- ID:
- ivo://CDS.VizieR/J/MNRAS/439/1212
- Title:
- Deep 20GHz survey of CDFS and SDSS Stripe 82
- Short Name:
- J/MNRAS/439/1212
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a source catalogue and first results from a deep, blind radio survey carried out at 20GHz with the Australia Telescope Compact Array, with follow-up observations at 5.5, 9 and 18GHz. The Australia Telescope 20GHz (AT20G) deep pilot survey covers a total area of 5deg^2^ in the Chandra Deep Field South and in Stripe 82 of the Sloan Digital Sky Survey. We estimate the survey to be 90% complete above 2.5mJy. Of the 85 sources detected, 55percent have steep spectra ({alpha}_1.4_^20^<-0.5) and 45% have flat or inverted spectra ({alpha}_1.4_^20^>=-0.5). The steep-spectrum sources tend to have single power-law spectra between 1.4 and 18GHz, while the spectral indices of the flat- or inverted-spectrum sources tend to steepen with frequency. Among the 18 inverted-spectrum ({alpha}_1.4_^20^>=0.0) sources, 10 have clearly defined peaks in their spectra with {alpha}_1.4_^5.5^>0.15 and {alpha}_9_^18^<-0.15. On a 3-yr time-scale, at least 10 sources varied by more than 15percent at 20GHz, showing that variability is still common at the low flux densities probed by the AT20G-deep pilot survey.
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- ID:
- ivo://CDS.VizieR/J/ApJS/150/417
- Title:
- Deep, high-resolution survey at 74MHz
- Short Name:
- J/ApJS/150/417
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 74MHz survey of a 165deg^2^ region located near the north Galactic pole. This survey has an unprecedented combination of both resolution (25" FWHM) and sensitivity ({sigma} as low as 24mJy/beam). We detect 949 sources at the 5{sigma} level in this region, enough to begin exploring the nature of the 74MHz source population. We present differential source counts, spectral index measurements, and the size distribution as determined from counterparts in the high-resolution FIRST 1.4GHz survey, Cat. <VIII/71>.
- ID:
- ivo://archive.stsci.edu/catalogs/HLSP_47TUC
- Title:
- Deep Imaging of 47 Tuc Catalog ConeSearch
- Short Name:
- 47 TUC CS
- Date:
- 23 Jul 2020 20:41:29
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- Kalirai et al. have observed the globular cluster 47 Tucanae for 121 orbits using the Advanced Camera for Surveys. These extremely deep images were taken in two filters: F606W (broad V-band) and F814W (I-band). Using these observations, Kalirai et al. were able to construct one of the deepest and most complete color-magnitude diagrams of a stellar population, probing down to 30th magnitude and extending from the faintest end of the main sequence to the coolest white dwarf members. As an added bonus, members of the Small Magellanic Cloud represent background sources, and these observations are able to resolve SMC targets down to 0.2 solar masses. The team have released their stacked ACS mosaics (FITS files), source catalog (ASCII text table), and artificial source lists (ASCII text table) used for testing photometry, astrometry, and completeness, as High Level Science Products. We summarize the creation of the stacked images and generation of the catalogs below, but refer you to the original publication for complete details. All available catalogs are listed at http://archive.stsci.edu/vo/mast_services.html.
- ID:
- ivo://CDS.VizieR/J/ApJ/743/64
- Title:
- Deep infrared photometry of {sigma} Ori cluster
- Short Name:
- J/ApJ/743/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a deep I, Z photometric survey covering a total area of 1.12deg^2^ of the {sigma} Orionis cluster and reaching completeness magnitudes of I=22 and Z=21.5mag. From I, I-Z color-magnitude diagrams we have selected 153 candidates that fit the previously known sequence of the cluster. They have magnitudes in the range I=16-23mag, which corresponds to a mass interval from 0.1 down to 0.008M_{sun}_ at the most probable age of {sigma} Orionis (2-4Myr). Using J-band photometry, we find that 124 of the 151 candidates within the completeness of the optical survey (82%) follow the previously known infrared photometric sequence of the cluster and are probably members. We have studied the spatial distribution of the very low mass stars and brown dwarf population of the cluster and found that there are objects located at distances greater than 30 arcmin to the north and west of {sigma} Orionis that probably belong to different populations of the Orion's Belt. For the 102 bona fide {sigma} Orionis cluster member candidates, we find that the radial surface density can be represented by a decreasing exponential function ({sigma}={sigma}_0_e^-r/r_0_^) with a central density of {sigma}_0_=0.23+/-0.03 objects arcmin^-2^ and a characteristic radius of r_0_=9.5+/-0.7 arcmin. Using near-infrared JHK-band data from Two Micron All Sky Survey and UKIRT Deep Infrared Sky Survey and mid-infrared data from Infrared Array Camera/Spitzer, we find that about 5%-9% of the brown dwarf candidates in the {sigma} Orionis cluster have K-band excesses and 30%+/-7% of them show mid-infrared excesses at wavelengths longer than 5.8um. These are probably related to the presence of disks, most of which are "transition disks".
