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17421. W51 line of sight deuterium fractionation
ID:
ivo://CDS.VizieR/J/A+A/597/A45
Title:
W51 line of sight deuterium fractionation
Short Name:
J/A+A/597/A45
Date:
21 Oct 2021
Publisher:
CDS
Description:
Herschel/HIFI observations toward the compact HII region W51 has revealed the presence of a cold dense core along its line of sight in a high-velocity stream located just in front of W51. This detection has been made possible through absorption measurements of low-energy transitions of HDO, NH_3_, and C_3_ against the bright background emitted by the star-forming region. We present a follow-up study of this core using the high sensitivity and high spectral resolution provided by the IRAM 30m telescope. We report new detections of this core in absorption for DCO^+^ (2-1, 3-2), H^13^CO^+^ (1-0), DNC (3-2), HN^13^C (1-0), p-H_2_CO (2_0,2_-1_0,1_, 3_0,3_-2_0,2_), and in emission for o-NH2D. We also report interferometric observation of this last species using the IRAM/NOEMA telescope, revealing the fragmented nature of the source through the detection of two cores, separated by 0.19-0.24pc, with average sizes of less than 0.16-0.19pc. From a non-LTE analysis, we are able to estimate the density (~2.5x10^4^cm^-3^) and temperature (~10K) of this component, typical of what is found in dark clouds. This component (called W51-core) has the same DCO^+^/HCO^+^ ratio (0.02) as TMC-1 and a high DNC/HNC ratio (0.14). Detection of these deuterated species indicates that W51-core is similar to an early-phase low-mass star-forming region, formed from the interaction between the W51 giant molecular cloud and the high-velocity stream in front of it. The W51 complex being at about 5kpc, these findings lead to what is the first detection of the earliest phase of low-mass star-forming region at such a large distance.
17422. W3 Main JHKs photometry
ID:
ivo://CDS.VizieR/J/A+A/561/A12
Title:
W3 Main JHKs photometry
Short Name:
J/A+A/561/A12
Date:
21 Oct 2021
Publisher:
CDS
Description:
Embedded clusters like W3 Main are complex and dynamically evolving systems that represent an important phase in the star formation process. We aim to characterize of the entire stellar content of W3 Main in a statistical sense, which will then identify possible differences in evolutionary phase of the stellar populations and find clues about the formation mechanism of this massive embedded cluster. Deep JHKs imaging is used to derive the disk fraction, Ks-band luminosity functions, and mass functions for several subregions in W3 Main. A two-dimensional completeness analysis using artificial star experiments is applied as a crucial ingredient for assessing realistic completeness limits for our photometry. We find an overall disk fraction of 7.7+/-2.3%, radially varying from 9.4+/-3.0 in the central 1pc to 5.6+/-2.2% in the outer parts of W3 Main. The mass functions derived for three subregions are consistent with a Kroupa and Chabrier mass function. The mass function of IRSN3 is complete down to 0.14M_{sun}_ and shows a break at M~0.5M_{sun}_. We interpret the higher disk fraction in the center as evidence that the cluster center is younger. We find that the evolutionary sequence observed in the low-mass stellar population is consistent with the observed age spread among the massive stars. An analysis of the mass function variations does not show evidence of mass segregation. W3 Main is currently still actively forming stars, showing that the ionizing feedback of OB stars is confined to small areas (~0.5pc). The FUV feedback might be influencing large regions of the cluster as suggested by the low overall disk fraction.
