中文
相关论文

相关论文: Foregrounds and experiments below 33GHz

200 篇论文

Fluctuations in the redshifted 21 centimeter emission from neutral hydrogen probe the epoch of reionization. We examine the observability of this signal and the impact of extragalactic foreground radio sources. We use cosmological…

天体物理学 · 物理学 2009-11-10 Tiziana Di Matteo , Benedetta Ciardi , Francesco Miniati

Recently correlation analyses between Galactic dust emission templates and a number of CMB data sets have led to differing claims on the origin of the Galactic contamination at low frequencies. de Oliviera-Costa {\em et al} (1999) have…

天体物理学 · 物理学 2009-10-31 P. Mukherjee , A. W. Jones , R. Kneissl , A. N. Lasenby

Measurements of the diffuse extragalactic gamma-ray background (EGRB) are complicated by a strong Galactic foreground. Estimates of the EGRB flux and spectrum, obtained by modeling the Galactic emission, have produced a variety of…

天体物理学 · 物理学 2009-11-10 Uri Keshet , Eli Waxman , Abraham Loeb

The measurement of the Compton edge of the scattered electrons in GRAAL facility in European Synchrotron Radiation Facility (ESRF) in Grenoble with respect to the Cosmic Microwave Background dipole reveals up to 10 sigma variations larger…

The supporting instrument on board the Fermi Gamma-ray Space Telescope, the Gamma-ray Burst Monitor (GBM) is a wide-field gamma-ray monitor composed of 14 individual scintillation detectors, with a field of view which encompasses the entire…

天体物理仪器与方法 · 物理学 2015-06-11 Gerard Fitzpatrick , Sheila McBreen , Valerie Connaughton , Michael Briggs , the GBM Team

We report the spectral index of diffuse radio emission between 50 and 100 MHz from data collected with two implementations of the Experiment to Detect the Global EoR Signature (EDGES) low-band system. EDGES employs a wide beam…

天体物理仪器与方法 · 物理学 2019-01-08 Thomas J. Mozdzen , Nivedita Mahesh , Raul A. Monsalve , Alan E. E. Rogers , Judd D. Bowman

The ability to subtract foreground contamination from low-frequency observations is crucial to reveal the underlying 21 cm signal. The traditional line-of-sight methods can deal with the removal of diffuse emission and unresolved point…

宇宙学与河外天体物理 · 物理学 2015-05-30 Xiao-Chun Mao

We report absolutely calibrated measurements of diffuse radio emission between 90 and 190 MHz from the Experiment to Detect the Global EoR Signature (EDGES). EDGES employs a wide beam zenith-pointing dipole antenna centred on a declination…

天体物理仪器与方法 · 物理学 2016-10-25 Thomas. J. Mozdzen , Judd. D. Bowman , Raul. A. Monsalve , Alan. E. E. Rogers

A proposed method for dealing with foreground emission in upcoming 21-cm observations from the epoch of reionization is to limit observations to an uncontaminated window in Fourier space. Foreground emission can be avoided in this way,…

宇宙学与河外天体物理 · 物理学 2015-12-23 Hannes Jensen , Suman Majumdar , Garrelt Mellema , Adam Lidz , Ilian T. Iliev , Keri L. Dixon

We present the first observation of the diffuse polarized synchrotron radiation of a patch ($\sim 3^\circ \times 3^\circ$) in the BOOMERanG field, one of the areas with the lowest CMB foreground emission. The work has been carried out with…

天体物理学 · 物理学 2009-11-10 G. Bernardi , E. Carretti , S. Cortiglioni , R. J. Sault , M. J. Kesteven , S. Poppi

Due to the scarcity of spectrum resources, the emergence of new technologies and ever-increasing number of wireless devices operating in the radio frequency spectrum lead to data congestion and interference. In this work, we study the…

信号处理 · 电气工程与系统科学 2023-01-09 Amir Hossein Fahim Raouf , Sung Joon Maeng , Ismail Guvenc , Ozgur Ozdemir , Mihail Sichitiu

Stochastic backgrounds of relic gravitons of cosmological origin extend from frequencies of the order of the aHz up to the GHz range. Since the temperature and polarization anisotropies constrain the low frequency normalization of the…

宇宙学与河外天体物理 · 物理学 2016-06-29 Massimo Giovannini

(Abridged) We present the analysis of the first 18 months of data obtained with the COSMOSOMAS experiment at the Teide Observatory (Tenerife). Three maps have been obtained at 12.7, 14.7 and 16.3 GHz covering 9000 square degrees each with a…

We study the spectral and morphological characteristics of the diffuse Galactic emission in the WMAP temperature data using a template-based multi-linear regression, and obtain the following results. 1. We confirm previous observations of a…

天体物理学 · 物理学 2009-06-23 Gregory Dobler , Douglas P. Finkbeiner

The response of the antenna is a source of uncertainty in measurements with the Experiment to Detect the Global EoR Signature (EDGES). We aim to validate the beam model of the low-band (50-100 MHz) dipole antenna with comparisons between…

天体物理仪器与方法 · 物理学 2021-07-07 Nivedita Mahesh , Judd D. Bowman , Thomas J. Mozdzen , Alan E. E. Rogers , Raul A. Monsalve , Steven G. Murray , David Lewis

High-frequency waves (5 mHz to 20mHz) have previously been suggested as a source of energy accounting partial heating of the quiet solar atmosphere. The dynamics of previously detected high-frequency waves is analysed here. Image sequences…

天体物理学 · 物理学 2009-11-13 Aleksandra Andić

In this first paper of the series, we present initial results of newly upgraded Giant Meterwave Radio Telescope (uGMRT) observation of European Large-Area ISO Survey-North 1 (ELAIS-N1) at 325 MHz with 32 MHz bandwidth. Precise measurement…

It has recently become apparent that the background level of diffuse radio emission on the sky is significantly higher than the level that can result from known extragalactic radio source classes or our Galaxy given our current…

宇宙学与河外天体物理 · 物理学 2019-12-02 J. Singal