- ID:
- ivo://CDS.VizieR/J/MNRAS/383/75
- Title:
- Deep 610MHz survey of ELAIS-N1 sources
- Short Name:
- J/MNRAS/383/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of the ELAIS-N1 field taken at 610MHz with the Giant Metrewave Radio Telescope are presented. Nineteen pointings were observed, covering a total area of 9 square degrees with a resolution of 6x5arcsec^2^, PA=45deg. Four of the pointings were deep observations with an rms of ~40uJy before primary beam correction, with the remaining fifteen pointings having an rms of ~70uJy. The techniques used for data reduction and production of a mosaicked image of the region are described, and the final mosaic, along with a catalogue of 2500 sources detected above 6{sigma}, are presented. This work complements the large amount of optical and infrared data already available on the region. For further details of the surveys and data analysis procedures please refer to the published paper.
- ID:
- ivo://CDS.VizieR/J/ApJS/119/189
- Title:
- Deep Multicolor Survey. IV.
- Short Name:
- J/ApJS/119/189
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This stellar catalog contains 19,494 objects from the Deep Multicolor Survey (DMS) and results from follow-up spectroscopic observations of 234 objects in the catalog. The DMS is based on CCD imaging with the Mayall 4 m telescope in U, B, V, R', I75, and I86 and covers 0.83 deg^2 in six fields at high Galactic latitude. The survey reached 5 sigma limiting magnitudes of 22.1 in I86 to 23.8 in B. The catalog gives positions, magnitudes and error estimates, and classification codes in the six filter bands for all the objects. In addition, the survey is useful for the study of faint field galaxies and of faint stars at high Galactic latitude. Presented are tables that summarize the spectroscopic results for the 55 quasars, 44 compact narrow emission-line galaxies, and 135 stars in the DMS that we have confirmed to date. Also included are illustrations of all the spectra.
- ID:
- ivo://CDS.VizieR/J/ApJ/725/2232
- Title:
- Deep NIR survey of the Pipe Nebula. II.
- Short Name:
- J/ApJ/725/2232
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new set of high-resolution dust extinction maps of the nearby and essentially starless Pipe Nebula molecular cloud. The maps were constructed from a concerted deep near-infrared imaging survey with the ESO-VLT, ESO-NTT, CAHA 3.5m telescopes, and 2MASS data. The new maps have a resolution three times higher than the previous extinction map of this cloud by Lombardi et al. (2006A&A...454..781L) and are able to resolve structures down to 2600AU. We detect 244 significant extinction peaks across the cloud. These peaks have masses between 0.1 and 18.4M_{sun}_, diameters between 1.2 and 5.7x10^4^AU (0.06 and 0.28pc), and mean densities of about 10^4^cm^-3^, all in good agreement with previous results. From the analysis of the mean surface density of companions we find a well-defined scale near 1.4x10^4^AU below which we detect a significant decrease in structure of the cloud. This scale is smaller than the Jeans length calculated from the mean density of the peaks. The surface density of peaks is not uniform but instead it displays clustering. Extinction peaks in the Pipe Nebula appear to have a spatial distribution similar to the stars in Taurus, suggesting that the spatial distribution of stars evolves directly from the primordial spatial distribution of high-density material.
