectroscopy from Spitzer and Akari with gaps in spectral coverage being filled using Multi-wavelength Analysis of Galaxy Physical Properties spectral energy distribution models. The spectroscopy and models were normalized, constrained, and verified with matched-aperture photometry measured from Swift, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, Spitzer, and Wide-field Infrared Space Explorer images. The availability of 26 photometric bands allowed us to identify and mitigate systematic errors present in the data. Comparison of our spectral energy distributions with other template libraries and the observed colors of galaxies indicates that we have smaller systematic errors than existing atlases, while spanning a broader range of galaxy types. Relative to the prior literature, our atlas will provide improved K-corrections, photometric redshifts, and star-formation rate calibrations.
- ID:
- ivo://CDS.VizieR/J/A+A/538/A26
- Title:
- BL Lac objects beyond z=1.3
- Short Name:
- J/A+A/538/A26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of the {gamma}-ray sky with Fermi led to significant advances towards understanding blazars, the most extreme class of active galactic nuclei. A large fraction of the population detected by Fermi is formed by BL Lacertae (BL Lac) objects, whose sample has always suffered from a severe redshift incompleteness due to the quasi-featureless optical spectra. Our goal is to provide a significant increase of the number of confirmed high-redshift BL Lac objects contained in the 2 LAC Fermi/LAT catalog.
- ID:
- ivo://CDS.VizieR/J/ApJ/765/12
- Title:
- Carbon stars and DQ white dwarfs from SDSS-DR7+DR8
- Short Name:
- J/ApJ/765/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Among stars showing carbon molecular bands (C stars), the main-sequence dwarfs, likely in post-mass transfer binaries, are numerically dominant in the Galaxy. Via spectroscopic selection from the Sloan Digital Sky Survey, we retrieve 1220 high galactic latitude C stars, ~5 times more than previously known, including a wider variety than past techniques such as color or grism selection have netted, and additionally yielding 167 DQ white dwarfs. Of the C stars with proper motion measurements, we identify 69% clearly as dwarfs (dCs), while ~7% are giants. The dCs likely span absolute magnitudes M_i_ from ~6.5 to 10.5. "G-type" dC stars with weak CN and relatively blue colors are probably the most massive dCs still cool enough to show C_2_bands. We report Balmer emission in 22 dCs, none of which are G-types. We find 8 new DA/dC stars in composite spectrum binaries, quadrupling the total sample of these "smoking guns" for AGB binary mass transfer. Eleven very red C stars with strong red CN bands appear to be "N"-type AGB stars at large Galactocentric distances, one likely a new discovery in the dIrr galaxy Leo A. Two such stars within 30' of each other may trace a previously unidentified dwarf galaxy or tidal stream at ~40 kpc. We explore the multiwavelength properties of the sample and report the first X-ray detection of a dC star, which shows strong Balmer emission. Our own spectroscopic survey additionally provides the dC surface density from a complete sample of dwarfs limited by magnitude, color, and proper motion.
- ID:
- ivo://CDS.VizieR/J/AJ/153/95
- Title:
- Catalog of Suspected Nearby Young Stars
- Short Name:
- J/AJ/153/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new nearby young moving group (NYMG) kinematic membership analysis code, LocAting Constituent mEmbers In Nearby Groups (LACEwING), a new Catalog of Suspected Nearby Young Stars, a new list of bona fide members of moving groups, and a kinematic traceback code. LACEwING is a convergence-style algorithm with carefully vetted membership statistics based on a large numerical simulation of the Solar Neighborhood. Given spatial and kinematic information on stars, LACEwING calculates membership probabilities in 13 NYMGs and three open clusters within 100 pc. In addition to describing the inputs, methods, and products of the code, we provide comparisons of LACEwING to other popular kinematic moving group membership identification codes. As a proof of concept, we use LACEwING to reconsider the membership of 930 stellar systems in the Solar Neighborhood (within 100 pc) that have reported measurable lithium equivalent widths. We quantify the evidence in support of a population of young stars not attached to any NYMGs, which is a possible sign of new as-yet-undiscovered groups or of a field population of young stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/813/100
- Title:
- Deep GALEX NUV survey of the Kepler field. I.
