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Title: Intermittent Jet Activity in the Radio Galaxy 4C29.30?

Abstract

We present radio observations at frequencies ranging from 240 to 8460 MHz of the radio galaxy 4C29.30 (J0840+2949) using the Giant Metrewave Radio Telescope (GMRT), the Very Large Array (VLA) and the Effelsberg telescope. We report the existence of weak extended emission with an angular size of {approx} 520 arcsec (639 kpc) within which a compact edge-brightened double-lobed source with a size of 29 arcsec (36 kpc) is embedded. We determine the spectrum of the inner double from 240 to 8460 MHz and show that it has a single power-law spectrum with a spectral index is {approx} 0.8. Its spectral age is estimated to be 33 Myr. The extended diffuse emission has a steep spectrum with a spectral index of {approx} 1.3 and a break frequency 240 MHz. The spectral age is {approx}>200 Myr, suggesting that the extended diffuse emission is due to an earlier cycle of activity. We reanalyze archival x-ray data from Chandra and suggest that the x-ray emission from the hotspots consists of a mixture of nonthermal and thermal components, the latter being possibly due to gas which is shock heated by the jets from the host galaxy.

Authors:
; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
901849
Report Number(s):
SLAC-PUB-12427
Journal ID: ISSN 0035-8711; MNRAA4; astro-ph/0703723; TRN: US200715%%86
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Mon.Not.Roy.Astron.Soc.
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; RADIO GALAXIES; JETS; EMISSION SPECTRA; AGE ESTIMATION; Astrophysics,ACCPHY

Citation Formats

Jamrozy, M., /Jagiellonian U., Astron. Observ., Konar, C., Saikia, D.J., /NCRA, Ganeshkhind, Stawarz, L., /Jagiellonian U., Astron. Observ. /KIPAC, Menlo Park /SLAC, Mack, K.-H., /Bologna, Ist. Radioastronomia, Siemiginowska, A., and /Harvard-Smithsonian Ctr. Astrophys.. Intermittent Jet Activity in the Radio Galaxy 4C29.30?. United States: N. p., 2007. Web. doi:10.1111/j.1365-2966.2007.11782.x.
Jamrozy, M., /Jagiellonian U., Astron. Observ., Konar, C., Saikia, D.J., /NCRA, Ganeshkhind, Stawarz, L., /Jagiellonian U., Astron. Observ. /KIPAC, Menlo Park /SLAC, Mack, K.-H., /Bologna, Ist. Radioastronomia, Siemiginowska, A., & /Harvard-Smithsonian Ctr. Astrophys.. Intermittent Jet Activity in the Radio Galaxy 4C29.30?. United States. doi:10.1111/j.1365-2966.2007.11782.x.
Jamrozy, M., /Jagiellonian U., Astron. Observ., Konar, C., Saikia, D.J., /NCRA, Ganeshkhind, Stawarz, L., /Jagiellonian U., Astron. Observ. /KIPAC, Menlo Park /SLAC, Mack, K.-H., /Bologna, Ist. Radioastronomia, Siemiginowska, A., and /Harvard-Smithsonian Ctr. Astrophys.. Mon . "Intermittent Jet Activity in the Radio Galaxy 4C29.30?". United States. doi:10.1111/j.1365-2966.2007.11782.x. https://www.osti.gov/servlets/purl/901849.
@article{osti_901849,
title = {Intermittent Jet Activity in the Radio Galaxy 4C29.30?},
author = {Jamrozy, M. and /Jagiellonian U., Astron. Observ. and Konar, C. and Saikia, D.J. and /NCRA, Ganeshkhind and Stawarz, L. and /Jagiellonian U., Astron. Observ. /KIPAC, Menlo Park /SLAC and Mack, K.-H. and /Bologna, Ist. Radioastronomia and Siemiginowska, A. and /Harvard-Smithsonian Ctr. Astrophys.},
abstractNote = {We present radio observations at frequencies ranging from 240 to 8460 MHz of the radio galaxy 4C29.30 (J0840+2949) using the Giant Metrewave Radio Telescope (GMRT), the Very Large Array (VLA) and the Effelsberg telescope. We report the existence of weak extended emission with an angular size of {approx} 520 arcsec (639 kpc) within which a compact edge-brightened double-lobed source with a size of 29 arcsec (36 kpc) is embedded. We determine the spectrum of the inner double from 240 to 8460 MHz and show that it has a single power-law spectrum with a spectral index is {approx} 0.8. Its spectral age is estimated to be 33 Myr. The extended diffuse emission has a steep spectrum with a spectral index of {approx} 1.3 and a break frequency 240 MHz. The spectral age is {approx}>200 Myr, suggesting that the extended diffuse emission is due to an earlier cycle of activity. We reanalyze archival x-ray data from Chandra and suggest that the x-ray emission from the hotspots consists of a mixture of nonthermal and thermal components, the latter being possibly due to gas which is shock heated by the jets from the host galaxy.},
doi = {10.1111/j.1365-2966.2007.11782.x},
journal = {Mon.Not.Roy.Astron.Soc.},
number = ,
volume = ,
place = {United States},
year = {Mon Apr 02 00:00:00 EDT 2007},
month = {Mon Apr 02 00:00:00 EDT 2007}
}
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