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17381. Wide field imagers ground-based astrometry. V.
ID:
ivo://CDS.VizieR/J/A+A/563/A80
Title:
Wide field imagers ground-based astrometry. V.
Short Name:
J/A+A/563/A80
Date:
21 Oct 2021
Publisher:
CDS
Description:
High-precision astrometry requires accurate point-spread function modeling and accurate geometric-distortion corrections. This paper demonstrates that it is possible to achieve both requirements with data collected at the High Acuity Wide-field K-band Imager (HAWK-I); a wide-field imager installed at the Nasmyth focus of UT4/VLT ESO 8m telescope. Our final astrometric precision reaches ~3mas per coordinate for a well exposed star in a single image, with a systematic error less than 0.1mas. We constructed calibrated astro-photometric catalogs and atlases of 7 fields: the Baade's window, NGC 6656, NGC 6121, NGC 6822, NGC 6388, NGC 104, and the James Webb Space Telescope calibration field (in the LMC). We make these catalogs and images electronically available to the community. Furthermore, as a demonstration of the efficacy of our approach, combining archival material taken with the optical wide-field imager at the MPI/ESO 2.2m with HAWK-I observations, we are able to achieve an excellent separation between cluster members and field objects for NGC 6656 and NGC 6121 with a time base-line of about 8 years. Using both HST and HAWK-I data, we also study the radial distribution of the SGB populations in NGC 6656 and conclude that the radial trend is flat, within our uncertains. We also provide membership probabilities for most of the stars in NGC 6656 and NGC 6121 catalogs and estimate membership for the published variable stars in these two fields.
17382. Wide-field NIR polarimetry of {rho} Oph cloud
ID:
ivo://CDS.VizieR/J/ApJS/220/17
Title:
Wide-field NIR polarimetry of {rho} Oph cloud
Short Name:
J/ApJS/220/17
Date:
21 Oct 2021
Publisher:
CDS
Description:
We conducted wide and deep simultaneous JHK_s_-band imaging polarimetry of the {rho} Ophiuchi cloud complex. Aperture polarimetry in the JHK_s_ band was conducted for 2136 sources in all three bands, of which 322 sources have significant polarizations in all the JHK_s_ bands and have been used for a discussion of the core magnetic fields. There is a positive correlation between degrees of polarization and H-K_s_ color up to H-K_s_~3.5. The magnetic field structures in the core region are revealed up to at least A_V_~47mag and are unambiguously defined in each sub-region (core) of Oph-A, Oph-B, Oph-C, Oph-E, Oph-F, and Oph-AC. Their directions, degrees of polarization, and polarization efficiencies differ but their changes are gradual; thus, the magnetic fields appear to be connected from core to core, rather than as a simple overlap of the different cloud core components. Comparing our results with the large-scale field structures obtained from previous optical polarimetric studies, we suggest that the magnetic field structures in the core were distorted by the cluster formation in this region, which may have been induced by shock compression due to wind/radiation from the Scorpius-Centaurus association.
17383. Wide-field optical imaging of 4 fields
ID:
ivo://CDS.VizieR/J/MNRAS/416/927
Title:
Wide-field optical imaging of 4 fields
Short Name:
J/MNRAS/416/927
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present u-, g-, r-, i- and z-band optical images and associated catalogues taken primarily with the Isaac Newton Telescope Wide Field Camera on the European Large Area ISO Survey (ELAIS) N1 and N2, First Look Survey and Lockman Hole fields comprising a total of 1000h of integration time over 80deg^2^ and approximately 4.3 million objects. In this paper we outline the observations and data processing and characterize the completeness, reliability, photometric and astrometric accuracy of this data set. All images have been photometrically calibrated using the Sloan Digital Sky Survey and a uniform and homogeneous data set is composed over all the observed fields. Magnitude limits are u, g, r, i, z of 23.9, 24.5, 24.0, 23.3, 22.0 (AB, 5{sigma}). These data have been used for optical identification of past and ongoing projects including the surveys ELAIS, Spitzer Wide-Area Infrared Extragalactic Survey, Spitzer Extragalactic Representative Volume Survey and Herschel Multi-tiered Extragalactic Survey.
17384. Wide-field photometry of the GC Palomar 5
ID:
ivo://CDS.VizieR/J/ApJ/819/1
Title:
Wide-field photometry of the GC Palomar 5
Short Name:
J/ApJ/819/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of wide-field photometric surveys of the Palomar 5 globular cluster and its stellar stream, based on g- and r-band measures together with narrow-band DDO 51 photometry. In this first study, we use the deep (g, r) data to measure the incidence of gaps and peaks along the stream. Examining the star-counts profile of the stream plus contaminating populations, we find no evidence for significant underdensities, and find only a single significant overdensity. This is at odds with earlier studies based on matched-filter maps derived from shallower SDSS data if the contaminating population possesses plausible spatial properties. The lack of substantial substructure along the stream may be used in future dynamical simulations to examine the incidence of dark matter sub-halos in the Galactic halo. We also present a measurement of the relative distances along the stream, which we use to create the deepest wide-field map of this system to date. Universe}
17385. Wide Field Planetary Camera 2
ID:
ivo://archive.stsci.edu/hst/wfpc2
Title:
Wide Field Planetary Camera 2
Short Name:
HST.WFPC2
Date:
23 Jul 2020 19:52:01
Publisher:
Space Telescope Science Institute Archive
Description:
The WFPC2 is used to obtain high resolution images of astronomical objects over a relatively wide field of view and a broad range of wavelengths (1150 to 11,000 Å).
