J/ApJ/934/170 Deep uGMRT 250-850MHz view of Coma cluster galaxies (Lal+, 2022)
High-resolution, high-sensitivity, low-frequency uGMRT view of Coma cluster of
galaxies.
Lal D.V., Lyskova N., Zhang C., Venturi T., Forman W.R., Jones C.,
Churazov E.M., van Weeren R.J., Bonafede A., Miller N.A., Roberts I.D.,
Bykov A.M., Di Mascolo L., Bruggen M., Brunetti G.
<Astrophys. J., 934, 170 (2022)>
=2022ApJ...934..170L 2022ApJ...934..170L
ADC_Keywords: Clusters, galaxy; Galaxies, radio; Redshifts; Morphology;
Spectra, radio
Keywords: Coma Cluster ; Astrophysical black holes ; Galaxy clusters ;
High energy astrophysics ; Intracluster medium ;
Radio continuum emission ; Radio galaxies ; Supermassive black holes ;
Tailed radio galaxies ; X-ray active galactic nuclei
Abstract:
We present high-resolution, high-sensitivity upgraded Giant Metrewave
Radio Telescope observations of the Coma cluster (A1656) at 250-500MHz
and 550-850MHz. At 250-500MHz, 135 sources have extensions >0.45'
(with peak-to-local-noise ratio >4). Of these, 24 sources are
associated with Coma-member galaxies. In addition, we supplement this
sample of 24 galaxies with 20 ram pressure stripped (RPS) galaxies
from (Chen+ 2020, J/MNRAS/496/4654), eight are included in the
original extended radio source sample) and an additional five are
detected and extended. We present radio morphologies, radio spectra,
spectral index maps, and equipartition properties for these two
samples. In general, we find the equipartition properties lie within a
narrow range (e.g., Pmin=1-3x10-13dynes/cm2). Only NGC 4874, one
of the two brightest central Coma cluster galaxies, has a central
energy density and pressure about five times higher and a radio source
age about 50% lower than that of the other Coma galaxies. We find a
diffuse tail of radio emission trailing the dominant galaxy of the
merging NGC 4839 group that coincides with the slingshot tail seen in
X-rays. The southwestern radio relic, B1253+275, has a large extent
∼32'x10' (∼1.08x0.34Mpc2). For NGC 4789, whose long radio tails
merge into the relic and may be a source of its relativistic seed
electrons, we find a transverse radio spectral gradient, a steepening
from southwest to northeast across the width of the radio source.
Finally, radio morphologies of the extended and RPS samples suggest
that these galaxies are on their first infall into Coma on
(predominantly) radial orbits.
Description:
The Giant Metrewave Radio (GMRT) has been upgraded with a completely
new set of receivers at frequencies <1.5GHz. The upgraded Giant
Metrewave Radio Telescope (uGMRT) has (nearly) seamless frequency
coverage in the 0.050-1.50GHz range. The data reported here include
archival data (Obs_IDs: DDT-ddtb270 and 35_005) and new observations
(Obs_ID 36_033) spanning 2017-04-28 to 2019-06-14. Our observations
are made in the frequency bands 250-500MHz and 550-850MHz at angular
resolutions of ∼6.1" and ∼3.7", respectively, and cover approximately
∼7.5deg2 around the Coma cluster region.
The Coma cluster has been observed multiple times with Chandra and
XMM-Newton. To investigate the interaction of the radio lobes of one
of two core bright cluster galaxies (BCGs), NGC 4874 with its
environment, we used Chandra observations (Obs_IDs 13993 13994, 13995,
13996, 14406, 14410, 14411, and 14415). See Section 2.2.
We culled a complete sample of 24 radio sources that are associated
with the Coma cluster galaxies, whose radial velocities are in the
range of 4000-9400km/s. We also supplement this radio-selected sample
with 20 ram pressure stripped (RPS) galaxies from
(Chen+ 2020, J/MNRAS/496/4654), of which eight are included in the
extended radio source sample and an additional five are detected and
extended.
