中文
相关论文

相关论文: An improved source-subtracted and destriped 408 MH…

200 篇论文

Recent analyses of the WMAP data seem to indicate the possible presence of large-angle anisotropy in the Universe. If confirmed, these can have important consequences for our understanding of the Universe. A number of attempts have recently…

天体物理学 · 物理学 2009-06-23 A. Bernui , B. Mota , M. J. Reboucas , R. Tavakol

One of the main obstacles for extracting the Cosmic Microwave Background (CMB) from mm/submm observations is the pollution from the main Galactic components: synchrotron, free-free and thermal dust emission. The feasibility of using simple…

宇宙学与河外天体物理 · 物理学 2016-07-20 H. U. Nørgaard-Nielsen

WMAP data when combined with ancillary data on free-free, synchrotron and dust allow an improved understanding of the spectrum of emission from each of these components. Here we examine the sky variation at intermediate and high latitudes…

宇宙学与河外天体物理 · 物理学 2013-09-27 Tuhin Ghosh , A. J. Banday , Tess Jaffe , Clive Dickinson , Rod Davies , Richard Davis , Krzysztof Gorski

The WMAP satellite has completed 3 years of observations of the cosmic microwave background radiation. The 3-year data products include several sets of full sky maps of the Stokes I, Q and U parameters in 5 frequency bands, spanning 23 to…

An improved method for subtracting contaminants from Cosmic Microwave Background (CMB) sky maps is presented, and used to estimate how well future experiments will be able to recover the primordial CMB fluctuations. We find that the naive…

天体物理学 · 物理学 2015-06-24 Max Tegmark , George Efstathiou

We extend the internal template foreground removal method by accounting for spatially varying spectral parameters such as the spectral indices of synchrotron and dust emission and the dust temperature. As the previous algorithm had to…

宇宙学与河外天体物理 · 物理学 2019-02-04 Kiyotomo Ichiki , Hiroaki Kanai , Nobuhiko Katayama , Eiichiro Komatsu

In the 1998-99 flight, BOOMERanG has produced maps of $\sim 4 %$ of the sky at high Galactic latitudes, at frequencies of 90, 150, 240 and 410 GHz, with resolution $\simgt 10'$. The faint structure of the Cosmic Microwave Background at…

Understanding diffuse Galactic radio emission is interesting both in its own right and for minimizing foreground contamination of cosmological measurements. Cosmic Microwave Background experiments have focused on frequencies > 10 GHz,…

It is commonplace in pulsar and fast radio burst (FRB) literature to estimate sky temperature by frequency-scaling of the Haslam et al. (1982) 408 MHz map. I suggest that this practice should stop, in favor of using readily-available global…

高能天体物理现象 · 物理学 2021-11-03 Danny C. Price

The search for emission from weakly interacting massive particle (WIMP) dark matter annihilation and decay has become a multi-pronged area of research not only targeting a diverse selection of astrophysical objects, but also taking…

We present the first model of full-sky polarized synchrotron emission that is derived from all WMAP and Planck LFI frequency maps. The basis of this analysis is the set of end-to-end reprocessed Cosmoglobe Data Release 1 sky maps presented…

Broadband time-ordered data obtained from telescopes with a wavelength-dependent, asymmetric beam pattern can be used to extract maps at multiple wavelengths from a single scan. This technique is especially useful when collecting data on…

天体物理仪器与方法 · 物理学 2023-06-06 Brianna Cantrall , Solomon Quinn , Emory F. Bunn

As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…

The Australian SKA Pathfinder (ASKAP) radio telescope has carried out a survey of the entire Southern Sky at 887.5MHz. The wide area, high angular resolution, and broad bandwidth provided by the low-band Rapid ASKAP Continuum Survey…

By accumulating data from the Solid-state Slit Camera (SSC) on board the MAXI mission for 2 years from 2009 to 2011, diffuse X-ray background maps were obtained in energies of 0.7--1.0, 1.0--2.0, and 2.0--4.0 keV. They are the first ones…

高能天体物理现象 · 物理学 2020-02-12 Satoshi Nakahira , Hiroshi Tsunemi , Hiroshi Tomida , Shinya Nakashima , Ryuho Kataoka , Kazuo Makishima

We extend the analysis of the MAXIMA-1 cosmic microwave background (CMB) data to smaller angular scales. MAXIMA, a bolometric balloon experiment, mapped a 124 deg$^2$ region of the sky with 10\arcmin resolution at frequencies of 150, 240…

Foreground removal is one of the biggest challenges in the detection of the Cosmic Dawn (CD) and Epoch of Reionization (EoR). Various foreground subtraction techniques have been developed based on the spectral smoothness of foregrounds.…

宇宙学与河外天体物理 · 物理学 2024-02-01 Mengfan He , Qian Zheng , Quan Guo , Huanyuan Shan , Zhenghao Zhu , Yushan Xie , Yan Huang , Feiyu Zhao

Neutral hydrogen intensity mapping can in principle deliver rapid and large-volume cosmological surveys with exquisitely accurate redshifts that are determined directly from imaging. However, intensity maps suffer from very strong…

宇宙学与河外天体物理 · 物理学 2024-05-30 Rahul Kothari , Roy Maartens

Measurements of the Galactic synchrotron emission is relevant for the 21-cm studies from the Epoch of Reionization. The study of the synchrotron emission is also useful to quantify the fluctuations in the magnetic field and the cosmic ray…

宇宙学与河外天体物理 · 物理学 2021-01-13 Samir Choudhuri , Abhik Ghosh , Nirupam Roy , Somnath Bharadwaj , Huib. T. Intema , Sk. Saiyad Ali

One of the major priorities of international radio astronomy is to study the early universe through the detection of the 21 cm HI line from the epoch of reionisation (EoR). Due to the weak nature of the 21 cm signal, an important part in…

天体物理仪器与方法 · 物理学 2022-04-27 Michael A. Kriele , Randall B. Wayth , Mark J. Bentum , Budi Juswardy , Cathryn M. Trott