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1121. 610-MHz survey of Lockman Hole with GMRT
ID:
ivo://CDS.VizieR/J/MNRAS/387/1037
Title:
610-MHz survey of Lockman Hole with GMRT
Short Name:
J/MNRAS/387/1037
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present observations of the Lockman Hole with the Giant Metrewave Radio Telescope (GMRT). Twelve pointings were observed, covering a total area of ~5deg^2^ with a resolution of 6x5arcsec^2^, position angle +45deg. The majority of the pointings have an rms noise of ~60uJy/beam before correction for the attenuation of the GMRT primary beam. Techniques used for data reduction and production of a mosaicked image of the region are described, and the final mosaic is presented, along with a catalogue of 2845 sources detected above 6{sigma}. Radio source counts are calculated at 610-MHz and combined with existing 1.4-GHz source counts, in order to show that pure luminosity evolution of the local radio luminosity functions for active galactic nuclei and starburst galaxies is sufficient to account for the two source counts simultaneously.
1122. 610-MHz survey of Lockman Hole with GMRT. II.
ID:
ivo://CDS.VizieR/J/other/BASI/38.103
Title:
610-MHz survey of Lockman Hole with GMRT. II.
Short Name:
J/other/BASI/38.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present further observations of the Lockman Hole field, made with the Giant Metrewave Radio Telescope at 610MHz with a resolution of 6x5arcsec^2^. These complement our earlier observations of the central ~5deg^2^ by covering a further ~8deg^2^, with an r.m.s. noise down to ~80uJy/beam. A catalogue of 4934 radio sources is presented
1123. 74MHz VLA Low-frequency Sky Survey Redux (VLSSr)
ID:
ivo://CDS.VizieR/VIII/97
Title:
74MHz VLA Low-frequency Sky Survey Redux (VLSSr)
Short Name:
VIII/97
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a recent re-reduction of the data from the Very Large Array (VLA) Low-frequency Sky Survey (VLSS). We used the VLSS catalogue as a sky model to correct the ionospheric distortions in the data and create a new set of sky maps and corresponding catalogue at 73.8MHz. The VLSS Redux (VLSSr) has a resolution of 75", and an average map rms noise level of {sigma}~0.1Jy/beam. The clean bias is 0.66x{sigma} and the theoretical largest angular size is 36'. Six previously unimaged fields are included in the VLSSr, which has an unbroken sky coverage over 9.3sr above an irregular southern boundary. The final catalogue includes 92964 sources. The VLSSr improves upon the original VLSS in a number of areas including imaging of large sources, image sensitivity, and clean bias; however the most critical improvement is the replacement of an inaccurate primary beam correction which caused source flux errors which vary as a function of radius to nearest pointing centre in the VLSS.
1124. Michigan Catalogue of HD stars, Vol.5
ID:
ivo://CDS.VizieR/III/214
Title:
Michigan Catalogue of HD stars, Vol.5
Short Name:
III/214
Date:
21 Oct 2021
Publisher:
CDS
Description:
This volume of the catalog contains all HD stars in the declination range -12 degrees up to and including +05 degrees (equinox 1900) and is part of a series of catalogs in the University of Michigan program of systematic reclassification in the MK system of the entire "Henry Draper Catalogue" (HD). The stars were classified visually on objective-prism plates taken with the Michigan Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory. The 4{deg} + 6{deg} prisms yield a dispersion at H_{gamma}_ of 108 {AA}/mm, and the average resolution is about 2 {AA}/mm, comparable to that of the original MK system [MKK]. The spectra were taken on IIaO plates and widened to 0.8 mm, with 20min, 4min, and 1min exposures being obtained. In order to maintain a uniform, consistent system, all the spectral classification was done by one person (Houk). It is recommended that users read the accompanying text (preface.tex) before utilizing the catalogue in order to take full advantage of its contents and to learn the notation and practices followed.