- Short Name:
- J/ApJ/813/100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report observations of a deep near-ultraviolet (NUV) survey of the Kepler field made in 2012 with the Galaxy Evolution Explorer (GALEX) Complete All-Sky UV Survey Extension (CAUSE). The GALEX-CAUSE Kepler survey (GCK) covers 104 square degrees of the Kepler field and reaches a limiting magnitude of NUV~=22.6 at 3{sigma}. Analysis of the GCK survey has yielded a catalog of 660928 NUV sources, of which 475164 are cross-matched with stars in the Kepler Input Catalog. Approximately 327 of 451 confirmed exoplanet host stars and 2614 of 4696 candidate exoplanet host stars identified by Kepler have NUV photometry in the GCK survey. The GCK catalog should enable the identification and characterization of UV-excess stars in the Kepler field (young solar-type and low-mass stars, chromospherically active binaries, white dwarfs, horizontal branch stars, etc.), and elucidation of various astrophysics problems related to the stars and planetary systems in the Kepler field.
- ID:
- ivo://CDS.VizieR/J/ApJ/769/116
- Title:
- Dust-obscured galaxies in the local universe
- Short Name:
- J/ApJ/769/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use Wide-field Infrared Survey Explorer (WISE), AKARI, and Galaxy Evolution Explorer (GALEX) data to select local analogs of high-redshift (z~2) dust obscured galaxies (DOGs). We identify 47 local DOGs with S_12{mu}m_/S_0.22{mu}m_>=892 and S_12{mu}m_>20mJy at 0.05<z<0.08 in the Sloan Digital Sky Survey data release 7. The infrared (IR) luminosities of these DOGs are in the range 3.4x10^10^(L_{sun}_)<~L_IR_<~7.0x10^11^(L_{sun}_) with a median L_IR_ of 2.1x10^11^(L_{sun}_). We compare the physical properties of local DOGs with a control sample of galaxies that have lower S_12{mu}m_/S_0.22{mu}m_ but have similar redshift, IR luminosity, and stellar mass distributions. Both WISE 12{mu}m and GALEX near-ultraviolet (NUV) flux densities of DOGs differ from the control sample of galaxies, but the difference is much larger in the NUV. Among the 47 DOGs, 36%+/-7% have small axis ratios in the optical (i.e., b/a<0.6), larger than the fraction among the control sample (17%+/-3%). There is no obvious sign of interaction for many local DOGs. No local DOGs have companions with comparable optical magnitudes closer than ~50kpc. The large- and small-scale environments of DOGs are similar to the control sample. Many physical properties of local DOGs are similar to those of high-z DOGs, even though the IR luminosities of local objects are an order of magnitude lower than for the high-z objects: the presence of two classes (active galactic nuclei- and star formation-dominated) of DOGs, abnormal faintness in the UV rather than extreme brightness in the mid-IR, and diverse optical morphology. These results suggest a common underlying physical origin of local and high-z DOGs. Both seem to represent the high-end tail of the dust obscuration distribution resulting from various physical mechanisms rather than a unique phase of galaxy evolution.
- ID:
- ivo://CDS.VizieR/J/ApJ/871/258
- Title:
- ELQS in SDSS. III. The full ELQS quasar catalog
- Short Name:
- J/ApJ/871/258
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have designed the Extremely Luminous Quasar Survey (ELQS) to provide a highly complete census of unobscured UV-bright quasars during the cosmic noon, z=2.8-5.0. Here we report the discovery of 70 new quasars in the ELQS South Galactic Cap (ELQS-S) quasar sample, doubling the number of known extremely luminous quasars in 4237.3deg^2^ of the Sloan Digital Sky Survey footprint. These observations conclude the ELQS and we present the properties of the full ELQS quasar catalog, containing 407 quasars over 11838.5deg^2^. Our novel ELQS quasar selection strategy resulted in unprecedented completeness at the bright end and allowed us to discover 109 new quasars in total. This marks an increase of ~36% (109/298) in the known population at these redshifts and magnitudes, while we further are able to retain a selection efficiency of ~80%. On the basis of 166 quasars from the full ELQS quasar catalog, which adhere to the uniform criteria of the Two Micron All Sky Survey point source catalog, we measure the bright-end quasar luminosity function (QLF) and extend it one magnitude brighter than previous studies. Assuming a single power law with exponential density evolution for the functional form of the QLF, we retrieve the best-fit parameters from a maximum likelihood analysis. We find a steep bright-end slope of {beta}~-4.1, and we can constrain the bright-end slope to {beta}<=-3.4 with 99% confidence. The density is well modeled by the exponential redshift evolution, resulting in a moderate decrease with redshift ({gamma}~-0.4).
