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AGN duty cycle estimates for the ultra-steep spectrum radio relic VLSS J1431.8+1331. / Shulevski, A.; Morganti, R.; Barthel, P. D.; Harwood, J. J.; Brunetti, G.; Van Weeren, R. J.; Röttgering, H. J.A.; White, G. J.; Horellou, C.; Kunert-Bajraszewska, M.; Jamrozy, M.; Chyzy, K. T.; Mahony, E.; Miley, G.; Brienza, M.; Bîrzan, L.; Rafferty, D. A.; Brüggen, M.; Wise, M. W.; Conway, J.; De Gasperin, F.; Vilchez, N.

In: Astronomy and Astrophysics, Vol. 583, A89, 01.11.2015.

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Harvard

Shulevski, A, Morganti, R, Barthel, PD, Harwood, JJ, Brunetti, G, Van Weeren, RJ, Röttgering, HJA, White, GJ, Horellou, C, Kunert-Bajraszewska, M, Jamrozy, M, Chyzy, KT, Mahony, E, Miley, G, Brienza, M, Bîrzan, L, Rafferty, DA, Brüggen, M, Wise, MW, Conway, J, De Gasperin, F & Vilchez, N 2015, 'AGN duty cycle estimates for the ultra-steep spectrum radio relic VLSS J1431.8+1331', Astronomy and Astrophysics, vol. 583, A89. https://doi.org/10.1051/0004-6361/201525632

APA

Shulevski, A., Morganti, R., Barthel, P. D., Harwood, J. J., Brunetti, G., Van Weeren, R. J., Röttgering, H. J. A., White, G. J., Horellou, C., Kunert-Bajraszewska, M., Jamrozy, M., Chyzy, K. T., Mahony, E., Miley, G., Brienza, M., Bîrzan, L., Rafferty, D. A., Brüggen, M., Wise, M. W., ... Vilchez, N. (2015). AGN duty cycle estimates for the ultra-steep spectrum radio relic VLSS J1431.8+1331. Astronomy and Astrophysics, 583, [A89]. https://doi.org/10.1051/0004-6361/201525632

Vancouver

Author

Shulevski, A. ; Morganti, R. ; Barthel, P. D. ; Harwood, J. J. ; Brunetti, G. ; Van Weeren, R. J. ; Röttgering, H. J.A. ; White, G. J. ; Horellou, C. ; Kunert-Bajraszewska, M. ; Jamrozy, M. ; Chyzy, K. T. ; Mahony, E. ; Miley, G. ; Brienza, M. ; Bîrzan, L. ; Rafferty, D. A. ; Brüggen, M. ; Wise, M. W. ; Conway, J. ; De Gasperin, F. ; Vilchez, N. / AGN duty cycle estimates for the ultra-steep spectrum radio relic VLSS J1431.8+1331. In: Astronomy and Astrophysics. 2015 ; Vol. 583.

Bibtex

@article{829d007007514ed2a79e5f2ceaa7aa19,
title = "AGN duty cycle estimates for the ultra-steep spectrum radio relic VLSS J1431.8+1331",
abstract = "Context. Steep spectrum radio sources associated with active galactic nuclei (AGN) may contain remnants of past AGN activity episodes. Studying these sources gives us insight into the AGN activity history. Novel instruments like the LOw Frequency ARray (LOFAR) are enabling studies of these fascinating structures to be made at tens to hundreds of MHz with sufficient resolution to analyse their complex morphology. Aims. Our goal is to characterize the integrated and resolved spectral properties of VLSS J1431+1331 and estimate source ages based on synchrotron radio emission models, thus putting constraints on the AGN duty cycle. Methods. Using a broad spectral coverage, we have derived spectral and curvature maps, and used synchrotron ageing models to determine the time elapsed from the last time the source plasma was energized. We used LOFAR, Giant Metrewave Radio Telescope (GMRT) and Jansky Very Large Array (VLA) data. Results. We confirm the morphology and the spectral index values found in previous studies of this object. Based on our ageing analysis, we infer that the AGN that created this source currently has very low levels of activity or that it is switched off. The derived ages for the larger source component range from around 60 to 130 Myr, hinting that the AGN activity decreased or stopped around 60 Myr ago. We observe that the area around the faint radio core located in the larger source component is the youngest, while the overall age of the smaller source component shows it to be the oldest part of the source. Conclusions. Our analysis suggests that VLSS J1431.8+1331 is an intriguing, two-component source. The larger component seems to host a faint radio core, suggesting that the source may be an AGN radio relic. The spectral index we observe from the smaller component is distinctly flatter at lower frequencies than the spectral index of the larger component, suggesting the possibility that the smaller component may be a shocked plasma bubble. From the integrated source spectrum, we deduce that its shape and slope can be used as tracers of the activity history of this type of steep spectrum radio source. We discuss the implications this conclusion has for future studies of radio sources having similar characteristics.",
keywords = "Galaxies: active, Galaxies: individual: VLSS J1431.8+1331, Radio continuum: galaxies",
author = "A. Shulevski and R. Morganti and Barthel, {P. D.} and Harwood, {J. J.} and G. Brunetti and {Van Weeren}, {R. J.} and R{\"o}ttgering, {H. J.A.} and White, {G. J.} and C. Horellou and M. Kunert-Bajraszewska and M. Jamrozy and Chyzy, {K. T.} and E. Mahony and G. Miley and M. Brienza and L. B{\^i}rzan and Rafferty, {D. A.} and M. Br{\"u}ggen and Wise, {M. W.} and J. Conway and {De Gasperin}, F. and N. Vilchez",
note = "Reproduced with permission from Astronomy & Astrophysics. {\textcopyright} 2018 ESO.",
year = "2015",
month = nov,
day = "1",
doi = "10.1051/0004-6361/201525632",
language = "English",
volume = "583",
journal = "Astronomy & Astrophysics",
issn = "0004-6361",
publisher = "EDP Sciences",

}

RIS

TY - JOUR

T1 - AGN duty cycle estimates for the ultra-steep spectrum radio relic VLSS J1431.8+1331

AU - Shulevski, A.

