skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources

Abstract

Spectral energy distributions (SEDs) and radio continuum spectra are presented for a northern sample of 104 extragalactic radio sources, based on the Planck Early Release Compact Source Catalogue (ERCSC) and simultaneous multifrequency data. The nine Planck frequencies, from 30 to 857GHz, are complemented by a set of simultaneous observations ranging from radio to gamma-rays. This is the first extensive frequency coverage in the radio and millimetre domains for an essentially complete sample of extragalactic radio sources, and it shows how the individual shocks, each in their own phase of development, shape the radio spectra as they move in the relativistic jet. The SEDs presented in this paper were fitted with second and third degree polynomials to estimate the frequencies of the synchrotron and inverse Compton (IC) peaks, and the spectral indices of low and high frequency radio data, including the Planck ERCSC data, were calculated. SED modelling methods are discussed, with an emphasis on proper, physical modelling of the synchrotron bump using multiple components. Planck ERCSC data also suggest that the original accelerated electron energy spectrum could be much harder than commonly thought, with power-law index around 1.5 instead of the canonical 2.5. The implications of this are discussed formore » the acceleration mechanisms effective in blazar shock. Furthermore in many cases the Planck data indicate that gamma-ray emission must originate in the same shocks that produce the radio emission.« less

Authors:
 [1]
  1. Aalto Univ., Otaniemi (Finland); et al.
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
Contributing Org.:
Planck Collaboration
OSTI Identifier:
1356776
Grant/Contract Number:  
AC02-76SF00515
Resource Type:
Accepted Manuscript
Journal Name:
Astronomy and Astrophysics
Additional Journal Information:
Journal Volume: 536; Journal ID: ISSN 0004-6361
Publisher:
EDP Sciences
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Aatrokoski, J. Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources. United States: N. p., 2011. Web. doi:10.1051/0004-6361/201116466.
Aatrokoski, J. Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources. United States. doi:10.1051/0004-6361/201116466.
Aatrokoski, J. Thu . "Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources". United States. doi:10.1051/0004-6361/201116466. https://www.osti.gov/servlets/purl/1356776.
@article{osti_1356776,
title = {Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources},
author = {Aatrokoski, J.},
abstractNote = {Spectral energy distributions (SEDs) and radio continuum spectra are presented for a northern sample of 104 extragalactic radio sources, based on the Planck Early Release Compact Source Catalogue (ERCSC) and simultaneous multifrequency data. The nine Planck frequencies, from 30 to 857GHz, are complemented by a set of simultaneous observations ranging from radio to gamma-rays. This is the first extensive frequency coverage in the radio and millimetre domains for an essentially complete sample of extragalactic radio sources, and it shows how the individual shocks, each in their own phase of development, shape the radio spectra as they move in the relativistic jet. The SEDs presented in this paper were fitted with second and third degree polynomials to estimate the frequencies of the synchrotron and inverse Compton (IC) peaks, and the spectral indices of low and high frequency radio data, including the Planck ERCSC data, were calculated. SED modelling methods are discussed, with an emphasis on proper, physical modelling of the synchrotron bump using multiple components. Planck ERCSC data also suggest that the original accelerated electron energy spectrum could be much harder than commonly thought, with power-law index around 1.5 instead of the canonical 2.5. The implications of this are discussed for the acceleration mechanisms effective in blazar shock. Furthermore in many cases the Planck data indicate that gamma-ray emission must originate in the same shocks that produce the radio emission.},
doi = {10.1051/0004-6361/201116466},
journal = {Astronomy and Astrophysics},
number = ,
volume = 536,
place = {United States},
year = {2011},
month = {12}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 75 works
Citation information provided by
Web of Science

Save / Share: