- ID:
- ivo://CDS.VizieR/J/A+A/526/A21
- Title:
- Collinder 69 X-ray sources
- Short Name:
- J/A+A/526/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first paper of a series devoted to the {lambda} Orionis star-forming region, Orion's Head, from the X-ray perspective. Our final aim is to provide a comprehensive view of this complex region, which includes several distinct associations and dark clouds. We aim to uncover the population of the central, young star cluster Collinder 69, and in particular those diskless Class III objects not identified by previous surveys based on near- and mid-infrared searches, and to establish the X-ray luminosity function for the association.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/720/368
- Title:
- Color-magnitude relations of galaxies in CDFs
- Short Name:
- J/ApJ/720/368
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We extend color-magnitude relations for moderate-luminosity X-ray active galactic nucleus (AGN) hosts and non-AGN galaxies through the galaxy formation epoch (z~1-4) in the Chandra Deep Field-North and Chandra Deep Field-South (CDF-N and CDF-S, respectively; jointly CDFs) surveys. This study was enabled by the deepest available X-ray data from the 2Ms CDF surveys as well as complementary ultradeep multiwavelength data in these regions. We utilized analyses of color-magnitude diagrams (CMDs) to assess the role of moderate-luminosity AGNs in galaxy evolution.
- ID:
- ivo://CDS.VizieR/II/84
- Title:
- 13-color photometry of 1380 bright stars
- Short Name:
- II/84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue contains observations of essentially all stars brighter than fifth visual magnitude north of declination -20 degrees and brighter than fourth visual magnitude south of declination -20 degrees, in the 13-color medium-narrow-band photometric system.
- ID:
- ivo://CDS.VizieR/J/A+A/389/641
- Title:
- Colors of Minor Bodies in the Outer Solar System
- Short Name:
- J/A+A/389/641
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a compilation of all available colors for 104 Minor Bodies in the Outer Solar System (MBOSSes); for each object, the original references are listed. The measurements were combined in a way that does not introduce rotational color artifacts. We then derive the slope, or reddening gradient, of the low resolution reflectance spectra obtained from the broad-band color for each object. A set of color-color diagrams, histograms and cumulative probability functions are presented as a reference for further studies, and are discussed.
- ID:
- ivo://CDS.VizieR/J/ApJS/243/12
- Title:
- Colors of the Outer Solar System Origins Survey
- Short Name:
- J/ApJS/243/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Colours of the Outer Solar System Origins Survey is acquiring near-simultaneous g, r, and J photometry of unprecedented precision with the Gemini North Telescope, targeting nearly 100 trans-Neptunian objects (TNOs) brighter than m_r_=23.6mag discovered in the Outer Solar System Origins Survey. Combining the optical and near-infrared photometry with the well-characterized detection efficiency of the Colours of the Outer Solar System Origins Survey target sample will provide the first flux-limited compositional dynamical map of the outer solar system. In this paper, we describe our observing strategy and detail the data reduction processes we employ, including techniques to mitigate the impact of rotational variability. We present optical and near-infrared colors for 35 TNOs. We find two taxonomic groups for the dynamically excited TNOs, the neutral and red classes, which divide at g-r~0.75. Based on simple albedo and orbital distribution assumptions, we find that the neutral class outnumbers the red class, with a ratio of 4:1 and potentially as high as 11:1. Including in our analysis constraints from the cold classical objects, which are known to exhibit unique albedos and r-z colors, we find that within our measurement uncertainty our observations are consistent with the primordial solar system protoplanetesimal disk being neutral class dominated, with two major compositional divisions in grJ color space.
- ID:
- ivo://CDS.VizieR/J/AJ/119/1424
- Title:
- Color-temperature relations of M giants
- Short Name:
- J/AJ/119/1424
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of a project to model the integrated spectra and colors of elliptical galaxies through evolutionary synthesis, we have refined our synthetic spectrum calculations of M giants. After critically assessing three effective temperature scales for M giants, we adopted the relation of Dyck et al. for our models. Using empirical spectra of field M giants as a guide, we then calculated MARCS stellar atmosphere models (Gustafsson et al. 1975; Bell et al. 1976) and SSG synthetic spectra (Bell & Gustafsson 1978; Gustafsson & Bell 1979) of these cool stars, adjusting the band absorption oscillator strengths of the TiO bands to better reproduce the observational data. The resulting synthetic spectra are found to be in very good agreement with the K-band spectra of stars of the appropriate spectral type taken from Kleinmann & Hall (1986) as well. Spectral types estimated from the strengths of the TiO bands and the depth of the band head of CO near 2.3 {mu}m quantitatively confirm that the synthetic spectra are good representations of those of field M giants. The broadband colors of the models match the field relations of K and early-M giants very well; for late-M giants, differences between the field star and synthetic colors are probably caused by the omission of spectral lines of VO and H_2_O in the spectrum synthesis calculations. Here, we present four grids of K-band bolometric corrections and colors - Johnson U-V and B-V, Cousins V-R and V-I, Johnson-Glass V-K, J-K, and H-K, and CIT/CTIO V-K, J-K, H-K, and CO - for models having 3000 K {<=} Teff {<=} 4000 K and -0.5 {<=} log(g) {<=} 1.5.