- ID:
- ivo://CDS.VizieR/J/MNRAS/469/347
- Title:
- Extremely Isolated Galaxies. II.
- Short Name:
- J/MNRAS/469/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have selected a sample of 41 extremely isolated galaxies (EIGs) from the local Universe using both optical and HI Arecibo Legacy Fast ALFA survey redshifts. Narrow-band H{alpha} and wide-band imaging along with public data were used to derive star formation rates (SFRs), star formation histories and morphological classifications for the EIGs. We have found that the extreme isolation of the EIGs does not affect considerably their star formation compared to field galaxies. EIGs are typically 'blue cloud' galaxies that fit the 'main sequence of star-forming galaxies' and may show asymmetric star formation and strong compact star-forming regions. We discovered surprising environmental dependences of the HI content, M_HI_, and of the morphological type of EIGs; the most isolated galaxies (of subsample EIG-1) have lower M_HI_ on average (with 2.5{sigma} confidence) and a higher tendency to be early types (with 0.94 confidence) compared to the less isolated galaxies of subsample EIG-2. To the best of our knowledge, this is the first study that finds an effect in which an isolated sample shows a higher fraction of early types compared to a less isolated sample. Both early-type and late-type EIGs follow the same colour-to-M_*_, SFR-to-M_*_ (main sequence) and M_HI_-to-M_*_ relations. This indicates that the mechanisms and factors governing star formation, colour and the M_HI_-to-M_*_ relation are similar in early-type and late-type EIGs, and that the morphological type of EIGs is not governed by their M_HI_ content, colour or SFR.
- ID:
- ivo://CDS.VizieR/J/A+A/617/A122
- Title:
- GRB 111209A GROND and UVOT light curves
- Short Name:
- J/A+A/617/A122
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Afterglows of Gamma-Ray Bursts (GRBs) are simple in the most basic model, but can show many complex features. The ultra-long duration GRB 111209A, one of the longest GRBs ever detected, also has the best-monitored afterglow in this rare class of GRBs. We want to address the question whether GRB 111209A was a special event beyond its extreme duration alone, and whether it is a classical GRB or another kind of high-energy transient. The afterglow may yield significant clues. We present afterglow photometry obtained in seven bands with the GROND imager as well as in further seven bands with the UVOT telescope on-board the Neil Gehrels Swift Observatory. The light curve is analysed by multi-band modelling and joint fitting with power-laws and broken power-laws, and we use the contemporaneous GROND data to study the evolution of the spectral energy distribution. We compare the optical afterglow to a large ensemble we have analysed in earlier works, and especially to that of another ultra-long event, GRB 130925A. We furthermore undertake a photometric study of the host galaxy. We find a strong, chromatic rebrightening event at ~0.8-days after the GRB, during which the spectral slope becomes redder. After this, the light curve decays achromatically, with evidence for a break at about 9 days after the trigger. The afterglow luminosity is found to not be exceptional. We find that a double-jet model is able to explain the chromatic rebrightening. The afterglow features have been detected in other events and are not unique. The duration aside, the GRB prompt emission and afterglow parameters of GRB 111209A are in agreement with the known distributions for these parameters. While the central engine of this event may differ from that of classical GRBs, there are multiple lines of evidence pointing to GRB 111209A resulting from the core-collapse of a massive star with a stripped envelope.
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