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791. [NeII] emission line observations from SgrA West
ID:
ivo://CDS.VizieR/J/ApJ/755/90
Title:
[NeII] emission line observations from SgrA West
Short Name:
J/ApJ/755/90
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new observations of the [NeII] emission from the ionized gas in Sgr A West with improved resolution and sensitivity. About half of the emission comes from gas with kinematics indicating it is orbiting in a plane tipped about 25{deg} from the Galactic plane. This plane is consistent with that derived previously for the circumnuclear molecular disk and the northern arm and western arc ionized features. However, unlike most previous studies, we conclude that the ionized gas is not moving along the ionized features, but on more nearly circular paths. The observed speeds are close to, but probably somewhat less than expected for orbital motions in the potential of the central black hole and stars and have a small inward component. The spatial distribution of the emission is well fitted by a spiral pattern. We discuss possible physical explanations for the spatial distribution and kinematics of the ionized gas, and conclude that both may be best explained by a one-armed spiral density wave, which also accounts for both the observed low velocities and the inward velocity component. We suggest that a density wave may result from the precession of elliptical orbits in the potential of the black hole and stellar mass distribution.
792. NEOWISE 2-Band Post-Cryo Single Exposure (L1b) Known Solar System Object Possible Association List
ID:
ivo://irsa.ipac/WISE/Catalog/2-Band/SSOPAL
Title:
NEOWISE 2-Band Post-Cryo Single Exposure (L1b) Known Solar System Object Possible Association List
Short Name:
WISE 2-Band SSO
Date:
01 Oct 2018 20:27:16
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The NEOWISE Post-Cryo Data Release products were generated using data taken during the mission's Post-Cryo survey phase. This phase covers the time following the exhaustion of solid hydrogen in the WISE payload inner cryogen tank, when the detectors and optics gradually warmed until they reached a stable equilibrium temperature near 73.5 K. During this time, WISE's W1 and W2 detectors continued to acquire high quality imaging data with sensitivities close to that during the mission's cryogenic survey phases. The W3 and W4 detectors were fully saturated by the thermal emission from the warming telescope. WISE scanned approximately 70% of the sky during the Post-Cryo survey phase continuing with the same strategy that was used during the full cryogenic survey. The Known Solar System Object Possible Associations List is a compendium of asteroids and comets, with orbits known at the time of WISE second-pass data processing, that were predicted to be within the field-of-view at the time of individual WISE exposures. Individual objects were observed multiple times, so may have multiple entries in the list. When the predicted position of a solar system object is in proximity to a detection in the WISE single-exposures, the WISE source position and brightness information are also provided.
793. NEOWISE 2-Band Post-Cryo Single Exposure (L1b) Source Table
ID:
ivo://irsa.ipac/WISE/Catalog/2-Band/SingleExpSourceTbl
Title:
NEOWISE 2-Band Post-Cryo Single Exposure (L1b) Source Table
Short Name:
WISE 2-Band ST
Date:
01 Oct 2018 20:27:16
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The NEOWISE Post-Cryo Single-exposure Source Database contains 7,337,642,955 measurements of positions and brightness information, uncertainties, time of observation and assorted quality flags made on the individual WISE 7.7s (W1 and W2) Single-exposure images. Because WISE scanned every point on the sky multiple times, the Single-exposure Database contains multiple, independent measurements of objects on the sky. Entries in the Single-exposure Source Database include detections of real astrophysical objects, as well as spurious detections of low SNR noise excursions, transient events such as hot pixels, charged particle strikes and satellite streaks, and image artifacts light from bright sources including the moon. Many of the unreliable detections are flagged in the Single-exposure Database, but they have not been filtered out as they were for the All-Sky Release Source Catalog. Therefore, the Database must be used with caution. Users are strongly encouraged to read the Cautionary Notes before using the Database.
794. NEOWISE observations of NEOs: preliminary results
ID:
ivo://CDS.VizieR/J/ApJ/743/156
Title:
NEOWISE observations of NEOs: preliminary results
Short Name:
J/ApJ/743/156
Date:
21 Oct 2021
Publisher:
CDS
Description:
With the NEOWISE portion of the Wide-field Infrared Survey Explorer (WISE) project, we have carried out a highly uniform survey of the near-Earth object (NEO) population at thermal infrared wavelengths ranging from 3 to 22um, allowing us to refine estimates of their numbers, sizes, and albedos. The NEOWISE survey detected NEOs the same way whether they were previously known or not, subject to the availability of ground-based follow-up observations, resulting in the discovery of more than 130 new NEOs. The survey's uniform sensitivity, observing cadence, and image quality have permitted extrapolation of the 428 near-Earth asteroids (NEAs) detected by NEOWISE during the fully cryogenic portion of the WISE mission to the larger population. We find that there are 981+/-19 NEAs larger than 1km and 20500+/-3000 NEAs larger than 100m. We show that the Spaceguard goal of detecting 90% of all 1km NEAs has been met, and that the cumulative size distribution is best represented by a broken power law with a slope of 1.32+/-0.14 below 1.5km. This power-law slope produces ~13200+/-1900 NEAs with D>140m. Although previous studies predict another break in the cumulative size distribution below D~50-100m, resulting in an increase in the number of NEOs in this size range and smaller, we did not detect enough objects to comment on this increase. The overall number for the NEA population between 100 and 1000m is lower than previous estimates. The numbers of near-Earth comets and potentially hazardous NEOs will be the subject of future work.
