J/MNRAS/496/4654 Radio tails of galaxies in the Coma cluster (Chen+, 2020)
The ram pressure stripped radio tails of galaxies in the Coma cluster.
Chen H., Sun M., Yagi M., Bravo-Alfaro H., Brinks E., Kenney J., Combes F.,
Sivanandam S., Jachym P., Fossati M., Gavazzi G., Boselli A., Nulsen P.,
Sarazin C., Ge C., Yoshida M., Roediger E.
<Mon. Not. R. Astron. Soc., 496, 4654-4673 (2020)>
=2020MNRAS.496.4654C 2020MNRAS.496.4654C (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxies, interacting ; Radio continuum ;
H I data
Keywords: galaxies: clusters: individual: Coma - galaxies: interactions -
galaxies: ISM - radio continuum: galaxies
Abstract:
Previous studies have revealed a population of galaxies in galaxy
clusters with ram pressure stripped (RPS) tails of gas and embedded
young stars. We observed 1.4GHz continuum and HI emission with the
Very Large Array in its B-configuration in two fields of the Coma
cluster to study the radio properties of RPS galaxies. The best
continuum sensitivities in the two fields are 6 and 8uJy per 4arcsec
beam, respectively, which are 4 and 3 times deeper than those
previously published. Radio continuum tails are found in 10 (8 are
new) out of 20 RPS galaxies, unambiguously revealing the presence of
relativistic electrons and magnetic fields in the stripped tails. Our
results also hint that the tail has a steeper spectrum than the
galaxy. The 1.4GHz continuum in the tails is enhanced relative to
their Hα emission by a factor of ∼7 compared to the main bodies
of the RPS galaxies. The 1.4GHz continuum of the RPS galaxies is also
enhanced relative to their infrared emission by a factor of ∼2
compared to star-forming galaxies. The enhancement is likely related
to ram pressure and turbulence in the tail. We furthermore present HI
detections in three RPS galaxies and upper limits for the other RPS
galaxies. The cold gas in D100's stripped tail is dominated by
molecular gas, which is likely a consequence of the high ambient
pressure. No evidence of radio emission associated with ultra-diffuse
galaxies is found in our data.
Description:
To further study Coma galaxies at radio frequencies, we obtained
1.4GHz continuum and HI data with the NRAO Karl G. Jansky Very Large
Array (VLA) in its B-configuration in two fields centred at NGC4848
and D100, respectively, from 2016 June 1st to 11th (see Table 1,
program code: SH0174, PI: Sun). The 1.4GHz continuum data were taken
with two base bands (A0/C0 and B0/D0) covering a frequency range from
0.9 to 2.1GHz; each base band is constructed with seven spectral
windows of 128MHz, and each spectral window is divided into 64
channels of 2MHz. The HI spectral data were taken with two spectral
windows (one for A0/C0 and the other for B0/D0) of 64MHz covering a
velocity range of 1000-11200km/s. Each spectral window is divided into
3584 channels of 17.8kHz (or 3.88km/s velocity resolution).
Objects:
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RA (ICRS) DE Designation(s)
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12 59 48.69 +27 58 49.9 ACO 1656 = 1ES 1257+28.2 = NAME Coma Cluster
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 41 3148 The full continuum source catalogue
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID [1/3148] Internal source identifier
6- 7 I2 h RAh Right ascension (J2000) (1)
9- 10 I2 min RAm Right ascension (J2000) (1)
12- 16 F5.2 s RAs [] Right ascension (J2000) (1)
18 A1 --- DE- Declination sign (J2000) (1)
19- 20 I2 deg DEd Declination (J2000) (1)
22- 23 I2 arcmin DEm Declination (J2000) (1)
25- 28 F4.1 arcsec DEs [] Declination (J2000) (1)
30- 35 I6 uJy Sint Integral flux density at 1.4GHz
37- 39 I3 uJy e_Sint Error on Sint
41 I1 --- field [1/2] Field in which the source was found (2)
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Note (1): Coordinates of radio source peak
Note (2): Field as follows:
1 = source was found in field 1 (shown in Figure 1 of the article)
2 = source was found in field 2 (shown in Figure 1 of the article)
For the 64 sources covered by both fields, their results from the two
fields are listed in different rows, respectively, and the same source
ID was set for the same source
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 20-Jul-2023