Throughout this paper, we adopt a Λ cold dark matter cosmology
with H0=70km/s/Mpc, Ωm=0.27, and ΩΛ=0.73. At
the mean redshift of the Coma cluster, z=0.02316, 1" corresponds to
467pc at the luminosity distance of 100.7Mpc.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
12 59 44.4 +27 54 45 Coma cluster = ACO 1656
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 111 24 Radio properties of the 24 extended (≳12.6kpc) Coma
cluster-member sources detected using the uGMRT
table4.dat 115 20 Radio properties of the ram pressure stripped (RPS)
galaxies in the Coma cluster field observed
using the uGMRT
tablea1.dat 109 111 Summary of the nature of radio sources in the
Coma cluster field using the uGMRT
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
B/xmm : XMM-Newton Obs. Log (XMM-Newton Science Operation Center, 2012-)
VII/4 : Abell and Zwicky Clusters of Galaxies (Abell+ 1974)
VII/110 : Rich Clusters of Galaxies (Abell+ 1989)
J/A+AS/105/385 : Radio observations of Coma cluster I (Kim+ 1994)
J/MNRAS/305/259 : EFAR gal. redshifts & velocity dispersions (Wegner+, 1999)
J/AJ/124/2453 : Sp. of active galaxies in nearby clusters (Miller+, 2002)
J/AJ/137/4436 : Coma cluster VLA survey (Miller+, 2009)
J/ApJ/740/59 : 1.4GHz & X-ray sources in 12 clusters of gal. (Hart+, 2011)
J/ApJS/230/7 : Spectral flux densities from 50MHz to 50GHz (Perley+, 2017)
J/MNRAS/496/4654 : Radio tails of galaxies in the Coma cluster (Chen+, 2020)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/24] Running sequence number
4- 26 A23 --- Name Name of the source as in NED
28 A1 --- f_Name Flag on Name (1)
30- 31 I2 h RAh Hour of right ascension (J2000) (2)
33- 34 I2 min RAm Minute of right ascension (J2000)
36- 40 F5.2 s RAs Second of right ascension (J2000)
42 A1 --- DE- Sign of declination (J2000) (2)
43- 44 I2 deg DEd Degree of declination (J2000) (2)
46- 47 I2 arcmin DEm Arcminute of declination (J2000)
49- 52 F4.1 arcsec DEs Arcsecond of declination (J2000)
54- 60 F7.5 --- z [0.016/0.04] Spectroscopic redshift
62- 64 I3 uJy/beam rmsB3 [12/384] Local RMS noise in the near vicinity
of source for 250-500MHz (band 3)
66- 67 I2 uJy/beam rmsB4 [12/96]? Local RMS noise in the near vicinity
of source for 550-850MHz (band 4)
69- 74 F6.1 mJy S400MHz [3.3/1381] 250-500MHz (band 3) flux density (G2)
76- 78 F3.1 mJy e_S400MHz [0.1/10] S400MHz uncertainty
80- 84 F5.1 mJy S700MHz [1.7/736]? 550-850MHz (band 4) flux density (G2)
86- 88 F3.1 mJy e_S700MHz [0.1/2.4]? S700MHz uncertainty
90- 94 F5.2 --- alpha [-1.3/0.11]? 250-500MHz (band 3) and
550-850MHz (band 4) spectral index (4)
96- 99 F4.2 --- e_alpha [0.01/0.14]? alpha uncertainty
101- 111 A11 --- Morph Radio source morphology classification (G1)
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Note (1): Flag as follows:
a = RPS galaxies (see also Table 4 and Section 4.2).
b = Sources not covered in our 550-850MHz band pointings.
Note (2): The R.A. and decl. (J2000) of the optical host associated with the
probable radio core.
Note (4): The spectral index at 250-500MHz (band 3) and 550-850MHz (band 4) at
angular resolutions of ∼6.1" and ∼3.7", respectively (see also the
discussion in Section 4.1.1).
