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相关论文: CSSs in a sample of B2 radio sources of intermedia…

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We present the results of 5-GHz observations with the VLA A-array of a sample of candidate Compact Steep Spectrum sources (CSSs) selected from the S4 survey. We also estimate the symmetry parameters of high-luminosity CSSs selected from…

天体物理学 · 物理学 2009-10-31 D. J. Saikia , S. Jeyakumar , C. J. Salter , P. Thomasson , R. E. Spencer , F. Mantovani

VLBA observations at 18 cm are presented for 28 Compact Steep-spectrum radio Sources (CSSs) from the B3-VLA CSS sample. These sources were unresolved in previous VLA observations at high frequencies or their brightness distribution was…

天体物理学 · 物理学 2009-11-07 D. Dallacasa , S. Tinti , C. Fanti , R. Fanti , L. Gregorini , C. Stanghellini , M. Vigotti

Global VLBI observations at 5 GHz have been performed to study the source morphology in 10 compact steep-spectrum (CSS) sources selected from the Peacock & Wall catalogue with the aim of finding asymmetric structures produced by the…

宇宙学与河外天体物理 · 物理学 2015-06-15 D. Dallacasa , M. Orienti , C. Fanti , R. Fanti , C. Stanghellini

Compact symmetric objects (CSOs) are intrinsically compact extragalactic radio sources that are thought to be the progenitors of classical radio galaxies. To date, evolutionary models have mainly focused on the formation and growth of…

星系天体物理 · 物理学 2025-05-07 M. Orienti , F. D'Ammando , D. Dallacasa , G. Migliori , P. Rossi , G. Bodo

A small sample of 7 southern Compact Steep Spectrum (CSS) radio sources has been selected as part of the study of a larger flux-limited complete sample of radio sources. High resolution images, using the VLBI network in the southern…

Aims - We report new Very Large Array polarimetric observations of Compact Steep-Spectrum (CSS) sources at 8.4, 15, and 23GHz. Methods - Using multi-frequency VLA observations we have derived sub-arcsecond resolution images of the total…

宇宙学与河外天体物理 · 物理学 2015-06-15 F. Mantovani , A. Rossetti , W. Junor , D. J. Saikia , C. J. Salter

We present a new sample of Compact Steep Spectrum (CSS) sources with radio luminosity below 10^26 W/Hz at 1.4 GHz called the low luminosity compact (LLC) objects. The sources have been selected from FIRST survey and observed with MERLIN at…

宇宙学与河外天体物理 · 物理学 2015-05-20 M. Kunert-Bajraszewska , M. P. Gawronski , A. Labiano , A. Siemiginowska

Based on the FIRST and SDSS catalogues a flux density limited sample of weak Compact Steep Spectrum (CSS) sources with radio luminosity below 10^26 [W/Hz] at 1.4 GHz has been constructed. Our previous multifrequency observations of CSS…

宇宙学与河外天体物理 · 物理学 2010-11-11 Magdalena Kunert-Bajraszewska , Peter Thomasson

A new sample of candidate Compact Steep Spectrum (CSS) sources that are much weaker than the CSS source prototypes has been selected from the VLA FIRST catalogue. MERLIN `snapshot' observations of the sources at 5 GHz indicate that six of…

天体物理学 · 物理学 2009-11-11 Magdalena Kunert-Bajraszewska , Andrzej Marecki , Peter Thomasson , Ralph E. Spencer

According to a generally accepted paradigm, small intrinsic sizes of Compact Steep Spectrum (CSS) radio sources are a direct consequence of their youth, but in later stages of their evolution they are believed to become large-scale sources.…

天体物理学 · 物理学 2009-11-13 Andrzej Marecki , Magdalena Kunert-Bajraszewska , Ralph E. Spencer

Compact steep-spectrum radio sources and giga-hertz peaked spectrum radio sources (CSS/GPS) are generally considered to be mostly young radio sources. In recent years we studied at many wavelengths a sample of these objects selected from…

宇宙学与河外天体物理 · 物理学 2015-05-27 C. Fanti , R. Fanti , A. Zanichelli , D. Dallacasa , C. Stanghellini

Compact Steep Spectrum (CSS) sources are powerful extragalactic radio sources with angular dimensions of the order of a few arcseconds or less. Such a compactness is apparently linked to the youth of these objects. The majority of CSSs…

天体物理学 · 物理学 2009-11-07 M. Kunert , A. Marecki , R. E. Spencer , A. J. Kus , J. Niezgoda

Among radio galaxies, compact sources are a class of objects not yet well understood, and most of them cannot be included in classical populations of compact radio sources (flat spectrum AGN or compact steep spectrum sources). Our main goal…

宇宙学与河外天体物理 · 物理学 2015-06-11 E. Liuzzo , S. Buttiglione , G. Giovannini , M. Giroletti , S. Capetti , G. B. Taylor

Compact Steep Spectrum (CSS) and Gigahertz Peaked Spectrum (GPS) sources are classes of compact, powerful, extragalactic objects. These sources are thought to be the earliest stages in the evolution of radio galaxies, capturing the ignition…

宇宙学与河外天体物理 · 物理学 2015-05-28 Kate E. Randall , Andrew M. Hopkins , Ray P. Norris , Philip G. Edwards

The incidence of young but fading radio sources provides important information on the life cycle of radio emission in radio-loud active galactic nuclei. Despite its importance for constraining the models of radio source evolution, there are…

星系天体物理 · 物理学 2023-05-03 M. Orienti , M. Murgia , D. Dallacasa , G. Migliori , F. D'Ammando

We present results of EVN observations of eleven GHz-Peaked-Spectrum (GPS) radio sources at 2.3/8.4 GHz. These sources are from the classical ''bright'' GPS source samples with peak flux densities $>$ 0.2 Jy and spectral indices $\alpha <…

天体物理学 · 物理学 2007-05-23 L. Xiang , D. Dallacasa , P. Cassaro , D. Jiang , C. Reynolds

Compact steep-spectrum (CSS) and peaked spectrum (PS) radio sources are compact, powerful radio sources. The multi-frequency observational properties and current theories are reviewed with emphasis on developments since the earlier review…

星系天体物理 · 物理学 2021-04-07 Christopher P. O'Dea , D. J. Saikia

We report results on multi-epoch Very Large Array (VLA) and pc-scale Very Long Baseline Array (VLBA) observations of candidate compact symmetric objects (CSOs) from the faint sample of high frequency peakers. New VLBA observations could…

星系天体物理 · 物理学 2020-09-30 M. Orienti , D. Dallacasa

We present observations at 1.7 and 8.4 GHz of two Compact Steep Spectrum (CSS) sources from a complete sample of low-intermediate power radio galaxies. 3C346 shows an asymmetric structure with a one-sided ``jet'' and ``hot spot''. Present…

天体物理学 · 物理学 2009-10-28 W. D. Cotton , L. Feretti , G. Giovannini , T. Venturi , L. Lara , J. Marcaide , A. E. Wehrle

The Compact Symmetric Objects (CSOs) are small (<1 kiloparsec) and powerful extragalactic radio sources showing emission on both sides of an active galactic nucleus and no signs of strong relativistic beaming. They may be young radio…

宇宙学与河外天体物理 · 物理学 2011-12-20 K. V. Sokolovsky , Y. Y. Kovalev , A. B. Pushkarev , P. Mimica , M. Perucho
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