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Related papers: Spectral Ages of CSOs and CSS Sources

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We present Chandra and XMM-Newton X-ray, VLA radio, and optical observations of three candidate Compact Steep Spectrum (CSS) radio galaxies. CSS sources are galactic scale and are presumably driving a shock through the ISM of their host…

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.…

Astrophysics · Physics 2009-11-13 M. Orienti , D. Dallacasa , C. Stanghellini

This paper presents theoretical integrated spectral energy distributions (SEDs) of binary star composite stellar populations (bsCSPs) in early-type galaxies, and how the bsCSP model can be used for spectral studies of galaxies. All bsCSPs…

Astrophysics of Galaxies · Physics 2015-06-05 Zhongmu Li , Liyun Zhang , Jinzhong Liu

We present a study of the trends in luminosity, linear size, spectral index, and redshift of classical double radio sources from three complete samples selected at successively fainter low radio-frequency flux-limits. We have been able to…

Astrophysics · Physics 2010-04-06 Katherine M. Blundell , Steve Rawlings , Chris J. Willott

Low frequency observations at 330 and 74 MHz can provide new insights into supernova remnants (SNR). We can test theoretical predictions for spectral index variations. Nonlinear models of shock acceleration predict that the spectra from…

Astrophysics · Physics 2007-05-23 Kristy K. Dyer , Stephen P. Reynolds , Kazik J. Borkowski

The mean ages of early-type galaxies obtained from the analysis of optical spectra, give a mean age of 8 Gyr at z = 0, with 40% being younger than 6 Gyr. Independent age determinations are possible by using infrared spectra (5-21 microns),…

Astrophysics · Physics 2008-11-26 Joel N. Bregman , Pasquale Temi , Jesse D. Bregman

We present pc-scale images of ten Compact Symmetric Objects (CSO) candidates observed with the European VLBI network (EVN). Five radio sources have been observed at 1.6 GHz, and five more at 2.3/8.4 GHz, the latter subsample with the…

Astrophysics · Physics 2009-11-07 Liu Xiang , Carlo Stanghellini , Daniele Dallacasa , Zhang Haiyan

Nearby sources may contribute to cosmic-ray electron (CRE) structures at high energies. Recently, the first DAMPE results on the CRE flux hinted at a narrow excess at energy ~1.4 TeV. We show that in general a spectral structure with a…

High Energy Astrophysical Phenomena · Physics 2018-05-09 Xian-Jun Huang , Yue-Liang Wu , Wei-Hong Zhang , Yu-Feng Zhou

EVN and MERLIN observations at 18 cm are presented for 18 Compact Steep--spectrum radio Sources (CSSs) from the B3-VLA CSS sample. These sources were marginally resolved in previous VLA A-configuration observations at 4.9 and 8.4 GHz or had…

Astrophysics · Physics 2009-11-07 D. Dallacasa , C. Fanti , S. Giacintucci , C. Stanghellini , R. Fanti , L. Gregorini , M. Vigotti

We present $K$-band integral field spectroscopic observations towards 17 massive young stellar objects (YSOs) in the low metallicity Small Magellanic Cloud (SMC) and two YSO candidates in the compact H ii regions N81 and N88 A (also in the…

Astrophysics of Galaxies · Physics 2016-09-21 J. L. Ward , J. M. Oliveira , J. Th. van Loon , M. Sewiło

I will review some of the developments in studies of the host galaxy properties of Compact Steep Spectrum (CSS) and GigaHertz-Peaked Spectrum (GPS) radio sources. In contrast to previous reviews structured around observational technique, I…

Astrophysics · Physics 2009-11-13 J. Holt

Synchrotron radiation from supernova remnants are caused by electrons accelerated through diffusive shock acceleration (DSA). The standard DSA theory predicts an electron spectral index of $p=2$, corresponding to a radio spectral index of…

High Energy Astrophysical Phenomena · Physics 2021-02-10 V. Domček , J. Vink , J. V. Hernández Santisteban , T. Delaney , P. Zhou

As a constraint for new starburst/AGN models of IRAS bright galaxies we determine the radio spectra of 31 luminous and ultraluminous IRAS galaxies (LIRGs/ULIRGs). We construct the radio spectra using both new and archival data. From our…

Astrophysics · Physics 2009-11-13 M. S. Clemens , O. Vega , A. Bressan , G. L. Granato , L. Silva , P. Panuzzo

Optical and near-infrared variability is a well-known property of young stellar objects. However, a growing number of recent studies claim that a considerable fraction of them also exhibit mid-infrared flux changes. With the aim of studying…

Solar and Stellar Astrophysics · Physics 2015-06-04 Á. Kóspál , P. Ábrahám , J. A. Acosta-Pulido , C. P. Dullemond , Th. Henning , M. Kun , Ch. Leinert , A. Moór , N. J. Turner

We present the first systematic search for UV signatures from radio source-driven AGN feedback in Compact Steep Spectrum (CSS) radio galaxies. Owing to their characteristic sub-galactic jets (1-20 kpc projected linear sizes), CSS hosts are…

Steep spectrum radio sources associated with active galactic nuclei (AGN) may contain remnants of past AGN activity episodes. Novel instruments like the LOw Frequency ARray (LOFAR) are enabling studies of these fascinating structures to be…

We present new images of the Supernova Remnant (SNR) G127.1+0.5 (R5), based on the 408 MHz and 1420 MHz continuum emission and the HI-line emission data of the Canadian Galactic Plane Survey (CGPS). The radio spectrum of the central compact…

Astrophysics · Physics 2009-11-11 Denis A. Leahy , Wenwu Tian

We observed with the VLBA at 2.3 and 8.6 GHz a complete flux-density limited sample of 482 radio sources with declination >+75 degrees brighter than 200 mJy at 1.4 GHz drawn from the NVSS catalog. 34% of the sources show parsec-scale…

Astrophysics of Galaxies · Physics 2021-02-01 Alexander V. Popkov , Yuri Y. Kovalev , Leonid Y. Petrov , Yuri A. Kovalev

We highlight differences in spectral types and intrinsic colors observed in pre-main sequence (pre-MS) stars. Spectral types of pre-MS stars are wavelength-dependent, with near-infrared spectra being 3-5 spectral sub-classes later than the…

Solar and Stellar Astrophysics · Physics 2016-07-14 Mark J. Pecaut

During the last few years a number of works have proposed that planetary harmonics regulate solar oscillations and the Earth climate. Herein I address some critiques. Detailed analysis of the data do support the planetary theory of solar…

Geophysics · Physics 2014-12-02 Nicola Scafetta