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24111. WMAP cosmic microwave background data
ID:
ivo://CDS.VizieR/J/A+A/557/L1
Title:
WMAP cosmic microwave background data
Short Name:
J/A+A/557/L1
Date:
21 Oct 2021
Publisher:
CDS
Description:
There is currently a debate over the existence of claimed statistical anomalies in the cosmic microwave background (CMB), recently confirmed in Planck data. Recent work has focussed on methods for measuring statistical significance, on masks and on secondary anisotropies as potential causes of the anomalies. We investigate simultaneously the method for accounting for masked regions and the foreground integrated Sachs-Wolfe (ISW) signal. We search for trends in different years of WMAP CMB data with different mask treatments. We reconstruct the ISW field due to the 2 Micron All-Sky Survey (2MASS) and the NRAO VLA Sky Survey (NVSS) up to l=5, and we focus on the Axis of Evil (AoE) statistic and even/odd mirror parity, both of which search for preferred axes in the Universe. We find that removing the ISW reduces the significance of these anomalies in WMAP data, though this does not exclude the possibility of exotic physics. In the spirit of reproducible research, all reconstructed maps and codes will be made available for download at http://www.cosmostat.org/anomaliesCMB.html .
24112. 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.
24113. 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:
14 Feb 2025
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 & 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 & 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 > 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 > 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 "deboosting"). 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&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 <a href="/W3Browse/wmap/wmapptsrc.html">WMAPPTSRC</a> 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&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 <a href="http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_cmb_free_9yr_v5.txt">http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_cmb_free_9yr_v5.txt</a>. The source_flag values of 'M' in this file were changed to the 'a' values that were used in the printed version of this table. This is a service provided by NASA HEASARC .
24114. 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:
14 Feb 2025
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<sub>l</sub>/[(b<sub>l</sub>)<sup>2</sup> C<sub>l</sub>(cmb) + C<sub>l</sub>(noise)], where b<sub>l</sub> is the transfer function of the WMAP beam response, C<sub>l</sub>(cmb) is the CMB angular power spectrum, and C<sub>l</sub>(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 > 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&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 <a href="/W3Browse/wmap/wmapcmbfps.html">WMAPCMBFPS</a> 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&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 <a href="http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_9yr_v5.txt">http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_9yr_v5.txt</a>. 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 .
24115. WMAP Nine Year Galaxy Removed
ID:
ivo://nasa.heasarc/skyview/wmap
Title:
WMAP Nine Year Galaxy Removed
Short Name:
WMAP
Date:
14 Feb 2025
Publisher:
NASA/GSFC HEASARC
Description:
These survey represents a combination of the 9-year data combined in a way that is intended to minimize the contribution from the galaxy. The data measure the temperature deviation from a uniform black body. <p> The original data are available at the <https://lambda.gsfc.nasa.gov>LAMBDA archive</a>. <p> The original data are stored in HEALPix pixels. SkyView treats HEALPix as a standard projection but assumes that the HEALPix data is in a projection plane with a rotation of -45 degrees. The rotation transforms the HEALPix pixels from diamonds to squares so that the boundaries of the pixels are treated properly. The special HealPixImage class is used so that SkyView can use the HEALPix FITS files directly. The HealPixImage simulates a rectangular image but translates the pixels from that image to the nested HEALPix structure that is used by the WMAP data. </p> Provenance: WMAP Mission/LAMBDA archive. This is a service of NASA HEASARC.
24116. 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^.
24117. 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.
24118. 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:
14 Feb 2025
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 .
24119. WMAP 3 Year Temperature Analysis
ID:
ivo://CDS.VizieR/J/ApJS/170/288
Title:
WMAP 3 Year Temperature Analysis
Short Name:
J/ApJS/170/288
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new full-sky temperature maps in five frequency bands from 23 to 94GHz, based on data from the first 3 years of the WMAP sky survey. The new maps are consistent with the first-year maps and are more sensitive. We employ two forms of multifrequency analysis to separate astrophysical foreground signals from the CMB, each of which improves on our first-year analyses. First, we form an improved "Internal Linear Combination" (ILC) map, based solely on WMAP data, by adding a bias-correction step and by quantifying residual uncertainties in the resulting map. Second, we fit and subtract new spatial templates that trace Galactic emission; in particular, we now use low-frequency WMAP data to trace synchrotron emission instead of the 408MHz sky survey. The WMAP point source catalog is updated to include 115 new sources whose detection is made possible by the improved sky map sensitivity. We derive the angular power spectrum of the temperature anisotropy using a hybrid approach that combines a maximum likelihood estimate at low l (large angular scales) with a quadratic cross-power estimate for l>30. The resulting multifrequency spectra are analyzed for residual point source contamination. At 94GHz the unmasked sources contribute 128+/-27^{micron}^K^2^ to l(l+1)C_l_/2{pi} at l=1000. After subtracting this contribution, our best estimate of the CMB power spectrum is derived by averaging cross-power spectra from 153 statistically independent channel pairs. A simple six-parameter {LAMBDA}CDM model continues to fit CMB data and other measures of large-scale structure remarkably well. The new polarization data produce a better measurement of the optical depth to reionization, {tau}=0.089+/-0.03. This new and tighter constraint on {tau} help break a degeneracy with the scalar spectral index, which is now found to be ns=0.960+/-0.016.
24120. WMAP 3-yr sources at 16 and 33GHz
ID:
ivo://CDS.VizieR/J/MNRAS/400/984
Title:
WMAP 3-yr sources at 16 and 33GHz
Short Name:
J/MNRAS/400/984
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present follow-up observations of 97 point sources from the Wilkinson Microwave Anisotropy Probe (WMAP) 3-yr data, contained within the New Extragalactic WMAP Point Source catalogue between -4{deg}<=DE<=60{deg}; the sources form a flux-density-limited sample complete to 1.1Jy (~5{sigma}) at 33GHz. Our observations were made at 16GHz using the Arcminute Microkelvin Imager and at 33GHz with the Very Small Array (VSA).

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