795. NEOWISE-R Known Solar System Object Possible Association List
ID:
ivo://irsa.ipac/WISE/Catalog/NEOWISE-R/SSOPAL
Title:
NEOWISE-R Known Solar System Object Possible Association List
Short Name:
NEOWISE-R SSOPAL
Date:
01 Oct 2018 20:27:16
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The Near-Earth Object Wide-field Infrared Survey Explorer Reactivation Mission (NEOWISE; Mainzer et al. 2014, ApJ, 792, 30) is a NASA Planetary Science Division space-based survey to detect, track and characterize asteroids and comets, and to learn more about the population of near-Earth objects that could pose an impact hazard to the Earth. NEOWISE systematically images the sky at 3.4 and 4.6 μm, obtaining multiple independent observations on each location that enable detection of previously known and new solar system small bodies by virtue of the their motion. Because it is an infrared survey, NEOWISE detects asteroid thermal emission and is equally sensitive to high and low albedo objects. The Known Solar-System Object Possible Associations List is a compendium of asteroids, comets, planets or planetary satellites, with orbits known at the time of NEOWISE data processing, that were predicted to be within the field-of-view at the time of individual NEOWISE Single-exposures. Individual objects were observed multiple times, so may have multiple entries in the list. When the predicted position of a solar system object is in proximity to a detection in the NEOWISE Single-exposures, the NEOWISE detection position and brightness information are also provided.
796. NEOWISE-R Single Exposure (L1b) Frame Metadata Table
ID:
ivo://irsa.ipac/WISE/Catalog/NEOWISE-R/Frame_Metadata
Title:
NEOWISE-R Single Exposure (L1b) Frame Metadata Table
Short Name:
NEOWISE-R Meta
Date:
01 Oct 2018 20:27:16
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The Near-Earth Object Wide-field Infrared Survey Explorer Reactivation Mission (NEOWISE; Mainzer et al. 2014, ApJ, 792, 30) is a NASA Planetary Science Division space-based survey to detect, track and characterize asteroids and comets, and to learn more about the population of near-Earth objects that could pose an impact hazard to the Earth. NEOWISE systematically images the sky at 3.4 and 4.6 μm, obtaining multiple independent observations on each location that enable detection of previously known and new solar system small bodies by virtue of the their motion. Because it is an infrared survey, NEOWISE detects asteroid thermal emission and is equally sensitive to high and low albedo objects. The following table contains brief descriptions of all metadata information that is relevant to the processing of Single-exposure (level 1) images and the extraction of sources from the corresponding Single-exposure images. The table contains the unique scan ID and frame number for specific each single-exposure image and the reconstructed right ascension and declination of the image center. Much of the information in this table is processing-specific, and may not be of interest to general users (e.g. flags indicating whether frames have been processed or not, and the date and time for starting of the pipeline etc). The metadata table also contains some characterization and derived statistics of the Single-exposure image frames, basic parameters used for photometry and derived statistics for extracted sources and artifacts. For example, it contains the number of sources with profile-fit photometry Signal-to-Noise (SNR) greater than 3, and the total number of real sources affected by artifacts such as latent images and electronic ghosts.
797. NEOWISE-R Single Exposure (L1b) Source Table
ID:
ivo://irsa.ipac/WISE/Catalog/NEOWISE-R/Source_Table
Title:
NEOWISE-R Single Exposure (L1b) Source Table
Short Name:
NEOWISE-R ST
Date:
01 Oct 2018 20:27:16
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The Near-Earth Object Wide-field Infrared Survey Explorer Reactivation Mission (NEOWISE; Mainzer et al. 2014, ApJ, 792, 30) is a NASA Planetary Science Division space-based survey to detect, track and characterize asteroids and comets, and to learn more about the population of near-Earth objects that could pose an impact hazard to the Earth. NEOWISE systematically images the sky at 3.4 and 4.6 μm, obtaining multiple independent observations on each location that enable detection of previously known and new solar system small bodies by virtue of the their motion. Because it is an infrared survey, NEOWISE detects asteroid thermal emission and is equally sensitive to high and low albedo objects. The Single-exposure Source Database is a compendium of position and flux information for source detections made on the individual NEOWISE 7.7s W1 and W2 Single-exposure images. Because NEOWISE scanned the same region of the sky multiple times, the Single-exposure Database contains multiple, independent measurements of objects. Positions, magnitudes in the two NEOWISE bands, astrometric and photometric uncertainties, flags indicating measurement quality, the time of observations and associations with the AllWISE Source Catalog and 2MASS Point Source Catalog are presented for entries in the Database.