AU - Morganti, R.

AU - Barthel, P. D.

AU - Harwood, J. J.

AU - Brunetti, G.

AU - Van Weeren, R. J.

AU - Röttgering, H. J.A.

AU - White, G. J.

AU - Horellou, C.

AU - Kunert-Bajraszewska, M.

AU - Jamrozy, M.

AU - Chyzy, K. T.

AU - Mahony, E.

AU - Miley, G.

AU - Brienza, M.

AU - Bîrzan, L.

AU - Rafferty, D. A.

AU - Brüggen, M.

AU - Wise, M. W.

AU - Conway, J.

AU - De Gasperin, F.

AU - Vilchez, N.

N1 - Reproduced with permission from Astronomy & Astrophysics. © 2018 ESO.

PY - 2015/11/1

Y1 - 2015/11/1

N2 - Context. Steep spectrum radio sources associated with active galactic nuclei (AGN) may contain remnants of past AGN activity episodes. Studying these sources gives us insight into the AGN activity history. Novel instruments like the LOw Frequency ARray (LOFAR) are enabling studies of these fascinating structures to be made at tens to hundreds of MHz with sufficient resolution to analyse their complex morphology. Aims. Our goal is to characterize the integrated and resolved spectral properties of VLSS J1431+1331 and estimate source ages based on synchrotron radio emission models, thus putting constraints on the AGN duty cycle. Methods. Using a broad spectral coverage, we have derived spectral and curvature maps, and used synchrotron ageing models to determine the time elapsed from the last time the source plasma was energized. We used LOFAR, Giant Metrewave Radio Telescope (GMRT) and Jansky Very Large Array (VLA) data. Results. We confirm the morphology and the spectral index values found in previous studies of this object. Based on our ageing analysis, we infer that the AGN that created this source currently has very low levels of activity or that it is switched off. The derived ages for the larger source component range from around 60 to 130 Myr, hinting that the AGN activity decreased or stopped around 60 Myr ago. We observe that the area around the faint radio core located in the larger source component is the youngest, while the overall age of the smaller source component shows it to be the oldest part of the source. Conclusions. Our analysis suggests that VLSS J1431.8+1331 is an intriguing, two-component source. The larger component seems to host a faint radio core, suggesting that the source may be an AGN radio relic. The spectral index we observe from the smaller component is distinctly flatter at lower frequencies than the spectral index of the larger component, suggesting the possibility that the smaller component may be a shocked plasma bubble. From the integrated source spectrum, we deduce that its shape and slope can be used as tracers of the activity history of this type of steep spectrum radio source. We discuss the implications this conclusion has for future studies of radio sources having similar characteristics.

AB - Context. Steep spectrum radio sources associated with active galactic nuclei (AGN) may contain remnants of past AGN activity episodes. Studying these sources gives us insight into the AGN activity history. Novel instruments like the LOw Frequency ARray (LOFAR) are enabling studies of these fascinating structures to be made at tens to hundreds of MHz with sufficient resolution to analyse their complex morphology. Aims. Our goal is to characterize the integrated and resolved spectral properties of VLSS J1431+1331 and estimate source ages based on synchrotron radio emission models, thus putting constraints on the AGN duty cycle. Methods. Using a broad spectral coverage, we have derived spectral and curvature maps, and used synchrotron ageing models to determine the time elapsed from the last time the source plasma was energized. We used LOFAR, Giant Metrewave Radio Telescope (GMRT) and Jansky Very Large Array (VLA) data. Results. We confirm the morphology and the spectral index values found in previous studies of this object. Based on our ageing analysis, we infer that the AGN that created this source currently has very low levels of activity or that it is switched off. The derived ages for the larger source component range from around 60 to 130 Myr, hinting that the AGN activity decreased or stopped around 60 Myr ago. We observe that the area around the faint radio core located in the larger source component is the youngest, while the overall age of the smaller source component shows it to be the oldest part of the source. Conclusions. Our analysis suggests that VLSS J1431.8+1331 is an intriguing, two-component source. The larger component seems to host a faint radio core, suggesting that the source may be an AGN radio relic. The spectral index we observe from the smaller component is distinctly flatter at lower frequencies than the spectral index of the larger component, suggesting the possibility that the smaller component may be a shocked plasma bubble. From the integrated source spectrum, we deduce that its shape and slope can be used as tracers of the activity history of this type of steep spectrum radio source. We discuss the implications this conclusion has for future studies of radio sources having similar characteristics.

KW - Galaxies: active

KW - Galaxies: individual: VLSS J1431.8+1331

KW - Radio continuum: galaxies

UR - http://www.scopus.com/inward/record.url?scp=84946548568&partnerID=8YFLogxK

U2 - 10.1051/0004-6361/201525632

DO - 10.1051/0004-6361/201525632

M3 - Article

AN - SCOPUS:84946548568

VL - 583

JO - Astronomy & Astrophysics

JF - Astronomy & Astrophysics

SN - 0004-6361

M1 - A89

ER -