17423. W51 Main NH_3_ and CH_3_OH data cubes
ID:
ivo://CDS.VizieR/J/A+A/589/A44
Title:
W51 Main NH_3_ and CH_3_OH data cubes
Short Name:
J/A+A/589/A44
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper is the third in a series of NH_3_ multilevel imaging studies in well-known, high-mass star-forming regions. The main goal is to characterize kinematics and physical conditions of (hot and dense) circumstellar molecular gas around O-type young stars. We want to map at subarcsecond resolution highly excited inversion lines of NH_3_ in the high-mass star-forming region W51 Main (distance = 5.4kpc), which is an ideal target to constrain theoretical models of high-mass star formation. Using the Karl Jansky Very Large Array (JVLA), we mapped the hot and dense molecular gas in W51 Main with ~0.2"-0.3" angular resolution in five metastable (J = K) inversion transitions of ammonia (NH_3_): (J,K) = (6, 6), (7, 7), (9, 9), (10, 10), and (13, 13). These lines arise from energy levels between ~400K and ~1700K above the ground state. We also made maps of the (free-free) continuum emission at frequencies between 25 and 36GHz.
17424. WMAP3 catalogue
ID:
ivo://CDS.VizieR/J/A+A/508/107
Title:
WMAP3 catalogue
Short Name:
J/A+A/508/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an extensive search to identify the counterparts of all the microwave foreground sources listed in the WMAP 3-year catalogue using literature and archival data. Our work has led to the identification of 309 WMAP sources, 98% of which are blazars, radio quasars, or radio galaxies. Only 7 WMAP detections were identified with other types of cosmic sources (3 starburst galaxies and 4 planetary/LBN nebulae). At present, 15 objects (<5%) still remain without identification because of the unavailability of optical spectroscopic data or a clear radio counterpart. Our results allow us to define a flux-limited sample of 203 high Galactic latitude microwave sources (f_41GHz_>=1Jy, |b_II_|>15{deg} that is virtually completely identified (99%).
17425. WMAP five-year source catalog
ID:
ivo://CDS.VizieR/J/ApJS/180/283
Title:
WMAP five-year source catalog
Short Name:
J/ApJS/180/283
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the list of point sources found in the Wilkinson Microwave Anisotropy Probe (WMAP) five-year maps. The technique used in the first-year and three-year analyses now finds 390 point sources, and the five-year source catalog is complete for regions of the sky away from the Galactic plane to a 2Jy limit, with SNR>4.7 in all bands in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the cosmic microwave background (CMB) anisotropy is the largest uncertainty. A separate search of CMB-free V-W maps finds 99 sources of which all but one can be identified with known radio sources. The sources seen by WMAP are not strongly polarized. Many of the WMAP sources show significant variability from year to year, with more than a 2:1 range between the minimum and maximum fluxes.
17426. WMAP Nine-Year CMB-Free QVW Point Source Catalog
ID:
ivo://nasa.heasarc/wmapcmbfps
Title:
WMAP Nine-Year CMB-Free QVW Point Source Catalog
Short Name:
WMAPCMBFPS
Date:
01 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The Wilkinson Microwave Anisotropy Probe (WMAP) is designed to produce all-sky maps of the cosmic microwave background (CMB) anisotropy. The WMAP 9-Year CMB-Free Point Source Catalog contained herein has information on 502 point sources in three frequency bands (41, 61 and 94 GHz, also known as the Q, V, and W bands, respectively) based on data from the entire 9 years of the WMAP sky survey from 10 Aug 2001 0:00 UT to 10 Aug 2010 0:00 UT, inclusive. The CMB-free method of point source identification was originally applied to one-year and three-year V- and W-band maps by Chen &amp; Wright (2008, ApJ, 681, 