- ID:
- ivo://CDS.VizieR/J/ApJS/219/21
- Title:
- Deep NIR survey toward Aquila. I. MHOs
- Short Name:
- J/ApJS/219/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed an unbiased, deep near-infrared survey toward the Aquila molecular cloud with a sky coverage of ~1deg^2^. We identified 45 molecular hydrogen emission-line objects (MHOs), of which only 11 were previously known. Using the Spitzer archival data, we also identified 802 young stellar objects (YSOs) in this region. Based on the morphology and the location of MHOs and YSO candidates, we associate 43 MHOs with 40 YSO candidates. The distribution of jet length shows an exponential decrease in the number of outflows with increasing length, and the molecular hydrogen outflows seem to be oriented randomly. Moreover, there is no obvious correlation between jet lengths, jet opening angles, or jet H_2_ 1-0 S(1) luminosities and the spectral indices of the possible driving sources in this region. We also suggest that molecular hydrogen outflows in the Aquila molecular cloud are rather weak sources of turbulence, unlikely to generate the observed velocity dispersion in the region of survey.
- ID:
- ivo://CDS.VizieR/III/113A
- Title:
- Deep Objective-Prism Survey for LMC Members
- Short Name:
- III/113A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains 1273 proven or probable Large Magellanic Cloud (LMC) members, identified on plates taken with the Curtis-Schmidt telescope at Cerro Tololo Inter-American Observatory in Chile. The stars are generally brighter than photographic magnitude 14 and are identified on charts published by Hodge and Wright (1967) and reproduced in the source publication (1970CoTol..89....1S). Approximate spectral types were determined by examination of the 580 Angstroms/mm (at H{gamma}) objective-prism spectra; approximate 1975 positions were obtained by measuring relative to the 1975 coordinate grids on the Uppsala-Mount Stromlo Atlas of the LMC (Gascoigne and Westerlund 1961), and approximate photographic magnitudes were determined by averaging image density measures from the plates and image-diameter measures on the "B" charts of Hodge and Wright (1967SAOP.4699....1H). The catalog includes an identification number (Sk), HD(E) number, Cape Photographic Durchmusterung number, right ascension and declination (equinox B1975), spectral type, photographic magnitude, and alternate identifications. The machine version, updated in September 1986, includes corrections supplied by the author in 1985; thus, it differs somewhat from the published version. Accurate positions, and cross-identifications with the modern surveys, were determined by Brian Skiff in 2008, and make up the "sk_pos.dat" file. This work is based on a file prepared through great effort by Mati Morel in 1999. Brian Skiff examined every object on DSS cut-outs to make sure the star chosen matched the Sanduleak charts. The Goddard SkyView utility was used, looking at an 0.07{deg} (4'x4') field from the DSS1 (short-V plate), DSS2 far-red, and 2MASS J-band images. These three have the shallowest effective exposure (these are bright stars!), and usually the best image quality to check for companions etc as well as star colors. Precise coordinates were then obtained via VizieR mainly from UCAC2, but occasionally elsewhere as indicated in the column 's' for each star. The list was also matched against Tycho-2 and the GSC, and the Massey et al. photometric survey from 2002ApJS..141...81M (Cat. II/236). The file "sk_pos.dat" includes also Sanduleak's original approximate spectral types, and approximative V magnitudes that Mati Morel adopted from the work of the Marseille group; some missing HD(E) and CPD names were also added. It should be noticed also that the file has 1275 entries, 3 stars being resolved into resolved pairs. The notes includes Sanduleak's original notes, as well as remarks added by Brian Skiff in the course of his verifications.
- ID:
- ivo://CDS.VizieR/J/ApJS/218/9
- Title:
- Deep XMM-Newton survey of M33
- Short Name:
- J/ApJS/218/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained a deep 8 field XMM-Newton mosaic of M33 covering the galaxy out to the D_25_ isophote and beyond to a limiting 0.2-4.5keV unabsorbed flux of 5x10^-16^erg/cm2/s (L>4x10^34^erg/s at the distance of M33). These data allow complete coverage of the galaxy with high sensitivity to soft sources such as diffuse hot gas and supernova remnants (SNRs). Here, we describe the methods we used to identify and characterize 1296 point sources in the 8 fields. We compare our resulting source catalog to the literature, note variable sources, construct hardness ratios, classify soft sources, analyze the source density profile, and measure the X-ray luminosity function (XLF). As a result of the large effective area of XMM-Newton below 1keV, the survey contains many new soft X-ray sources. The radial source density profile and XLF for the sources suggest that only ~15% of the 391 bright sources with L>3.6x10^35^erg/s are likely to be associated with M33, and more than a third of these are known SNRs. The log(N)-log(S) distribution, when corrected for background contamination, is a relatively flat power law with a differential index of 1.5, which suggests that many of the other M33 sources may be high-mass X-ray binaries. Finally, we note the discovery of an interesting new transient X-ray source, which we are unable to classify.
