中文
相关论文

相关论文: Source Finding in Linear Polarization for LOFAR, a…

200 篇论文

We present the results of a polarization study based upon relativistic magnetohydrodynamic modelling of jets running into hydrostatic, spherically symmetric cluster atmospheres. For the first time in a numerical simulation, we derive…

高能天体物理现象 · 物理学 2025-08-14 Michael Stimpson , Martin Hardcastle , Martin Krause

Radio frequency sources are observed at a fusion center via sensor measurements made over slow flat-fading channels. The number of sources may be larger than the number of sensors, but their activity is sparse and intermittent with bursty…

信号处理 · 电气工程与系统科学 2019-08-07 Annan Dong , Osvaldo Simeone , Alexander Haimovich , Jason Dabin

The process of determining the number and characteristics of sources in astronomical images is so fundamental to a large range of astronomical problems that it is perhaps surprising that no standard procedure has ever been defined that has…

天体物理仪器与方法 · 物理学 2015-06-03 Minh Huynh , Andrew Hopkins , Ray Norris , Paul Hancock , Tara Murphy , Russell Jurek , Matthew Whiting

Weak gravitational lensing measurements are traditionally made at optical wavelengths where many highly resolved galaxy images are readily available. However, the Square Kilometre Array (SKA) holds great promise for this type of measurement…

宇宙学与河外天体物理 · 物理学 2015-01-19 Prina Patel , Ian Harrison , Sphesihle Makhathini , Filipe Abdalla , David Bacon , Michael L. Brown , Ian Heywood , Matt Jarvis , Oleg Smirnov

We develop a framework for localized source detection in dynamical systems governed by nonlinear partial differential equations based on first and second-order sensitivity analysis. Building on the standard adjoint formulation, which…

流体动力学 · 物理学 2026-05-18 Qi Wang , Zejian You

Numerical simulations offer the unique possibility to forecast the results of surveys and targeted observations that will be performed with next generation instruments like the Square Kilometre Array. In this paper, we investigate for the…

星系天体物理 · 物理学 2019-02-27 F. Loi , M. Murgia , F. Govoni , V. Vacca , I. Prandoni , A. Bonafede , L. Feretti

Low frequency radio waves, while challenging to observe, are a rich source of information about pulsars. The LOw Frequency ARray (LOFAR) is a new radio interferometer operating in the lowest 4 octaves of the ionospheric "radio window":…

Transient radio signals of astrophysical origin present an avenue for studying the dynamic universe. With the next generation of radio interferometers being planned and built, there is great potential for detecting and studying large…

天体物理仪器与方法 · 物理学 2015-05-27 Cathryn M. Trott , Randall B. Wayth , Jean-Pierre R. Macquart , Steven J. Tingay

The detection of polarized sources in the WMAP 5-year data is a very difficult task. The maps are dominated by instrumental noise and only a handful of sources show up as clear peaks in the Q and U maps. Optimal linear filters applied at…

宇宙学与河外天体物理 · 物理学 2014-11-20 M. Lopez-Caniego , M. Massardi , J. Gonzalez-Nuevo , L. Lanz , D. Herranz , G. De Zotti , J. L. Sanz , F. Argueso

Reconstructing sky models from dirty radio images for accurate source localization and flux estimation is crucial for studying galaxy evolution at high redshift, especially in deep fields using instruments like the Atacama Large Millimetre…

Unveiling the intergalactic magnetic field (IGMF) in filaments of galaxies is a very important and challenging subject in modern astronomy. In order to probe the IGMF from rotation measures (RMs) of extragalactic radio sources, we need to…

宇宙学与河外天体物理 · 物理学 2015-06-18 Takuya Akahori , Kohei Kumazaki , Keitaro Takahashi , Dongsu Ryu

By measuring photoelectron tracks, the gas pixel detectors of the Imaging X-ray Polarimetry Explorer satellite provide estimates of the photon detection location and its electric vector position angle (EVPA). However, imperfections in…

天体物理仪器与方法 · 物理学 2024-09-24 Jack T. Dinsmore , Roger W. Romani

In this paper we consider the problem of localizing a set of broadband sources from a finite window of measurements. In the case of narrowband sources this can be reduced to the problem of spectral line estimation, where our goal is simply…