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- Seq Running letter index
3- 15 A13 --- Name Name as in NED
17 A1 --- f_Name Flag on Name (1)
19- 20 I2 h RAh Optical host hour of right ascension (J2000)
22- 23 I2 min RAm Minute of right ascension (J2000)
25- 29 F5.2 s RAs Second of right ascension (J2000)
31 A1 --- DE- Optical host sign of declination (J2000)
32- 33 I2 deg DEd Optical host degree of declination (J2000)
35- 36 I2 arcmin DEm Arcminute of declination (J2000)
38- 41 F4.1 arcsec DEs Arcsecond of declination (J2000)
43- 46 I4 km/s Vel [4565/9416] Optical velocity from
Chen+ (2020, J/MNRAS/496/4654)
48- 49 I2 uJy/beam rmsB3 [12/36] Local rms noise in the near
vicinity of the source for 250-500MHz
(band 3)
51- 52 I2 uJy/beam rmsB4 [12/24]? Local rms noise in the near
vicinity of the source for 550-850MHz
(band 4)
54- 55 A2 --- l_S400MHz [~< ] Limit flag on S400MHz (2)
57- 61 F5.2 mJy S400MHz [0.19/60.66] Flux density of the RPS galaxy
at 250-500MHz (band 3) (G2)
63- 66 F4.2 mJy e_S400MHz [0.21/2.12]? S400MHz uncertainty
68- 69 A2 --- l_S700MHz [~< ] Limit flag on S700MHz (2)
71- 75 F5.2 mJy S700MHz [0.11/43.41] Flux density of the RPS galaxy
at 550-850MHz (band 4) (G2)
77- 80 F4.2 mJy e_S700MHz [0.12/0.8]? S700MHz uncertainty
82 A1 --- f_S700MHz Flag on S700MHz (1)
84- 85 A2 --- l_alpha [~< ] Limit flag on alpha
87- 91 F5.2 --- alpha [-2.05/-0.45]? Spectral index at 250-500MHz
(band 3) and 550-850MHz (band 4) of the
source
93- 96 F4.2 --- e_alpha [0.04/0.46]? alpha uncertainty
98 A1 --- l_S1.4GHz Limit flag on S1.4GHz
100- 105 F6.3 mJy S1.4GHz [0.03/23.85] The flux densities of the RPS
galaxy at 1.4GHz taken from Chen+
(2020, J/MNRAS/496/4654)
107- 110 F4.2 mJy e_S1.4GHz [0.01/0.23]? S1.4GHz uncertainty
112- 115 A4 --- Morph Radio source morphology classification (G1)
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Note (1): Flag as follows:
a = Extended radio source (see Table 3 and Section 4.2 for a discussion).
b = Sources not covered in our 550-850MHz band pointings.
G = measurements (upper limits) are from the nearest locations covered in
our 250-500MHz band pointings.
Note (2): An upper limit of five times the local rms is quoted for
non-detected RPS galaxies.
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [1/111] Running sequence number
5- 29 A25 --- Name NED identifier if any
31- 32 I2 h RAh Radio core (400MHz) hour of right ascension
(J2000)
34- 35 I2 min RAm Radio core (400MHz) minute of right ascension
(J2000)
37- 41 F5.2 s RAs Radio core (400MHz) second of right ascension
(J2000)
43 A1 --- DE- Radio core (400MHz) sign of declination
(J2000)
44- 45 I2 deg DEd Radio core (400MHz) degree of declination
(J2000)
47- 48 I2 arcmin DEm Radio core (400MHz) arcminute of declination
(J2000)
50- 53 F4.1 arcsec DEs Radio core (400MHz) arcsecond of declination
(J2000)
55- 61 F7.5 --- z [7e-05/2.3]? Spectroscopic redshift
as reported in NED
63 A1 --- n_z p=photometric redshift
65- 67 I3 uJy/beam rmsB3 [12/768] Local RMS noise in the near vicinity
of source for 250-500MHz (band 3)
69- 71 I3 uJy/beam rmsB4 [12/384]? Local RMS noise in the near vicinity
of source for 550-850MHz (band 4)
73- 81 A9 --- Morph Radio source morphology classification (G1)
83-105 A23 --- OName Alternate name(s) as reported in NED
107-109 A3 --- f_OName M09 = Alternate name from
Miller et al. 2009, J/AJ/137/4436
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Global notes:
Note (G1): The radio source morphology classification following
Rudnick (2021Galax...9...85R 2021Galax...9...85R). Code as follows:
A = amorphous;
BT = bend tail;
CD = classical double;
cD = compact dominant;
D = diffuse;
FR II = FR type II source;
HT = head tail;
NAT = narrow-angle tailed;
T = tailed source;
Tr = Triple;
W = winged (or X-shaped);
WAT = wide-angle tail;
Z = Z symmetric.
Note (G2): The flux densities of the RPS galaxies at 250-500 MHz (band 3) and
550-850MHz (band 4) at angular resolutions of ∼6.1" and ∼3.7", respectively.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 26-Jul-2024