747) and to five-year V- and W-band maps by Wright et al. (2009, ApJS, 180, 283). The method used here is that applied to five-year Q-, V-, and W-band maps by Chen &amp; Wright (2009, ApJ, 694, 222) and to seven-year Q-, V-, and W-band maps by Gold et al. (2011, ApJS, 192, 15). The V- and W-band maps are smoothed to Q-band resolution. An internal linear combination (ILC) map (see Section 5.3.3 of the reference paper) is then formed from the three maps using weights such that CMB fluctuations are removed, flat-spectrum point sources are retained with fluxes normalized to Q-band, and the variance of the ILC map is minimized. The ILC map is filtered to reduce noise and suppress large angular scale structure. Peaks in the filtered map that are &gt; 5 sigma and outside of the nine-year point source catalog mask are identified as point sources, and source positions are obtained by fitting the beam profile plus a baseline to the filtered map for each source. For the nine- year analysis, the position of the brightest pixel is adopted instead of the fit position in rare instances where they differ by &gt; 0.1 degrees. Source fluxes are estimated by integrating the Q, V, and W temperature maps within 1.25 degrees of each source position, with a weighting function to enhance the contrast of the point source relative to background fluctuations, and applying a correction for Eddington bias due to noise (sometimes called &quot;deboosting&quot;). The authors identify possible 5-GHz counterparts to the WMAP sources found by cross-correlating with the GB6 (Gregory et al. 1996, ApJS, 103, 427), PMN (Griffith et al. 1994, ApJS, 90, 179; Griffith et al. 1995, ApJS, 97, 347; Wright et al. 1994, ApJS, 94, 111; Wright et al. 1996, ApJS, 103, 145), Kuehr et al. (1981, A&amp;AS, 45, 367), and Healey et al. (2009, AJ, 138, 1032) catalogs. A 5-GHz source is identified as a counterpart if it lies within 11 arcminutes of the WMAP source position (the mean WMAP source position uncertainty is 4 arcminutes). When two or more 5 GHz sources are within 11 arcminutes, the brightest is assumed to be the counterpart and a multiple identification flag is entered in the catalog. A separate 9-year Point Source Catalog (available in Browse as the &lt;a href="/W3Browse/wmap/wmapptsrc.html"&gt;WMAPPTSRC&lt;/a&gt; table) has information on 501 point sources in five frequency bands from 23 to 94 GHz that were found using an alternative method. The two catalogs have 387 sources in common. As noted by Gold et al. (2011, ApJS, 192, 15), differences in the source populations detected by the two search methods are largely caused by Eddington bias in the five-band source detections due to CMB fluctuations and noise. At low flux levels, the five-band method tends to detect point sources located on positive CMB fluctuations and to overestimate their fluxes, and it tends to miss sources located in negative CMB fluctuations. Other point source detection methods have been applied to WMAP data and have identified sources not found by our methods (e.g., Scodeller et al. (2012, ApJ, 753, 27); Lanz (2012, ADASS 7); Ramos et al. (2011, A&amp;A, 528, A75), and references therein). For more details of how the point source catalogs were constructed, see Section 5.2.2 of the reference paper. This table was last updated by the HEASARC in January 2013 based on an electronic version of Table 19 from the reference paper which was obtained from the LAMBDA web site, the file &lt;a href="http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_cmb_free_9yr_v5.txt"&gt;http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_cmb_free_9yr_v5.txt&lt;/a&gt;. The source_flag values of &#39;M&#39; in this file were changed to the &#39;a&#39; values that were used in the printed version of this table. This is a service provided by NASA HEASARC .