- ID:
- ivo://CDS.VizieR/J/AN/333/60
- Title:
- Colour indices of selected OB stars
- Short Name:
- J/AN/333/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have applied the method of investigating extinction curves using statistically meaningful samples that was proposed by us 25 years ago. The extensive data sets of the ANS (Astronomical Netherlands Satellite) and 2MASS (Two Micron All Sky Survey) were used, together with UBV photometry to create average extinction curves for samples of OB stars. Our results demonstrate that in the vast majority of cases the extinction curves are very close to the mean galactic extinction curve. Only a few objects were found to be obviously discrepant from the average. The latter phenomenon may be related to nitrogen chemistry in translucent interstellar clouds.
- ID:
- ivo://CDS.VizieR/J/ApJ/623/181
- Title:
- Compact high-velocity cloud photometry catalog
- Short Name:
- J/ApJ/623/181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of a photometric search for giant stars associated with the cores of four high-velocity clouds (HVCs) - two of which are compact HVCs - using the Las Campanas du Pont 2.5m and Cerro Tololo Blanco 4m telescopes in combination with a system of filters (Washington M, T_2_ + DDO51) useful for identifying low surface gravity, evolved stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/807/23
- Title:
- Companions of RS CVn primaries. I. sig Gem
- Short Name:
- J/ApJ/807/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To measure the properties of both components of the RS Canum Venaticorum binary {sigma} Geminorum ({sigma} Gem), we directly detect the faint companion, measure the orbit, obtain model-independent masses and evolutionary histories, detect ellipsoidal variations of the primary caused by the gravity of the companion, and measure gravity darkening. We detect the companion with interferometric observations obtained with the Michigan InfraRed Combiner at Georgia State University's Center for High Angular Resolution Astronomy Array with a primary-to-secondary H-band flux ratio of 270+/-70. A radial velocity curve of the companion was obtained with spectra from the Tillinghast Reflector Echelle Spectrograph on the 1.5m Tillinghast Reflector at Fred Lawrence Whipple Observatory. We additionally use new observations from the Tennessee State University Automated Spectroscopic and Photometric Telescopes (AST and APT, respectively). From our orbit, we determine model-independent masses of the components (M1=1.28+/-0.07M_{sun}_, M2=0.73+/-0.03M_{sun}_), and estimate a system age of 5+/-1Gyr. An average of the 27 year APT light curve of {sigma} Gem folded over the orbital period (P=19.6027+/-0.0005days) reveals a quasi-sinusoidal signature, which has previously been attributed to active longitudes 180{deg} apart on the surface of {sigma} Gem. With the component masses, diameters, and orbit, we find that the predicted light curve for ellipsoidal variations due to the primary star partially filling its Roche lobe potential matches well with the observed average light curve, offering a compelling alternative explanation to the active longitudes hypothesis. Measuring gravity darkening from the light curve gives {beta}<0.1, a value slightly lower than that expected from recent theory.
- ID:
- ivo://CDS.VizieR/J/AJ/160/131
- Title:
- Compilation of 289 eclipsing binaries parameters
- Short Name:
- J/AJ/160/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate directly imaging exoplanets around eclipsing binaries using the eclipse as a natural tool for dimming the binary and thus increasing the planet to star brightness contrast. At eclipse, the binary becomes pointlike, making coronagraphy possible. We select binaries where the planet-star contrast would be boosted by >10x during eclipse, making it possible to detect a planet that is >~10x fainter or in a star system that is ~2-3x more massive than otherwise. Our approach will yield insights into planet occurrence rates around binaries versus individual stars. We consider both self-luminous (SL) and reflected light (RL) planets. In the SL case, we select binaries whose age is young enough so that an orbiting SL planet would remain luminous; in U Cep and AC Sct, respectively, our method is sensitive to SL planets of ~4.5 and ~9 M_J_ with current ground- or near-future space-based instruments and ~1.5 and ~6 M_J_ with future ground-based observatories. In the RL case, there are three nearby (<~50 pc) systems-V1412 Aql, RR Cae, and RT Pic-around which a Jupiter-like planet at a planet-star separation of >~20mas might be imaged with future ground- and space-based coronagraphs. A Venus-like planet at the same distance might be detectable around RR Cae and RT Pic. A habitable Earth-like planet represents a challenge; while the planet-star contrast at eclipse and planet flux are accessible with a 6-8m space telescope, the planet-star separation is 1/3-1/4 of the angular separation limit of modern coronagraphy.
