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相关论文: Polarimetric imaging with the GMRT

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Much data on the Galactic polarized radio emission has been gathered in the last five decades. All-sky surveys have been made, but only in narrow, widely spaced frequency bands, and the data are inadequate for the characterization of…

We present polarization measurements of extragalactic radio sources observed during the Cosmic Microwave Background polarization survey of the Q/U Imaging Experiment (QUIET), operating at 43 GHz (Q-band) and 95 GHz (W-band). We examine…

SPOrt (Sky Polarization Observatory) is a space experiment to be flown on the International Space Station during Early Utilization Phase aimed at measuring the microwave polarized emission with FWHM = 7deg, in the frequency range 22-90 GHz.…

Radio galaxies are linearly polarized -- an important property that allows us to infer the properties of the magnetic field of the source and its environment. However at low frequencies, Faraday rotation substantially depolarizes the…

The low-frequency polarisation properties of radio sources are poorly studied, particularly in statistical samples. However, the new generation of low-frequency telescopes, such as the Murchison Widefield Array (MWA; the precursor for the…

The GMRT reionization effort aims to map out the large scale structure of the Universe during the epoch of reionization (EoR). Removal of polarized Galactic emission is a difficult part of any 21 cm EoR program, and we present new upper…

Polarization measurements of the gamma-ray component of transient sources are of great scientific interest, they are however, also highly challenging. This is due to the typical low signal to noise and the potential for significant…

天体物理仪器与方法 · 物理学 2023-04-05 Merlin Kole , Jianchao Sun

We obtained optical imaging polarimetry with the ACS/HRC aboard the HST of the 9 closest radio-galaxies in the 3C catalogue with an FR I morphology. The nuclear sources seen in direct HST images in these galaxies are found to be highly…

The polarisation properties of the intrinsically small (< 20 kpc) radio sources are briefly discussed. At centimetric and decimetric wavelengths, substantial polarised emission is often detected in quasars and, at a lower level, in radio…

天体物理学 · 物理学 2007-05-23 D. Dallacasa

We present a method to simulate the polarization properties of extragalactic radio sources at microwave frequencies. Polarization measurements of nearly 2x10^6 sources at 1.4 GHz are provided by the NVSS survey. Using this catalogue and the…

天体物理学 · 物理学 2008-11-26 M. Tucci , E. Martinez-Gonzalez , L. Toffolatti , J. Gonzalez-Nuevo , G. De Zotti

Short millimeter observations of radio-loud AGN offer the opportunity to study the physics of their inner relativistic jets, from where the bulk millimeter emission is radiated. Millimeter jets are significantly less affected by Faraday…

星系天体物理 · 物理学 2014-07-02 I. Agudo , C. Thum , J. L. Gomez , H. Wiesemeyer

We describe the design and performance of a microwave polarimeter used to make precision measurements of polarized astrophysical radiation in three microwave frequency bands spanning 26-36 GHz. The instrument uses cooled HEMT amplifiers in…

As radio polarised emission from astrophysical objects traverse through foreground magnetised plasma, the physical conditions along the lines of sight are encrypted in the form of Rotation Measure (RM). We performed broadband…

星系天体物理 · 物理学 2017-10-10 Yik Ki Ma , Sui Ann Mao , Aritra Basu , Carl Heiles , Jennifer West

The ability of NICMOS to perform high accuracy polarimetry is currently hampered by an uncalibrated residual instrumental polarization at a level of 1.2-1.5%. To better quantify and characterize this residual we obtained observations of…

天体物理学 · 物理学 2008-11-07 D. Batcheldor , G. Schneider , D. C. Hines , G. D. Schmidt , D. J. Axon , A. Robinson , W. Sparks , C. Tadhunter

We present the largest ever sample of radio polarization properties for $z>4$ sources, with 14 sources having significant polarization detections. Using wideband data from the Karl G. Jansky Very Large Array, we obtained the rest-frame…

星系天体物理 · 物理学 2018-02-07 Tessa Vernstrom , Bryan Gaensler , Valentina Vacca , Jamie Farnes , Marijke Haverkorn , Shane O'Sullivan

Polarisation measurements of solar flares at millimetre-waves were used to investigate the magnetic field configuration of the emitting sources. We analyse two solar flares (SOL2013-02-17 and SOL2013-11-05) observed by the POlarisation…

太阳与恒星天体物理 · 物理学 2020-05-05 Douglas F. da Silva , Paulo J. A. Simões , R. F. Hidalgo Ramírez , Adriana Válio

The technique of Faraday tomography is a key tool for the study of magnetised plasmas in the new era of broadband radio polarisation observations. In particular, observations at metre-wavelengths provide significantly better Faraday depth…

The MIT X-ray Polarimetry Beamline is a facility that we developed for testing components for possible use in X-ray polarimetry. Over the past few years, we have demonstrated that the X-ray source can generate nearly 100% polarized X-rays…

天体物理仪器与方法 · 物理学 2024-08-22 Sarah N. T. Heine , Herman L. Marshall , Benjamin Schneider , Beverly Lamar , Nithya Kothnur , Alan Garner

The nature of the prompt gamma-ray emission of Gamma-Ray Bursts (GRBs) is still far from being completely elucidated. The measure of linear polarization is a powerful tool that can be used to put further constraints on the content and…

高能天体物理现象 · 物理学 2015-06-22 D. Gotz , P. Laurent , S. Antier , S. Covino , P. D'Avanzo , V. D'Elia , A. Melandri

Simultaneous $\gamma$-ray measurements of gamma-ray burst (GRB) spectra and polarization offer a unique way to determine the underlying emission mechanism(s) in these objects as well as probing the particle acceleration mechanism(s) that…

高能天体物理现象 · 物理学 2019-08-13 J. Michael Burgess , M. Kole , F. Berlato , J. Greiner , G. Vianello , N. Produit , Z. H Li , J. C Sun