17427. WMAP Nine-Year Five-Band Point Source Catalog
ID:
ivo://nasa.heasarc/wmapptsrc
Title:
WMAP Nine-Year Five-Band Point Source Catalog
Short Name:
WMAPPTSRC
Date:
01 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The Wilkinson Microwave Anisotropy Probe (WMAP) is designed to produce all-sky maps of the cosmic microwave background (CMB) anisotropy. The WMAP 9-Year Point Source Catalog contained herein has information on point sources in five frequency bands from 23 to 94 GHz, based on data from the entire 9 years of the WMAP sky survey from 10 Aug 2001 0:00 UT to 10 Aug 2010 0:00 UT, inclusive. The 5-band search technique used in the first-year, 3-year, 5-year and 7-year analyses now finds 501 point sources, compared to 471 point sources found in the 7-year analysis and 390 sources found in the 5-year analysis. The 5-band search method is largely unchanged from the 7-year analysis (Gold et al. 2011, ApJS, 192, 15). This method searches for point sources in each of the five WMAP wavelength bands. The nine-year signal-to-noise ratio map in each band is filtered in harmonic space by b&lt;sub&gt;l&lt;/sub&gt;/[(b&lt;sub&gt;l&lt;/sub&gt;)&lt;sup&gt;2&lt;/sup&gt; C&lt;sub&gt;l&lt;/sub&gt;(cmb) + C&lt;sub&gt;l&lt;/sub&gt;(noise)], where b&lt;sub&gt;l&lt;/sub&gt; is the transfer function of the WMAP beam response, C&lt;sub&gt;l&lt;/sub&gt;(cmb) is the CMB angular power spectrum, and C&lt;sub&gt;l&lt;/sub&gt;(noise) is the noise power. The filtering suppresses CMB and Galactic foreground fluctuations relative to point sources. For each peak in the filtered maps that is &gt; 5 sigma in any band, the unfiltered temperature map in each band is fit with the sum of a planar base level and a beam template formed by convolving an azimuthally symmetrized beam profile with a skymap pixel. (This method was previously used by Weiland et al. (2011, ApJS, 192, 19) for selected celestial calibration sources and is more accurate than the Gaussian fitting that was used for the seven-year and earlier point source analyses). The peak temperature from each beam template fit is converted to a source flux density using the conversion factor Gamma given in Table 3 of the reference paper. The flux density uncertainty is calculated from the 1-sigma uncertainty in the peak temperature, and does not include any additional uncertainty due to Eddington bias. Flux density values are entered into the catalog for bands where they exceed 2 sigma and where the source width from an initial Gaussian fit is within a factor of two of the beam width. A point source catalog mask is used to exclude sources in the Galactic plane and Magellanic cloud regions. This mask has changed from the seven-year analysis in accordance with changes in the KQ85 temperature analysis mask. A map pixel is outside of the nine-year point source catalog mask if it is either outside of the diffuse component of the nine-year KQ85 temperature analysis mask or outside of the seven-year point source catalog mask. The present mask admits 83% of the sky, compared to 82% and 78% for the previous 7-year and 5-year versions, respectively. The authors identify possible 5-GHz counterparts to the WMAP sources found by cross-correlating with the GB6 (Gregory et al. 1996, ApJS, 103, 427), PMN (Griffith et al. 1994, ApJS, 90, 179; Griffith et al. 1995, ApJS, 97, 347; Wright et al. 1994, ApJS, 94, 111; Wright et al. 1996, ApJS, 103, 145), Kuehr et al. (1981, A&amp;AS, 45, 367), and Healey et al. (2009, AJ, 138, 1032) catalogs. A 5-GHz source is identified as a counterpart if it lies within 11 arcminutes of the WMAP source position (the mean WMAP source position uncertainty is 4 arcminutes). When two or more 5 GHz sources are within 11 arcminutes, the brightest is assumed to be the counterpart and a multiple identification flag is entered in the catalog. A separate 9-year CMB-free Point Source Catalog (available in Browse as the &lt;a href="/W3Browse/wmap/wmapcmbfps.html"&gt;WMAPCMBFPS&lt;/a&gt; table) has information on point sources in three frequency bands from 41 to 94 GHz: the CMB-free method identified 502 point sources in a linear combination map formed from 41, 61 and 94 GHz band maps using weights such that CMB fluctuations are removed and flat-spectrum point sources are retained. The two catalogs have 387 sources in common. As noted by Gold et al. (2011, ApJS, 192, 15), differences in the source populations detected by the two search methods are largely caused by Eddington bias in the five-band source detections due to CMB fluctuations and noise. At low flux levels, the five-band method tends to detect point sources located on positive CMB fluctuations and to overestimate their fluxes, and it tends to miss sources located in negative CMB fluctuations. Other point source detection methods have been applied to WMAP data and have identified sources not found by our methods (e.g., Scodeller et al. (2012, ApJ, 753, 27); Lanz (2012, ADASS 7); Ramos et al. (2011, A&amp;A, 528, A75), and references therein). For more details of how the point source catalogs were constructed, see Section 5.2.2 of the reference paper. This table was last updated by the HEASARC in January 2012 based on an electronic version of Table 18 from the 2012 (ApJS, submitted) paper which was obtained from the LAMBDA web site, the file &lt;a href="http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_9yr_v5.txt"&gt;http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_9yr_v5.txt&lt;/a&gt;. The source_flag values were modified from those given in this file to reflect the values that were given in the printed version of the table. This is a service provided by NASA HEASARC .
