J/A+A/695/A178 Radio AGN jet paths and their cluster weather (Vardoulaki+, 2025)
The jet paths of radio AGN and their cluster weather.
Vardoulaki E., Backoefer V., Finoguenov A., Vazza F., Comparat J.,
Gozaliasl G., Whittam I.H., Hale C.L., Weaver J.R., Koekemoer A.M.,
Collier J.D., Frank B., Heywood I., Sekhar S., Taylor A.R., Pinjarkar S.,
Hardcastle M.J., Shimwell T., Hoeft M., White S.V., An F., Tabatabaei F.,
Randriamanakoto Z., Filipovic M.D.
<Astron. Astrophys. 695, A178 (2025)>
=2025A&A...695A.178V 2025A&A...695A.178V (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Clusters, galaxy ; Radio sources ;
Redshifts
Keywords: galaxies: abundances - galaxies: active -
galaxies: clusters: intracluster medium - galaxies: groups: general -
galaxies: jets
Abstract:
We studied bent radio sources within X-ray galaxy groups in the COSMOS
and XMM-LSS fields. The radio data were obtained from the MeerKAT
International GHz Tiered Extragalactic Explorations data release 1
(MIGHTEE-DR1) at 1.2-1.3GHz, with angular resolutions of 8.9" and 5",
and median noise levels rmsmed~=3.5 and 5.5uJy/beam. Bent radio
active galactic nuclei (AGN) were identified through visual
inspection. Our analysis included 19 bent radio AGN in the COSMOS
field and 17 in the XMM-LSS field which lie within X-ray galaxy groups
(2x1013≲M200c/M☉≤3x1014). We investigated the relationship
between their bending angle (BA) - the angle formed by the jets or
lobes of two-sided radio sources associated with AGN - and the
properties of their host galaxies and large-scale environment probed
by the X-ray galaxy groups. Our key findings are: a) In the XMM-LSS
field, we observed a strong correlation between the linear projected
size of the bent AGN, the group halo mass, and the projected distance
from the group centre. This trend, consistent with previous studies,
was not detected in the COSMOS sample. b) The BA is a function of
environmental density, with the type of medium playing a significant
role. Additionally, at z≤0.5 we found a higher number of bent sources
(BA≤160°) compared to higher redshifts (z∼1), by a factor of
>1.5. This trend aligns with magnetohydrodynamic simulations, which
suggest that denser environments and longer interaction times at lower
redshifts contribute to this effect. Comparison with the literature
suggests that jet bending in galaxy groups within the redshift range
0.1<z<1.2 is primarily driven by ram pressure exerted on the jets,
which occurs during quiescent phases of AGN activity. This study
underscores the role of environmental interactions in shaping the
morphology of radio AGN within galaxy groups, providing insights into
the interplay between large-scale structure and AGN physics.
Description:
In this work, we investigated the bent radio sources located in the
COSMOS and XMM-LSS fields, selected from visual inspection of the
MIGHTEE-DR1 radio survey at ∼1.2-1.3GHz with beam sizes of 8.9" and
∼5", and median central rms of ∼3.2-3.5uJy/beam and ∼5.1-5.6uJy/beam,
respectively. We found 217 objects in XMM-LSS and 142 objects in
COSMOS where we could robustly measure the bending angle, i.e. the
angle formed between the jets/lobes of a two-sided source.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tableb1.dat 128 17 Properties of bent AGN in XMM-LSS within
X-ray galaxy groups
tableb2.dat 132 19 Properties of bent AGN in COSMOS within
X-ray galaxy groups
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tableb1.dat tableb2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- ObjectID The 1.28GHz radio ID assigned to the source
(ObjectID)
5- 13 F9.5 deg RAdeg Right Ascension (J2000.0) radio position
(Radio_RA(deg.J2000))
15- 22 F8.5 deg DEdeg Declination (J2000.0) radio position
(Radio_DEC(deg.J2000))
24- 32 F9.5 deg RAHdeg Right Ascension (J2000.0) host position
(Host_RA(deg.J2000))
34- 41 F8.5 deg DEHdeg Declination (J2000.0) host position
(Host_DEC(deg.J2000))
43- 47 F5.3 --- z Redshift of the radio source (Redshift)
49 A1 --- f_z [PS] Redshift flag: S for spectroscopic,
P for photometric (redshift_flag)
51- 55 F5.3 --- b_z ?=- The lower bounds of the redshift
at 68% confidence level (z_l68)
57- 61 F5.3 --- B_z ?=- The upper bounds of the redshift
at 68% confidence level (z_u68)
63- 74 A12 --- r_z The survey from which the redshift value
is obtained (z_ref)
76- 78 I3 arcsec LAS The largest angular size (LAS) of the radio
source (LAS_("))
80- 83 I4 kpc Size The projected linear size of the radio
source, calculated from the largest angular
size and the redshift (Size_(kpc))
85- 87 I3 deg BAflux ?=- The bending angle, measured from the peak
flux positions of the jets/lobes
(BendingAngleBA_flux(deg.))
89- 91 I3 deg BAedge The bending angle, measured from the edges of
the jets/lobes (BendingAngleBA_edge(deg.))
93- 99 F7.3 mJy FluxDens Flux density at ∼1.2-1.3GHz of the radio
source (FluxdensitymJy)
101-105 F5.2 [W/Hz] logL1.4GHz Radio Luminosity at 1.4GHz, calculated using
the median frequency at 1.28GHz and a
typical radio spectral index of alpha=0.7
(log10(L1.4GHz/W/Hz))
107-132 A26 --- Tags Tags that describe the radio morphology
(Tags) (1)
--------------------------------------------------------------------------------
Note (1): The assigned tags are chosen from jets/no-jets, one-sided,
bent/not-bent, X/S/Z-shaped, WAT, NAT, blended, peculiar and
giant radio galaxy (GRG), for sources that are at or greater than 1Mpc in
linear size.
A '?' is added to the tag if the assessment of the tag is deemed uncertain.
--------------------------------------------------------------------------------
Acknowledgements:
Eleni Vardoulaki, elenivard(at)gmail.com
(End) Patricia Vannier [CDS] 10-Feb-2025