798. NEP raster ROSAT X-ray/Optical catalog
ID:
ivo://CDS.VizieR/J/A+A/645/A95
Title:
NEP raster ROSAT X-ray/Optical catalog
Short Name:
J/A+A/645/A95
Date:
21 Oct 2021
Publisher:
CDS
Description:
The North-Ecliptic Pole is an important region for extragalactic surveys. Deep/wide contiguous surveys are being performed by several space observatories. We analyse all ROSAT pointed and survey observations within 40deg^2^ around the NEP, restricting the field-of-view to the inner 30' radius. We obtain an X-ray catalogue of 805 sources with 0.5-2keV fluxes >2.9*10^-15^erg/cm^2^/s, a factor of three deeper than the ROSAT All-Sky Survey in this field. The sensitivity and angular resolution of our data are comparable to the eROSITA All-Sky Survey expectations. The 50% position error radius of the sample of X-ray sources is ~10". We use HEROES optical and near-infrared imaging photometry from Subaru and CFHT telescopes together with literature catalogues and a new deep and wide Spitzer survey in the field to identify X-ray sources and calculate photometric redshifts for the candidate counterparts. In particular we utilize mid-IR colours to identify AGN X-ray counterparts. Despite relatively large error circles and faint counterparts, confusion and systematic errors, we obtain a rather reliable catalogue of 766 optical counterparts, redshifts and optical classifications. We find a new population of luminous absorbed X-ray AGN at large redshifts, not recognized in previous X-ray surveys, but identified in our work due to the unique combination of survey solid angle, X-ray sensitivity and multiwavelength photometry. We also use the WISE and Spitzer photometry to identify a sample of 185 AGN selected purely through mid-IR colours, most of which are not detected by ROSAT. Their redshifts and upper limits to X-ray luminosity and X-ray-to-optical flux ratios are even higher than for the new class of X-ray selected luminous type 2 AGN (AGN2); they are probably a natural extension of this sample. This unique dataset is important as a reference sample for future deep surveys in the NEP region, in particular for eROSITA and also for Euclid and SPHEREX. We predict that most of the absorbed distant AGN should be readily picked up by eROSITA, but they require sensitive mid-IR imaging to be recognized as optical counterparts.
799. New AO obs. of exoplanets & brown dwarf companions
ID:
ivo://CDS.VizieR/J/AJ/159/63
Title:
New AO obs. of exoplanets & brown dwarf companions
Short Name:
J/AJ/159/63
Date:
21 Oct 2021
Publisher:
CDS
Description:
The orbital eccentricities of directly imaged exoplanets and brown dwarf companions provide clues about their formation and dynamical histories. We combine new high-contrast imaging observations of substellar companions obtained primarily with Keck/NIRC2 together with astrometry from the literature to test for differences in the population-level eccentricity distributions of 27 long-period giant planets and brown dwarf companions between 5 and 100au using hierarchical Bayesian modeling. Orbit fits are performed in a uniform manner for companions with short orbital arcs; this typically results in broad constraints for individual eccentricity distributions, but together as an ensemble, these systems provide valuable insight into their collective underlying orbital patterns. The shape of the eccentricity distribution function for our full sample of substellar companions is approximately flat from e=0-1. When subdivided by companion mass and mass ratio, the underlying distributions for giant planets and brown dwarfs show significant differences. Low mass ratio companions preferentially have low eccentricities, similar to the orbital properties of warm Jupiters found with radial velocities and transits. We interpret this as evidence for in situ formation on largely undisturbed orbits within massive extended disks. Brown dwarf companions exhibit a broad peak at e~0.6-0.9 with evidence for a dependence on orbital period. This closely resembles the orbital properties and period-eccentricity trends of wide (1-200au) stellar binaries, suggesting that brown dwarfs in this separation range predominantly form in a similar fashion. We also report evidence that the "eccentricity dichotomy" observed at small separations extends to planets on wide orbits: the mean eccentricity for the multi-planet system HR8799 is lower than for systems with single planets. In the future, larger samples and continued astrometric orbit monitoring will help establish whether these eccentricity distributions correlate with other parameters such as stellar host mass, multiplicity, and age.
800. New brown dwarfs in upper Sco
ID:
ivo://CDS.VizieR/J/MNRAS/418/1231
Title:
New brown dwarfs in upper Sco
Short Name:
J/MNRAS/418/1231
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the results of a search for brown dwarfs in the Upper Scorpius Association using data from the UKIRT Infrared Deep Sky Survey (UKIDSS) Galactic Cluster Survey. Candidate young brown dwarfs were first chosen by their position in colour magnitude diagrams with further selection based on proper motions to ensure Upper Scorpius membership. Proper motions were derived by comparing UKIDSS and Two Micron All Sky Survey (2MASS) data. Using that method we identify 19 new brown dwarfs in the southern part of the association. In addition there are up to eight likely members with slightly higher dispersion velocity. The ratio of brown dwarfs to stars was found to be consistent with other areas in Upper Scorpius. It was also found to be similar to other results from young clusters with OB associations, and lower than those without, suggesting the brown dwarf formation rate may be a function of environment.