17386. Wide Field Planetary Camera 1
ID:
ivo://archive.stsci.edu/hst/wfpc1
Title:
Wide Field Planetary Camera 1
Short Name:
HST.WFPC1
Date:
23 Jul 2020 19:51:30
Publisher:
Space Telescope Science Institute Archive
Description:
The WF/PC-1 was used from April 1990 to November 1993, to obtain high resolution images of astronomical objects over a relatively wide field of view and a broad range of wavelengths (1150 to 11,000 Angstroms).
17387. Wide-Field Plate Database
ID:
ivo://CDS.VizieR/VI/90
Title:
Wide-Field Plate Database
Short Name:
VI/90
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Wide-Field Plate Database (WFPDB) contains the descriptive information for the astronomical wide-field (~>1deg.) photographic observations stored in numerous archives all over the world. When finished it will provide an on-line access to the information for about 2 million observations from nearly 300 archives, obtained since the end of last century. Presently the WFPDB includes data for about 330 000 observations from 57 plate catalogues. About 120 000 observations more from 32 plate catalogs are in preparation to be included in the database. The WFPDB provides for each observation information for the corresponding archive, the parameters of the observational instrument, the observation parameters (position on sky, observation time, object name, method, exposure time, emulsion type, filter type, spectral band, plate size), as well as data on the plate quality, comments, and observers. Data on the plate availability and digitization will be supplemented in the WFPDB in the future.
17388. Wide-Field Plate Database WFPDB
ID:
ivo://org.gavo.dc/wfpdb/q/cone
Title:
Wide-Field Plate Database WFPDB
Short Name:
wfpdb cone
Date:
27 Dec 2024 08:31:03
Publisher:
The GAVO DC team
Description:
The Wide-Field Plate Database (WFPDB_) contains the descriptive information for the astronomical wide-field (>1°) photographic observations stored in numerous archives all over the world. The total number of these observations, obtained since the end of the 19th century with more then 200 instruments (telescopes) is about 2 550 000 from 509 archives. The WFPDB is continually being updated, providing currently access to the information for about 640 000 plates from 117 plate archives (30% of the estimated total number of wide-field plates) .. _WFPDB: http://www.skyarchive.org/
17389. Wide-field spectrosc. survey of GCs in Virgo cluster
ID:
ivo://CDS.VizieR/J/ApJ/835/212
Title:
Wide-field spectrosc. survey of GCs in Virgo cluster
Short Name:
J/ApJ/835/212
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a wide-field spectroscopic survey of globular clusters (GCs) in the Virgo cluster. We obtain spectra for 201 GCs and 55 ultracompact dwarfs (UCDs) using Hectospec on the Multiple-Mirror Telescope and derive their radial velocities. We identify 46 genuine intracluster GCs (IGCs), not associated with any Virgo galaxies, using the 3D GMM test on the spatial and radial velocity distribution. They are located at a projected distance 200kpc<~R<~500kpc from the center of M87. The radial velocity distribution of these IGCs shows two peaks, one at v_r_=1023km/s, associated with the Virgo main body, and another at v_r_=36km/s, associated with the infalling structure. The velocity dispersion of the IGCs in the Virgo main body is {sigma}_GC_~314km/s, which is smoothly connected to the velocity dispersion profile of M87 GCs but is much lower than that of dwarf galaxies in the same survey field, {sigma}_dwarf_~608km/s. The UCDs are more centrally concentrated on massive galaxies-M87, M86, and M84. The radial velocity dispersion of the UCD system is much smaller than that of dwarf galaxies. Our results confirm the large-scale distribution of Virgo IGCs indicated by previous photometric surveys. The color distribution of the confirmed IGCs shows a bimodality similar to that of M87 GCs. This indicates that most IGCs are stripped off dwarf galaxies and some off massive galaxies in the Virgo.
17390. Wide field ugriz photometry of 0.06<z<0.4 AGNs
ID:
ivo://CDS.VizieR/J/ApJ/800/93
Title:
Wide field ugriz photometry of 0.06<z<0.4 AGNs
Short Name:
J/ApJ/800/93
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometry of the large-scale environments of a sample of 12 broad line active galactic nuclei (AGNs) with 0.06<z<0.37 from deep images in the Sloan Digital Sky Survey u, g, r, and i filters taken with the 90Prime prime focus camera on the Steward Observatory Bok Telescope. We measure galaxy clustering around these AGNs using two standard techniques: correlation amplitude (B_gq_) and the two point correlation function. We find average correlation amplitudes for the 10 radio-quiet objects in the sample equal to (9+/-18, 144+/-114, -39+/-56, 295+/-260)Mpc^1.77^ in (u, g, r, i), all consistent with the expectation from galaxy clustering. Using a ratio of the galaxy-quasar cross-correlation function to the galaxy autocorrelation function, we calculate the relative bias of galaxies and AGNs, b_gq_. The bias in the u band, b_gq_=3.08+/-0.51 is larger compared to that calculated in the other bands, but it does not correlate with AGN luminosity, black hole mass, or AGN activity via the luminosity of the [OIII] emission line. Thus ongoing nuclear accretion activity is not reflected in the large scale environments from ~10h^-1^kpc to ~0.5h^-1^Mpc and may indicate a non-merger mode of AGN activity and/or a significant delay between galaxy mergers and nuclear activity in this sample of mostly radio-quiet quasars.

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