信号处理 · 电气工程与系统科学 2022-10-24 Coleman DeLude , Rakshith Sharma , Santhosh Karnik , Christopher Hood , Mark Davenport , Justin Romberg

We identified a highly-polarized, steep-spectrum radio source in a deep image with the Australian Square Kilometre Array Pathfinder (ASKAP) telescope at 888 MHz. After considering and rejecting a stellar origin for this source, we…

We present a new method to calculate the polarised synchrotron emission of radio AGN sources using magnetic field information from 3-dimensional relativistic magnetohydrodynamical (RMHD) simulations. Like its predecessor, which uses…

高能天体物理现象 · 物理学 2025-09-30 Larissa Jerrim , Stas Shabala , Patrick Yates-Jones , Martin Krause , Ross Turner , Georgia Stewart , Chris Power

We present a catalog of Faraday rotation measures (RMs) and redshifts for 4003 extragalactic radio sources detected at 1.4 GHz, derived by identifying optical counterparts and spectroscopic redshifts for linearly polarized radio sources…

宇宙学与河外天体物理 · 物理学 2020-04-02 Alison M. Hammond , Timothy Robishaw , B. M. Gaensler

This study aims to characterise the polarized foreground emission in the ELAIS-N1 field and to address its possible implications for the extraction of the cosmological 21-cm signal from the Low-Frequency Array - Epoch of Reionization…

星系天体物理 · 物理学 2014-09-05 V. Jelic , A. G. de Bruyn , M. Mevius , F. B. Abdalla , K. M. B. Asad , G. Bernardi , M. A. Brentjens , S. Bus , E. Chapman , B. Ciardi , S. Daiboo , E. R. Fernandez , A. Ghosh , G. Harker , H. Jensen , S. Kazemi , L. V. E. Koopmans , P. Labropoulos , O. Martinez-Rubi , G. Mellema , A. R. Offringa , V. N. Pandey , A. H. Patil , R. M. Thomas , H. K. Vedantham , V. Veligatla , S. Yatawatta , S. Zaroubi , A. Alexov , J. Anderson , I. M. Avruch , R. Beck , M. E. Bell , M. J. Bentum , P. Best , A. Bonafede , J. Bregman , F. Breitling , J. Broderick , W. N. Brouw , M. Bruggen , H. R. Butcher , J. E. Conway , F. de Gasperin , E. de Geus , A. Deller , R. -J. Dettmar , S. Duscha , J. Eisloffel , D. Engels , H. Falcke , R. A. Fallows , R. Fender , C. Ferrari , W. Frieswijk , M. A. Garrett , J. Griessmeier , A. W. Gunst , J. P. Hamaker , T. E. Hassall , M. Haverkorn , G. Heald , J. W. T. Hessels , M. Hoeft , J. Horandel , A. Horneffer , A. van der Horst , M. Iacobelli , E. Juette , A. Karastergiou , V. I. Kondratiev , M. Kramer , M. Kuniyoshi , G. Kuper , J. van Leeuwen , P. Maat , G. Mann , D. McKay-Bukowski , J. P. McKean , H. Munk , A. Nelles , M. J. Norden , H. Paas , M. Pandey-Pommier , G. Pietka , R. Pizzo , A. G. Polatidis , W. Reich , H. Rottgering , A. Rowlinson , A. M. M. Scaife , D. Schwarz , M. Serylak , O. Smirnov , M. Steinmetz , A. Stewart , M. Tagger , Y. Tang , C. Tasse , S. ter Veen , S. Thoudam , C. Toribio , R. Vermeulen , C. Vocks , R. J. van Weeren , R. A. M. J. Wijers , S. J. Wijnholds , O. Wucknitz , P. Zarka

Polarimetric observations of Fast Radio Bursts (FRBs) are a powerful resource for better understanding these mysterious sources by directly probing the emission mechanism of the source and the magneto-ionic properties of its environment. We…

The LOFAR Two-metre Sky Survey (LoTSS) is a sensitive, high-resolution 120-168 MHz survey of the Northern sky. The LoTSS First Data Release (DR1) presents 424 square degrees of radio continuum observations over the HETDEX Spring Field…

We present an overview of the LOFAR Tied-Array All-Sky Survey (LOTAAS) for radio pulsars and fast transients. The survey uses the high-band antennas of the LOFAR Superterp, the dense inner part of the LOFAR core, to survey the northern sky…