1125. Microlensing events toward the Bulge from MOA-II
ID:
ivo://CDS.VizieR/J/ApJ/778/150
Title:
Microlensing events toward the Bulge from MOA-II
Short Name:
J/ApJ/778/150
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present measurements of the microlensing optical depth and event rate toward the Galactic Bulge (GB) based on two years of the MOA-II survey. This sample contains ~1000 microlensing events, with an Einstein radius crossing time of t_E_<=200 days in 22 bulge fields covering ~42deg^2^ between -5{deg}<l<10{deg} and -7{deg}<b<-1{deg}. Our event rate and optical depth analysis uses 474 events with well-defined microlensing parameters. In the central fields with |l|<5{deg}, we find an event rate of {Gamma}=[2.39+/-1.1]e^[0.60+/-0.05](3-|b|)^x10^-5^/star/yr and an optical depth (for events with t_E_<=200days) of {tau}_200_=[2.35+/-0.18]e^[0.51+/-0.07](3-|b|)^x10^-6^ for the 427 events, using all sources brighter than I_s_<=20mag. The distribution of observed fields is centered at (l,b)=(0.{deg}38, -3.{deg}72). We find that the event rate is maximized at low latitudes and a longitude of l{approx}1{deg}. For the 111 events in 3.2deg^2^ of the central GB at |b|<=3.{deg}0 and 0.{deg}0<=l<=2.{deg}0, centered at (l,b)=(0.{deg}97, -2.{deg}26), we find {Gamma}=4.57_-0.46_^+0.51^x10^-5^/star/yr and {tau}_200_=3.64_-0.45_^+0.51^x10^-6^. We also consider a red clump giant (RCG) star sample with I_s_<17.5, and we find that the event rate for the RCG sample is slightly lower than but consistent with the all-source event rate. The main difference is the lack of long duration events in the RCG sample due to a known selection effect. Our results are consistent with previous optical depth measurements, but they are somewhat lower than previous all-source measurements, and slightly higher than previous RCG optical depth measurements. This suggests that the previously observed difference in optical depth measurements between all-source and RCG samples may largely be due to statistical fluctuations. These event rate measurements toward the central GB are necessary to predict the microlensing event rate and to optimize the survey fields in future space missions such as Wide Field Infrared Space Telescope.
1126. Microlensing optical depth & event rates from MOA-II
ID:
ivo://CDS.VizieR/J/ApJ/827/139
Title:
Microlensing optical depth & event rates from MOA-II
Short Name:
J/ApJ/827/139
Date:
21 Oct 2021
Publisher:
CDS
Description:
We find that significant incompleteness in stellar number counts results in a significant overestimate of the microlensing optical depth {tau} and event rate per star per year {Gamma} toward the Galactic bulge from the first two years of the MOA-II survey. We find that the completeness in red clump giant (RCG) counts f_RC_ decreases proportional to the galactic latitude b, as f_RC_=(0.63+/-0.11)-(0.052+/-0.028)xb, ranging between 1 and 0.7 at b=-6{deg}~-1.5{deg}. The previous measurements using all sources by difference image analysis (DIA) by MACHO and MOA-I suffer the same bias. On the other hand, the measurements using an RCG sample by OGLE-II, MACHO, and EROS were free from this bias because they selected only the events associated with the resolved stars. Thus, the incompleteness both in the number of events and stellar number count cancel out. We estimate {tau} and {Gamma} by correcting this incompleteness. In the central fields with |l|<5{deg}, we find {Gamma}=[18.74+/-0.91]x10^-6^exp[(0.53+/-0.05)(3-|b|)]/star/yr and {tau}_200_=[1.84+/-0.14]x10^-6^exp[(0.44+/-0.07)(3-|b|)] for the 427 events with t_E_<=200 days using all sources brighter than I_s_<=20mag. Our revised all-source {tau} measurements are about 2{sigma} smaller than the other all-source measurements and are consistent with the RCG measurements within 1{sigma}. We conclude that the long-standing problem on discrepancy between the high {tau} with all-source samples by DIA and low {tau} with RCG samples can probably be explained by the incompleteness of the stellar number count. A model fit to these measurements predicts {Gamma}=4.60+/-0.25x10^-5^/star/yr at |b|~-1.4{deg} and -2.25{deg}<l<3.75{deg} for sources with I<=20, where the future space mission, Wide Field Infrared Space Telescope, will observe.
1127. 100-Micron Survey of the Galactic Plane
ID:
ivo://CDS.VizieR/II/56
Title:
100-Micron Survey of the Galactic Plane
Short Name:
II/56
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog represents a survey of a portion of the galactic plane at a wavelength of 100 micrometers with a balloon-borne, stabilized, 12-inch infrared telescope having a sensitivity of 10(-22) W/m2/Hz. The survey covers 750 square degrees of the sky, including most of the galactic plane between galactic longitudes of 335 and 88 degrees, plus a number of other selected areas of interest. Seventy-two sources have been detected, 60 of which are identified with continuum radio sources, bright nebulae, dark nebulae, and infrared stars. The catalog includes right ascension and declination (B1950.0), galactic coordinates, 100-micrometer peak flux densities, sizes of sources, and identifications.
