TY - JOUR
T1 - Studying the late evolution of a radio-loud AGN in a galaxy group with LOFAR
AU - Savini, F.
AU - Bonafede, Annalisa
AU - Brüggen, M.
AU - Wilber, A.
AU - Harwood, Jeremy J.
AU - Murgia, M.
AU - Shimwell, T. W.
AU - Rafferty, D. A.
AU - Shulevski, Aleksandar
AU - Brienza, M.
AU - Hardcastle, M. J.
AU - Morganti, Raffaella
AU - Röttgering, Huub
AU - Clarke, A. O.
AU - De Gasperin, Francesco
AU - van Weeren, R. J.
AU - Best, P. N.
AU - Botteon, A.
AU - Brunetti, Gianfranco
AU - Cassano, R.
PY - 2017/11/7
Y1 - 2017/11/7
N2 - Feedback by radio-loud active galactic nuclei (AGNs) in galaxy groups is
not fully understood. Open questions include the duty cycle of the AGN,
the spatial extent of the radio lobes, the effect they have on the
intragroup medium and the fate of the cosmic rays. We present the
discovery of a 650 kpc-radio galaxy embedded in steep diffuse emission
at z = (0.18793 ± 5) × 10-5 located at the
centre of the galaxy group MaxBCG J199.31832+51.72503 using an
observation from the LOFAR Two-metre Sky Survey (LoTSS) at the central
frequency of 144 MHz. Subsequently, we performed a Giant Meterwave Radio
Telescope observation at the central frequency of 607 MHz to study the
spectral properties of the source. The observations reveal a radio
galaxy with a total radio power Ptot, 1.4 ˜ 2.1 ×
1024 W Hz-1, exhibiting two asymmetrical jets and
lobes. The derived spectral index map shows a steepening towards the
inner regions and a steep-spectrum core region. We model the integrated
radio spectrum, providing two possible interpretations: the radio source
is evolved but still active or it is just at the end of its active
phase. Finally, in the same field of view we have discovered Mpc-sized
emission surrounding a close pair of AGN located at a redshift z =
(0.0587 ± 2) × 10-4 (SDSS J131544.56+521213.2
and SDSS J131543.99+521055.7) which could be a radio remnant source.
AB - Feedback by radio-loud active galactic nuclei (AGNs) in galaxy groups is
not fully understood. Open questions include the duty cycle of the AGN,
the spatial extent of the radio lobes, the effect they have on the
intragroup medium and the fate of the cosmic rays. We present the
discovery of a 650 kpc-radio galaxy embedded in steep diffuse emission
at z = (0.18793 ± 5) × 10-5 located at the
centre of the galaxy group MaxBCG J199.31832+51.72503 using an
observation from the LOFAR Two-metre Sky Survey (LoTSS) at the central
frequency of 144 MHz. Subsequently, we performed a Giant Meterwave Radio
Telescope observation at the central frequency of 607 MHz to study the
spectral properties of the source. The observations reveal a radio
galaxy with a total radio power Ptot, 1.4 ˜ 2.1 ×
1024 W Hz-1, exhibiting two asymmetrical jets and
lobes. The derived spectral index map shows a steepening towards the
inner regions and a steep-spectrum core region. We model the integrated
radio spectrum, providing two possible interpretations: the radio source
is evolved but still active or it is just at the end of its active
phase. Finally, in the same field of view we have discovered Mpc-sized
emission surrounding a close pair of AGN located at a redshift z =
(0.0587 ± 2) × 10-4 (SDSS J131544.56+521213.2
and SDSS J131543.99+521055.7) which could be a radio remnant source.
KW - galaxies: groups: general
KW - galaxies: jets
KW - galaxies: magnetic fields
KW - radio continuum: galaxies
U2 - 10.1093/mnras/stx2876
DO - 10.1093/mnras/stx2876
M3 - Article
SN - 0035-8711
VL - 474
SP - 5023
EP - 5035
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -