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相关论文: Blind and non-blind source detection in WMAP 5-yea…

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We present a 3-dimensional matched filtering approach for the blind search of faint emission-line sources in integral-field spectroscopic datasets. The filter is designed to account for the spectrally rapidly varying background noise due to…

天体物理仪器与方法 · 物理学 2023-03-21 Edmund Christian Herenz

A non-Gaussian detection in the WMAP 1-year data is reported. The detection has been found in the combined Q-V-W map proposed by the WMAP team (Komatsu et al. 2003) after applying a wavelet technique based on the Spherical Mexican Hat…

天体物理学 · 物理学 2008-11-26 P. Vielva , E. Martinez-Gonzalez , R. B. Barreiro , J. L. Sanz , L. Cayon

In this work we address the problem of simultaneous multi-frequency detection of extragalactic point sources in maps of the Cosmic Microwave Background. We apply a new linear filtering technique, the so called `matched matrix filters', that…

天体物理学 · 物理学 2009-11-13 D. Herranz , M. Lopez-Caniego , J. L. Sanz , J. Gonzalez-Nuevo

We present some first results on the variability, polarization and general properties of radio sources selected in a blind survey at 20 GHz, the highest frequency at which a sensitive radio survey has been carried out over a large area of…

We present the full source catalogue from the Australia Telescope 20 GHz (AT20G) Survey. The AT20G is a blind radio survey carried out at 20 GHz with the Australia Telescope Compact Array (ATCA) from 2004 to 2008, and covers the whole sky…

Procedures based on current methods to detect sources in X-ray images are applied to simulated XMM images. All significant instrumental effects are taken into account, and two kinds of sources are considered -- unresolved sources…

天体物理学 · 物理学 2009-11-06 I. Valtchanov , M. Pierre , R. Gastaud

We use the Wilkinson Microwave Anisotropy Probe 7-year data (WMAP7) to further probe point source detection technique in the sky maps of the cosmic microwave background (CMB) radiation. The method by Tegmark et al. for foreground reduced…

宇宙学与河外天体物理 · 物理学 2013-07-30 H. G. Khachatryan , G. Nurbaeva , D. Pfenniger , G. Meylan

The first-year WMAP data, in combination with any one of a number of other cosmic probes, show that we live in a flat \Lambda-dominated CDM universe with \Omega_m ~ 0.27 and \Omega_\Lambda ~ 0.73. In this model the late-time action of the…

We repeat the directional spherical real Morlet wavelet analysis, used to detect non-Gaussianity in the Wilkinson Microwave Anisotropy Probe (WMAP) 1-year and 3-year data (McEwen et al. 2005, 2006a), on the WMAP 5-year data. The…

天体物理学 · 物理学 2008-09-02 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

We present a method of reliably extracting the flux of individual sources from sky maps in the presence of noise and a source population in which number counts are a steeply falling function of flux. The method is an extension of a standard…

宇宙学与河外天体物理 · 物理学 2015-03-13 T. M. Crawford , E. R. Switzer , W. L. Holzapfel , C. L. Reichardt , D. P. Marrone , J. D. Vieira

Point Source (PS) detection is an important issue for future Cosmic Microwave Background (CMB) experiments since they are one of the main contaminants to the recovery of CMB signal at small scales. Improving its multifrequency detection…

We present the results of the flux density measurements at 4.85 GHz and 10.45 GHz of a sample of 5998 NVSS radio sources with the Effelsberg 100 m telescope. The initial motivation was the need to identify the NVSS radio sources that could…

宇宙学与河外天体物理 · 物理学 2015-05-13 E. Angelakis , A. Kraus , A. C. S. Readhead , J. A. Zensus , R. Bustos , T. P. Krichbaum , A. Witzel , T. J. Pearson

The Wilkinson Microwave Anisotropy Probe (WMAP) science team has released results from the first year of operation at the Earth-Sun L2 Lagrange point. The maps are consistent with previous observations but have much better sensitivity and…

天体物理学 · 物理学 2007-05-23 E. L. Wright

We stack WMAP 7-year temperature data around extragalactic point sources, showing that the profiles are consistent with WMAP's beam models, in disagreement with the findings of Sawangwit & Shanks (2010). These results require that the…

宇宙学与河外天体物理 · 物理学 2015-06-03 Kasey W. Schultz , Kevin M. Huffenberger

We present a new estimate of foreground emission in the WMAP data, using a Markov chain Monte Carlo (MCMC) method. The new technique delivers maps of each foreground component for a variety of foreground models, error estimates of the…

AIMS. Several authors have claimed to detect a significant cross-correlation between microwave WMAP anisotropies and the SDSS galaxy distribution. We repeat these analyses to determine the different cross-correlation uncertainties caused by…

宇宙学与河外天体物理 · 物理学 2015-05-18 M. Lopez-Corredoira , F. Sylos Labini , J. Betancort-Rijo

We present a statistical method based on a maximum likelihood approach to constrain the number counts of extragalactic sources below the nominal flux-density limit of continuum imaging surveys. We extract flux densities from a radio map…

天体物理仪器与方法 · 物理学 2015-06-16 Ketron Mitchell-Wynne , Mario G. Santos , Jose Afonso , Matt J. Jarvis

We analyse a 154 MHz image made from a 12 h observation with the Murchison Widefield Array (MWA) to determine the noise contribution and behaviour of the source counts down to 30 mJy. The MWA image has a bandwidth of 30.72 MHz, a…

We present new constraints on the non-linear coupling parameter fnl with the Wilkinson Microwave Anisotropy Probe (WMAP) data. We use an updated method based on the spherical Mexican hat wavelet (SMHW) which provides improved constraints on…

宇宙学与河外天体物理 · 物理学 2009-11-13 A. Curto , E. Martinez-Gonzalez , R. B. Barreiro

Applying basic physical principles to recent observational results, we derive upper and lower limits on microwave anisotropy from point sources over the range of frequencies 10-1000 GHz. We examine the level of noise in the observations as…

天体物理学 · 物理学 2007-05-23 Eric Gawiser , Andrew Jaffe , Joseph Silk