1128. Mid-IR colors of AGNs in the MUSYC ECDF-S
ID:
ivo://CDS.VizieR/J/ApJ/680/130
Title:
Mid-IR colors of AGNs in the MUSYC ECDF-S
Short Name:
J/ApJ/680/130
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the mid-infrared colors of X-ray-detected AGNs and explore mid-infrared selection criteria. Using a statistical matching technique, the likelihood ratio, over 900 IRAC counterparts were identified with a new MUSYC X-ray source catalog that includes ~1000 published X-ray sources in the Chandra Deep Field-South and Extended Chandra Deep Field-South. Most X-ray-selected AGNs have IRAC spectral shapes consistent with power-law slopes, f_{nu}_{prop.to}{nu}^{alpha}^, and display a wide range of colors, -2<=alpha}<=2 Although X-ray sources typically fit to redder (more negative {alpha}) power laws than non-X-ray-detected galaxies, more than 50% do have flat or blue (galaxy-like) spectral shapes in the observed 3-8um band. Only a quarter of the X-ray-selected AGNs detected at 24um are well fit by featureless red power laws in the observed 3.6-24um, likely the subset of our sample whose infrared spectra are dominated by emission from the central AGN region. Most IRAC color selection criteria fail to identify the majority of X-ray-selected AGNs, finding only the more luminous AGNs, the majority of which have broad emission lines. In deep surveys, these color selection criteria select 10%-20% of the entire galaxy population and miss many moderate-luminosity AGNs.
1129. Mid-IR sources in EGS
ID:
ivo://CDS.VizieR/J/ApJS/177/431
Title:
Mid-IR sources in EGS
Short Name:
J/ApJS/177/431
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Extended Groth Strip (EGS) is one of the premier fields for extragalactic deep surveys. Deep observations of the EGS with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope cover an area of 0.38deg^2^ to a 50% completeness limit of 1.5uJy at 3.6um. The catalog comprises 57434 objects detected at 3.6um, with 84%, 28%, and 24% also detected at 4.5, 5.8, and 8.0um, respectively. Number counts are consistent with results from other Spitzer surveys. Color distributions show that the EGS IRAC sources comprise a mixture of populations: low-redshift star-forming galaxies, quiescent galaxies dominated by stellar emission at a range of redshifts, and high-redshift galaxies and AGNs.
1130. Mid-IR variability from the SDWFS
ID:
ivo://CDS.VizieR/J/ApJ/716/530
Title:
Mid-IR variability from the SDWFS
Short Name:
J/ApJ/716/530
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use the multi-epoch, mid-infrared Spitzer Deep Wide-Field Survey (SDWFS; Ashby et al. 2009, Cat. J/ApJ/701/428) to investigate the variability of objects in 8.1deg^2^ of the NOAO Deep Wide Field Survey Bootes field (NDWFS; Jannuzi & Dey 1999ASPC..191..111J). We perform a Difference Image Analysis of the four available epochs between 2004 and 2008, focusing on the deeper 3.6 and 4.5um bands. Out of 474, 179 analyzed sources, 1.1% meet our standard variability selection criteria that the two light curves are strongly correlated (r>0.8) and that their joint variance ({sigma}_12_) exceeds that for all sources with the same magnitude by 2{sigma}. We then examine the mid-IR colors of the variable sources and match them with X-ray sources from the XBootes survey (Murray et al. 2005ApJS..161....1M), radio catalogs (FIRST (Becker et al., Cat. VIII/71) and WSRT (de Vries et al. 2002, Cat. J/AJ/123/1784)), 24um selected active galactic nucleus (AGN) candidates (see Houck et al. 2005ApJ...622L.105H), and spectroscopically identified AGNs from the AGN and Galaxy Evolution Survey (AGES; C. S. Kochanek et al. 2010, in prep). Based on their mid-IR colors, most of the variable sources are AGNs (76%), with smaller contributions from stars (11%), galaxies (6%), and unclassified objects, although most of the stellar, galaxy, and unclassified sources are false positives. For our standard selection criteria, 11%-12% of the mid-IR counterparts to X-ray sources, 24um AGN candidates, and spectroscopically identified AGNs show variability.