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相关论文: Constraining the nature of High Frequency Peakers.…

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We present new, simultaneous, multifrequency observations of 45 out of the 55 candidate High Frequency Peakers (HFP) selected by Dallacasa et al. (2000), carried out 3 to 4 years after a first set of observations. Our sub-sample consists of…

天体物理学 · 物理学 2009-11-10 S. Tinti , D. Dallacasa , G. De Zotti , A. Celotti , C. Stanghellini

We investigate the spectral characteristics of 51 candidate High Frequency Peakers (HFPs), from the ``bright'' HFP sample, in order to determine the nature of each object, and to obtain a smaller sample of genuine young radio sources.…

天体物理学 · 物理学 2009-11-13 M. Orienti , D. Dallacasa , C. Stanghellini

We propose a morphological classification based on the parsec scale structure of fifty-one High Frequency Peakers (HFPs) from the ``bright'' HFP sample. VLBA images at two adjacent frequencies (chosen among 8.4, 15.3, 22.2 and 43.2 GHz)…

天体物理学 · 物理学 2009-11-11 M. Orienti , D. Dallacasa , S. Tinti , C. Stanghellini

We present CCD observations of 13 objects from a complete sample of 55 bright High Frequency Peaker (HFP) radio sources, and provide optical identification for 12 of them. Images in R and V filters have been used to derive some additional…

天体物理学 · 物理学 2009-11-07 D. Dallacasa , R. Falomo , C. Stanghellini

We present the results of second epoch simultaneous multifrequency observations of 45 sources out of the 55 in the sample of High Frequency Peakers (HFP) by Dallacasa et al. (2000). Seven of the stellar sources (i.e. 16% of the total number…

天体物理学 · 物理学 2007-05-23 S. Tinti , D. Dallacasa , G. De Zotti , C. Stanghellini , A. Celotti

Here we present a sample of sources with convex radio spectra peaking at frequencies above a few GHz. We call these radio sources High Frequency Peakers (HFPs). This sample extends to higher turnover frequencies than the samples of Compact…

天体物理学 · 物理学 2016-08-30 Daniele Dallacasa , Carlo Stanghellini , Matteo Centonza , Roberto Fanti

We have studied the implications of high sensitivity polarization measurements of objects from the WMAP point source catalogue made using the VLA at 8.4, 22 and 43 GHz. The fractional polarization of sources is almost independent of…

宇宙学与河外天体物理 · 物理学 2015-05-18 R. A. Battye , I. W. A. Browne , M. W. Peel , N. J. Jackson , C. Dickinson

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

A sample of high-frequency peaker (HFP) candidates was formed from the AT20G catalog radio sources with spectral indices of the optically thick emission region $\alpha_{below}$ exceeding +0.5. A study of the spectral properties of the…

宇宙学与河外天体物理 · 物理学 2025-08-12 Elena Majorova , Olga Zhelenkova

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…

We present the analysis of simultaneous multi-frequency Very Large Array (VLA) observations of 57 out of 61 sources from the ``faint'' high frequency peaker (HFP) sample carried out in various epochs. Sloan Digital Sky Survey (SDSS) data…

宇宙学与河外天体物理 · 物理学 2015-05-19 M. Orienti , D. Dallacasa , C. Stanghellini

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 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…

A significant fraction of compact radio-loud quasars display most of the characteristics of relativistically beamed, high-optical polarization blazars, yet are weakly polarized in the optical regime. We have used the VLBA at 22 and 43 GHz…

天体物理学 · 物理学 2009-10-31 Matthew L. Lister , Paul S. Smith

We present flux densities and polarization percentages of 159 radio galaxies based on nearly simultaneous VLA observations at four frequencies from 5 to 43GHz. This sample is selected from the high-frequency Australia Telescope 20GHz…

宇宙学与河外天体物理 · 物理学 2015-03-18 Anna Sajina , Bruce Partridge , Tyler Evans , Shannon Stefl , Nicholas Vechik , Steve Myers , Simon Dicker , Phillip Korngut

We define a complete sample of thirty-three GHz-Peaked-Spectrum (GPS) radio sources based on their spectral properties. We present measurements of the radio spectra and polarization of the complete sample and a list of additional GPS…

天体物理学 · 物理学 2016-08-30 C. Stanghellini , C. P. O'Dea , D. Dallacasa , S. A. Baum , R. Fanti , C. Fanti

We investigate the parsec-scale structure of 17 high frequency peaking radio sources from the faint HFP sample. VLBA observations were carried out at two adjacent frequencies, 8.4 and 15.3 GHz, both in the optically-thin part of the…

宇宙学与河外天体物理 · 物理学 2015-06-05 M. Orienti , D. Dallacasa

We present polarization data for 32 mainly southern pulsars at 8.4 GHz. The observations show that the polarization fraction is low in most pulsars at this frequency except for the young, energetic pulsars which continue to show…

天体物理学 · 物理学 2016-08-16 Simon Johnston , Aris Karastergiou , Kyle Willett

We performed observations with the Effelsberg 100-m radio telescope to measure flux densities and polarised emission of sources selected from the "Deep X-ray Radio Blazar Survey" (DXRBS) to better define their spectral index behaviour in…

宇宙学与河外天体物理 · 物理学 2011-07-28 Franco Mantovani , Marco Bondi , Karl-Heinz Mack

We present a broadband polarization analysis of 36 discrete polarized radio sources over a very broad, densely-sampled frequency band. Our sample was selected on the basis of polarization behaviour apparent in narrowband archival data at…

高能天体物理现象 · 物理学 2016-07-06 C. S. Anderson , B. M. Gaensler , I. J. Feain
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