17428. WMAP observations of Planck ESZ clusters
ID:
ivo://CDS.VizieR/J/ApJ/771/137
Title:
WMAP observations of Planck ESZ clusters
Short Name:
J/ApJ/771/137
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine the Sunyaev-Zeldovich (SZ) effect in the seven year Wilkinson Microwave Anisotropy Probe (WMAP) data by cross-correlating it with the Planck Early-release Sunyaev-Zeldovich catalog (Cat. VIII/88/esz). Our analysis proceeds in two parts. We first perform a stacking analysis in which the filtered WMAP data are averaged at the locations of the 175 Planck clusters. We then perform a regression analysis to compare the mean amplitude of the SZ signal, Y_500_, in the WMAP data to the corresponding amplitude in the Planck data. The aggregate Planck clusters are detected in the seven year WMAP data with a signal-to-noise ratio of 16.3. In the regression analysis, we find that the SZ amplitude measurements agree to better than 25%: a=1.23+/-0.18 for the fit Y_500_^wmap^=aY_500_^planck^.
17429. WMAP point sources at 61 and 94GHz
ID:
ivo://CDS.VizieR/J/MNRAS/428/3048
Title:
WMAP point sources at 61 and 94GHz
Short Name:
J/MNRAS/428/3048
Date:
21 Oct 2021
Publisher:
CDS
Description:
The detection of point sources in cosmic microwave background maps is usually based on a single-frequency approach, whereby maps at each frequency are filtered separately and the spectral information on the sources is derived combining the results at the different frequencies. In contrast, in the case of multifrequency detection methods, source detection and spectral information are tightly interconnected in order to increase the source detection efficiency. In this work we apply the matched multifiltermethod to the detection of point sources in the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year data at 61 and 94GHz. This linear filtering technique takes into account the spatial and the cross-power spectrum information at the same time using the spectral behaviour of the sources without making any a priori assumption about it.
17430. WMAP 7-Year Internal Templates and Needlets New Source Catalog
ID:
ivo://nasa.heasarc/wmapitnpts
Title:
WMAP 7-Year Internal Templates and Needlets New Source Catalog
Short Name:
WMAPITNPTS
Date:
01 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The authors have developed a new needlet-based method to detect point sources in cosmic microwave background (CMB) maps and have applied it to the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year data. They use both the individual frequency channels as well as internal templates, the latter being the difference between pairs of frequency channels and hence having the advantage that the CMB component is eliminated. Using the area of the sky outside the Kq85 galactic mask, they detect a total of 2102 point sources at the 5-sigma level in either the frequency maps or the internal templates. Of these, 1116 are detected either at 5 sigma directly in the frequency channels or at 5 sigma in the internal templates and &gt;= 3 sigma at the corresponding position in the frequency channels. Of the 1116 sources, 603 are detections that have not been reported so far in WMAP data. The authors have made a catalog of these sources available with position and flux estimated in the WMAP channels where they are seen. In total, they identified 1029 of the 1116 sources with counterparts at 5 GHz and 69 at other frequencies. This table was created by the HEASARC in July 2012 based on an electronic version of Table 6 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .

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